title: Relationship between growth of cultured mussels (Mytilus edulis) and food availability in Tracadie Bay, Prince Edward Island

contributor: Johnson, Gerry (Supervisory Committee Member)

contributor: Grant, Jon (Supervisory Committee Member)

contributor: Landry, Thomas (Supervisory Committee Member)

format: 113 electronic application/pdf

subject:
Biology, Ecology
Agriculture, Fisheries and Aquaculture

abstract: The purpose of this study was to (1) describe the growth of blue mussels (Mytilus edulis) in an intensively cultured embayment, (2) document the temporal and spatial variations in the composition of suspended particulate matter, and (3) assess the temporal and spatial variations in food quantity and quality associated with variations in mussel growth. The study relates seston depletion and resulting mussel growth in a commercial culture setting at a bay-level scale. Caged mussels (age 1 cohorts) were maintained at 5 experimental sites in Tracadie Bay (Prince Edward Island, Canada), during May through October 1998 and 1999, to monitor seasonal growth (shell length and meat weight). Water samples for analyses of seston parameters (as indicators of food quantity and nutritional quality) were collected concurrent with mussel sampling. Coefficients of individual second-order polynomial regressions were used to document seasonal, annual and spatial variations in mussel growth. (Abstract shortened by UMI.).

abstract: Source: Masters Abstracts International, Volume: 43-02, page: 0489.

abstract: Adviser:  Jeff Davidson.


title: Relationship between student attitudes toward physical education and student leisure time physical activity levels

type: Text Dissertation/Thesis

contributor: Vokey, Daniel (Supervisory Committee Member)

format: 91 electronic application/pdf

subject:
Education, Physical
Recreation

abstract: This study was designed to study the relationship between student attitudes toward physical education and student leisure time physical activity levels. The Physical Education Survey was used to measure students' attitudes towards physical education. This questionnaire evaluates overall attitudes, as well as attitudes for three sub-scales: lack of meaning, powerlessness, and feeling of isolation. The Past Year Leisure Time Physical Activity Survey was used to assess student activity levels. This questionnaire asked students to indicate the type and duration of physical activities in which they participated over the past year. The data derived from this questionnaire was then converted to hours per week of physical activity and MET hours per day. This is a measurement of the amount of energy the body uses to complete an activity. MET values for specific activities can be obtained from existing tables.

abstract: The population consisted of grade seven students from the Eastern School District on Prince Edward Island. Random Cluster Sampling was used to select 15 classes from a total of 59 classes (25%). A return rate of 75% (n = 261) was achieved. (Abstract shortened by UMI.).

abstract: Source: Masters Abstracts International, Volume: 40-04, page: 0837.

abstract: Adviser: Xiufeng Liu.


title: Immunologic monitoring and treatment of gastrointestinal parasites in dairy cattle

contributor: Spangler, Liz (Supervisory Committee Member)

contributor: Barkema, Herman (Supervisory Committee Member)

contributor: Leslie, Ken (Supervisory Committee Member)

contributor: Markam, Fred (Supervisory Committee Member)

contributor: Keefe, Greg (Supervisory Committee Member)

format: 210 electronic application/pdf

subject:
Agriculture, Animal Pathology
Biology, Veterinary Science

abstract: Gastrointestinal (GIT) nematodes have been shown to have a detrimental effect on milk production and reproduction in adult dairy cows. Fecal egg counts (FEC) have been shown to be unreliable measures of worm burden in adult cows. An indirect crude adult worn Ostertagia ostertagi enzyme-linked immunosorbent assay (ELISA) has shown promise in its ability to measure worm burden. ELISA optical density ratio (ODR) values are associated with milk production and pasture exposure in a predictable way. Eprinomecin treatment of adult dairy cows at is associated with increased in milk production in pastured herds. The ELISA has a lot of promise in its ability to predict a milk production or reproduction response to anthelmintic treatment. The ELISA could be used as a herd health management tool to predict cows/herds that will benefit from deworming. The main goals of this study were (1) to establish the benefit of deworming cows with eprinomectin at calving on milk production and reproduction in 64 dairy herds with limited outdoor exposure in the summer, (2) to evaluate the ability of a bulk milk ELISA in identifying dairy herds whose milk production and reproduction would benefit from eprinomectin treatment, (3) to evaluate the accuracy of DHI reproduction records, (4) to evaluate the association between GIT nematodes and energy status of cows at calving, and (5) to further develop the ELISA by evaluating a selection of blocking agents, conjugates and antigens.

abstract: Eprinomectin treatment did not improve milk production and reproduction in herds with limited pasture exposure. However, it did provide some evidence that the ELISA may be more effective than FEC at identifying herds in which a positive treatment effect might be expected.

abstract: Because earlier studies found a significant treatment effect in cows that were dewormed around calving, a study to establish the impact of deworming on the peripartum energy status, was conducted. Parasite burden in the previous lactation, had a negative impact on the energy status of the cows, at ODR values greater than 0.4. However, the lack of an anthelmintic treatment effect may have been due to the low parasite burdens in the study herds.

abstract: The stability of ELISA plates prepared with one of 3 blocking agents and used with one of 2 conjugates (monoclonal and polyclonal) at various time intervals after preparation of the plates, was assessed. ODR values of all the blocking agent/conjugate combinations were consistent over a year. Two of the blocking agents enabled plates to be stored dry, at room temperature, making them convenient to use and transport. ELISA results suggested that the larval stage 4 and adult excretory/secretory antigens elicit a stronger humoral immune response than the crude adult antigen. Further studies to compare the abilities of the antigens in identifying cows/herds that would benefit from anthelmintic treatment need to be conducted. (Abstract shortened by UMI.).

abstract: Source: Dissertation Abstracts International, Volume: 66-12, Section: B, page: 6473.


title: Importance of detritus, substrate and flow to macroinvertebrate distribution in sections of the West River

contributor: Peters, Wayne (Supervisory Committee Member)

contributor: Guignion, Daryl (Supervisory Committee Member)

format: 207 electronic application/pdf

subject: Biology, Limnology

abstract: The importance of near-bed flow and other types of environmental variables to macroinvertebrate distribution was examined within sections of a stream in Prince Edward Island. To carry out this part of the study, different methods of measuring near-bed flow were tested. The methods were tested at 5 sites on 3 streams, to choose the most practical and reliable methods for evaluating shear velocity and roughness to compare near-bed flow among patches where macroinvertebrates were later sampled. Therefore, results from the standard, but very time-consuming, method of measuring shear velocity using velocity profiles were compared to results obtained using alternative methods. The alternative methods tested included the use of FST hemispheres, and the prediction of shear velocity from more easily measured hydraulic variables (near-bed velocity, mean velocity, depth and roughness).

abstract: Macroinvertebrates were sampled in August and November of 2001 in patches set in a regular arrangement at two sites, a “run site” and a nearby small “riffle site”. The densities of macroinvertebrate taxa at the run site were compared to patch substrate size composition, algal cover, different size fractions of detritus and various hydraulic variables. (Abstract shortened by UMI.).

abstract: Source: Masters Abstracts International, Volume: 43-02, page: 0491.

abstract: Adviser:  Donna Giberson.


title: Importance of eelgrass (Zostera marina) to fishes in North Shore estuaries on Prince Edward Island

contributor: van den Heuvel, Mike (Supervisory Committee Member)

contributor: Courtenay, Simon (Supervisory Committee Member)

format: 212 electronic application/pdf

subject:
Biology, Ecology
Environmental Sciences
Agriculture, Fisheries and Aquaculture

abstract: Seagrass beds are known to support an abundant and diverse ichthyofauna and are generally considered essential habitats within estuarine and coastal environments. On Prince Edward Island (PEI) anthropogenic activities within watersheds are causing eutrophication of estuaries resulting in macroalgal (primarily sea lettuce, Ulva lactuca) proliferation and degradation and loss of eelgrass (Zostera marina) habitat. This project aimed to: 1) examine the impacts of sea lettuce on eelgrass and the eelgrass fish community using 1 m2 enclosures and a 12 m2 exclosure respectively; 2) investigate diel and seasonal patterns of eelgrass habitat use to increase our understanding of eelgrass habitat importance to a variety of estuarine fish species; 3) determine how the fish community composition varies with eelgrass habitat condition; and, 4) explore the effects of eelgrass habitat loss on an eelgrass dependant species, northern pipefish ( Syngnathus fuscus).

abstract: To examine how sea lettuce was affecting eelgrass, 1 m2 experimental enclosures were constructed to measure changes in eelgrass density and above-ground biomass in response to sea lettuce canopy cover. To explore how the eelgrass fish community was being impacted by sea lettuce, bi-weekly beach seines were conducted at three sites in the Midgell River estuary from July 20th to September 12th, 2009. One site was sea lettuce habitat, the second was mixed eelgrass and sea lettuce, and the third site was an exclosure in which sea lettuce was removed from an eelgrass bed. Treatments containing macroalgal canopies were found to significantly reduce the measured characteristics (shoot density, blade density, leaf area, and above-ground biomass) of eelgrass. The exclosure was effective at maintaining a monospecific eelgrass habitat. Fish communities did not differ significantly among the three sites, although fourspine stickleback (Apeltes quadracus ) were captured in higher numbers in the eelgrass habitat.

abstract: Beach seines were conducted at over 24 h periods twice monthly from June to August 2008 in the Midgell River estuary to better understand the dynamics of eelgrass habitat use within the estuarine environment. Fish were sampled by carrying out two seines, separated by no more than 5 m every four hours. Significantly more individuals occurred in eelgrass habitats throughout the night (22:00-4:00 h) than during the day (6:00-20:00 h). Atlantic silverside (Menidia menidia) young-of-the-year (YOY), mummichog (Fundulus heteroclitus), and American eel (Anguilla rostrata) were captured significantly more often at night, while ninespine stickleback ( Pungitius pungitius) were captured more frequently during the day. Diel variation differed between months; however, within a given month day catches were generally dominated by Gasterosteus spp. YOY, ninespine stickleback, threespine stickleback (G. aculeatus), and northern pipefish YOY. Night catches generally had higher numbers of mummichog and Atlantic silverside YOY.

abstract: Ten sites in each of eight different estuaries along the north shore of PEI were chosen to examine the relationship between fish community structure and the condition of the eelgrass habitat, based on shoot density, canopy height, percent cover, above-ground biomass, and epiphyte biomass. Fish were sampled by beach seining ten sites in each estuary in June and August 2009. Measures of eelgrass were recorded at the same time as seining occurred using a 0.5 m2 viewing frame and core sampler. Generally, eelgrass complexity did not affect the adult community in June or August as they responded differences in water parameters (temperature, salinity, dissolved oxygen). In contrast, young-of-the-year (YOY) fishes responded to both water parameters and increased eelgrass complexity. For example, young-of-the-year northern pipefish, winter flounder, Gasterosteus spp., and cunner were sampled in higher numbers in areas of higher shoot density.

abstract: Northern pipefish, an eelgrass dependent species, were used to assess potential impacts of continued eelgrass habitat degradation. Pipefish were sampled every ten days from May to October, 2009 in an eelgrass and sea lettuce dominated habitat within the Stanley River estuary. Five consecutive seines in each habitat type were conducted to assess population differences. Males, females, and YOY were all significantly more abundant in the eelgrass habitat than in the sea lettuce. Male S. fuscus showed no significant difference in brood pouch somatic index (BPSI) between the sea lettuce and eelgrass habitats. Although, brood sizes of males sampled from sea lettuce were significantly smaller than eelgrass males, this was related to their smaller size. Gonadosomatic index (GSI) of females did not differ between the sea lettuce and eelgrass habitats.

abstract: Generally, the overall capacity of estuarine environments to support a diverse and abundant fish community is being affected by structural changes in the eelgrass habitat. Taken together, these results provide further evidence that eelgrass beds are an important habitat for estuarine fish species.

abstract: Source: Masters Abstracts International, Volume: 50-04, page: 2249.


title: In vitro efficacy of six antibiotics and plasma concentrations of two quinolones in Atlantic salmon (Salmo salar)

contributor: Rainnie, D.J. (Supervisory Committee Member)

contributor: Markham, R.J. Frederick (Supervisory Committee Member)

contributor: Novotny, M. (Supervisory Committee Member)

contributor: Long, J.R. (Supervisory Committee Member)

format: 187 electronic application/pdf

subject:
Agriculture, Animal Pathology
Biology, Veterinary Science
Agriculture, Fisheries and Aquaculture

abstract: The minimum inhibitory concentrations (MICs) of six antibiotics were determined for Aeromonas salmonicida, Vibrio anguillarum and Vibrio ordalii isolated from disease outbreaks in fish on the Atlantic and Pacific coasts. MICs were performed at three incubation temperatures (10, 20, 30$\sp\circ$C). Incubation temperature influenced the MIC for some antibiotics. The most pronounced case was a two-fold or greater increase in the MIC of oxytetracycline against Vibrio spp. with increasing temperature. Changes in resistance patterns were examined in the isolates collected from 1985 to 1990. The in vitro efficacy of the antibiotics examined ranged from the potent quinolones (oxolinic acid and sarafloxacin) to ormetoprim-sulfadimethoxine and oxytetracycline, to the relatively ineffective drugs erythromycin and streptomycin.

abstract: The plasmid profiles of oxytetracycline and streptomycin resistant and sensitive bacterial isolates were examined by agarose gel electrophoresis. Resistant isolates were examined when grown in the presence and in the absence of antibiotic. Resistance to these antibiotics did not appear to be plasmid-mediated. (Abstract shortened by UMI.).

abstract: Source: Masters Abstracts International, Volume: 31-04, page: 1628.


title: In vitro investigation of the fluoroquinolone-theophylline drug interaction in dogs

contributor: Tasker, Andrew (Supervisory Committee Member)

contributor: Lemke, Kip (Supervisory Committee Member)

format: 114 electronic application/pdf

subject: Health Sciences, Pharmacology

abstract: Theophylline is a drug with a low therapeutic index and is mainly cleared by hepatic metabolism. The concurrent treatment of humans with the bronchodilator theophylline and certain fluoroquinolone antibiotics, such as ciprofloxacin, can lead to clinical signs of theophylline toxicity. The mechanism for this drug interaction is inhibition of hepatic cytochrome P450 (CYP)-dependent theophylline metabolism by the fluoroquinolones. Enrofloxacin has been shown to inhibit theophylline clearance in Beagle dogs, and marbofloxacin may share similar properties. Therefore, we investigated the ability of enrofloxacin, ciprofloxacin (the major metabolite of enrofloxacin in dogs in vivo ) and marbofloxacin to inhibit nicotinamide adenine dinucleotide phosphate (NADPH)-dependent theophylline metabolism by canine hepatic microsomes in vitro. Theophylline was incubated with canine hepatic microsomes and NADPH in the presence and absence of 50 μg/mL enrofloxacin, ciprofloxacin, or marbofloxacin. (Abstract shortened by UMI.).

abstract: Source: Masters Abstracts International, Volume: 44-03, page: 1344.


title: In vitro stability of natural and synthetic proteins for potential application in animal feeding

contributor: Kibenge, Frederick (Supervisory Committee Member)

contributor: McNiven, Mary A. (Supervisory Committee Member)

contributor: Ogilvie, Tim (Supervisory Committee Member)

contributor: Pringle, J.D. (Supervisory Committee Member)

format: 100 electronic application/pdf

subject: Agriculture, Animal Culture and Nutrition

abstract: Milk Bundle-1 is a de novo designed protein with 100 amino acids, having a molecular weight of 11.4 kilodaltons. MB-1 is enriched with 57% of selected essential amino acids (methionine, threonine, lysine and leucine) and is intended as a feed additive for dairy cows. In order to predict the behaviour of MB-1 in rumen environment, in vitro experiments were conducted to investigate its structural as well as its proteolytic stability.

abstract: Optimization of fluorescence technique was conducted by studying the structural stability of jack bean urease. The results indicated the hexameric urease structure dissociates into folded dimers which then aggregate or dissociate into unfolded monomers.

abstract: Fluorescence spectroscopy was used to study the thermal stability of MB-1. Denaturation studies of MB-1 were conducted in the presence of physiological levels of volatile fatty acids in a buffer with ionic strength and pH similar to rumen fluid. Under these conditions, the melting temperature was obtained to be around 50$\sp\circ$C. This suggested that MB-1 will have a folded structure at the nrmen temperature of 39$\sp\circ$C. This feature is important in that it indicates that MB-1's structure and folding will contribute to a higher resistance to in vivo degradation.

abstract: Proteolytic stability was investigated using two proteases of microbial origin. Pronase E (from Strepromyces griseus) and Neutrase (from Bacillus subtilis) were used according to a procedure currently used as a standard methodology in feed evaluation laboratories. The results of these studies revealed that MB-1 is more degradable than cytochrome c, ribonuclease A and urease. (Abstract shortened by UMI.).

abstract: Source: Masters Abstracts International, Volume: 34-05, page: 1833.

abstract: Adviser: Marc Beauregard.


title: In vitro studies of eosinophilic granule cells of rainbow trout (Oncorhynchus mykiss) small intestine

contributor: Speare, David (Supervisory Committee Member)

contributor: Wright, Glenda (Supervisory Committee Member)

format: 93 electronic application/pdf

subject:
Biology, Cell
Biology, Animal Physiology

abstract: In this study, an attempt was made to induce the degranulation of Eosinophilic granule cells (EGCs) from rainbow trout (Oncorhynchus mykiss) small intestine in vitro using the mast cell secretagogues compound 48/80 (100 $\mu$g/ml) and A23187 (10 $\mu$g/ml). Evaluation of EGC degranulation was done at both a histological and biochemical level.

abstract: Cell counting at the light microscope level was used to determine if exposure to compound 48/80 or A23187 would result in a significant decrease in the number of intact EGCs in the stratum compactum of the trout intestine. Tissues (n = 4) were exposed for 30 minutes to one of the above agents or its respective control. Evidence of a significant decrease in the number of intact EGCs in the treatment tissues was not observed (p $>$ 0.05). This was due in part to regions of explosive degranulation evident in both control and treatment tissues. This nonspecific degranulation may have masked any observable effects of in vitro exposure to compound 48/80 or A23187.

abstract: High performance liquid chromatography (HPLC) was used to determine if exposure to either compound 48/80 or A23187 could result in the release of the mast cell mediator serotonin. Tissue bath concentrations of serotonin were measured before and 30 minutes after exposure to both drugs (n = 12). Serotonin and its metabolite, 5-hydroxyindole acetic acid (5-HIAA), were quantified using reversed-phase (C18) HPLC with electrochemical detection. Results obtained indicate that baseline concentrations of serotonin and 5-HIAA did not increase significantly following exposure to either compound 48/80 or A23187 (p $>$ 0.05). (Abstract shortened by UMI.).

abstract: Source: Masters Abstracts International, Volume: 36-02, page: 0452.

abstract: Adviser: John F. Burka.


title: In vivo model of the response of soft -shell clam (Mya arenaria) haemocytes differentially induced by two strains of Vibrio splendidus

contributor: Berthe, Franck (Supervisory Committee Member)

contributor: Davidson, Jeff (Supervisory Committee Member)

contributor: Kibenge, Fred (Supervisory Committee Member)

contributor: Le Roux, Frederique (Supervisory Committee Member)

contributor: Markham, Fred (Supervisory Committee Member)

contributor: Siah, Ahmed (Supervisory Committee Member)

format: 229 electronic application/pdf

subject:
Biology, Cell
Agriculture, Fisheries and Aquaculture

abstract: Constantly exposed to different microorganisms, molluscs have developed means to recognize and mount defense mechanisms against potential pathogens. Conversely, pathogenic bacteria are able to subvert the host immune system by modulating their responses. Although several studies on host responses have contributed to the understanding of these interactions in various bivalves challenged with bacteria, there is no information in this respect on soft-shell clams Mya arenaria. In this study, an in vivo model of interaction between M. arenaria haemocytes and the marine bacteria Vibrio splendidus was developed by assessing a series of host responses against two bacterial strains: LGP32-GFP, derived from a pathogenic strain (LGP32) associated with oyster mortalities in France, and 7SHRW, an environmental isolate from PEI marine sediments.

abstract: Using contrast phase microscopy and flow cytometry, phenotypic responses were measured at cellular and sub-cellular levels. In addition, the expression of genes involved in physiological and immune processes was assessed with RT real time q-PCR. Also, lysozyme activity in haemolymph was studied in clams from two different origins (i.e. Ireland and Canada) challenged with the pathogenic strain. Finally, degranulation mechanisms were briefly explored in vitro. Responses of the in vivo model were assessed 24 h after injecting 4.5 x 106 bacteria/g of clam.

abstract: Increased percentages of rounded haemocytess and total numbers were found in response to both strains. However, values were significantly higher ( p ≤ 0.01) after infection with LGP32-GFP compared to 7SHRW. Also, LGP32-GFP induced markedly diminished cell adherence (p < 0.001) while no significant changes were found after infection with 7SHRW. Flow cytometry forward and side scatter profiles showed two haemocyte subpopulations: hyalinocytes and granulocytes. Granulocytes exhibited significantly higher levels of lysosomal staining (p < 0.01), revealed by the fluorescent dye LysoTracker. Following infection with LGP32-GFP, and not with 7SHRW, both subpopulations merged into a single continuous group. Also, the lysosomal content significantly decreased in hyalinocytes (p < 0.001) and granulocytes (p = 0.001), suggesting the possible occurrence of precursor cells and degranulation, respectively. Among the housekeeping genes evaluated, using the software geNorm, elongation factor 1α (EF-1α) and 2 (EF-2) had the most stable expression under  in vivo challenge with LGP32-GFP, whereas EF-1α and the ribosomal protein S-18, after challenge with 7SHRW. By using these genes as internal controls, it was detected that LGP32-GFP induced significant up-regulation of γ-actin (p < 0.001), IRAK-4 homologue ( p < 0.001) and down-regulation of TLR-2 (p < 0.001) and lysozyme-2 (p < 0.05) homologues. While actin regulation is likely associated with the cytoskeleton changes, IRAK-4 regulation would suggest activation of the NF-κB pathway. Only the down-regulation of lysozyme was significant (p < 0.05) after challenge with 7SHRW.

abstract: Lysozyme activity in haemolymph of clams from Ireland significantly increased after challenge, with a peak at 12 h (p < 0.001), while lysozyme levels did not change significantly in clams from Canada. Lysozyme levels were higher in haemocytes than in plasma. In addition, haemocytes could be induced to degranulate with the compound 48/80 suggesting a signaling pathway involving G proteins that could not be confirmed as inhibitors of such pathway did not prevent degranulation.

abstract: These results suggest specific responses at a cellular and molecular level induced by different V. splendidus strains. In contrast to 7SHRW, the strain LGP32-GFP induced marked responses at both levels that would impair the defense mechanisms of haemocytes. The differential responses assessed in this model have potential to be used as a tool to evaluate health status of clam populations.

abstract: Source: Dissertation Abstracts International, Volume: 71-08, Section: B, page: 4551.


title: In-vitro model of interaction between Vibrio splendidus and hemocytes of soft -shell clams, Mya arenaria

contributor: Brown, Laura (Supervisory Committee Member)

contributor: Johnson, Gerry (Supervisory Committee Member)

contributor: Cawthorn, Richard (Supervisory Committee Member)

format: 197 electronic application/pdf

subject:
Biology, Molecular
Agriculture, Fisheries and Aquaculture
Health Sciences, Immunology

abstract: The main goal of this thesis is to develop an in-vitro model of interaction between hemocytes of soft-shell clams and Vibrio splendidus LGP32, and investigate the early immune response of soft-shell clams both at cellular and molecular levels.

abstract: Hemocytes of soft-shell clams are actively involved in immune defence. However, they lost their pseudopodia and became rounded after V. splendidus  challenge. This phenotypic response of hemocytes (measured in percentage of rounded cells) shows a positive correlation between the ratio of hemocytes:bacteria (1:20, 1:10, 1:5 and 1:1) and the time of exposure. At a high number of bacteria per hemocyte (1:20, 1:10 and 1:5), the percentage of rounded (without pseudopodia) hemocytes increased dramatically from less than 20% in one hour to 80-90% in two. At 1:1 hemocyte to Vibrio ratio however phenotypic response was gradual (4.3% at 1 hour, 44.2% at 2 hours and 92% at 3 hours) and consequently, the ratio 1:1 was used in all the following experiments. Hemocyte viability in challenged (1:1 hemocyte to Vibrio) and control groups was very high (>91%) suggesting morphologically modified cells were alive.

abstract: In hemocytes challenged for two hours, phagocytosis and respiratory burst activities were investigated to understand the early response of hemocytes against V. splendidus. Hemocytes of soft-shell clams showed the ability to phagocytose and produce reactive oxygen/nitrogen species. This phagocytosis and respiratory burst activity of hemocytes was significantly reduced (p<0.001) post-Vibrio exposure. The reduction in phagocytosis with an increasing percentage of rounded cells suggests that hemocytes pseudopodia (cytoplasmic extensions) could play a key role in internalizing microbes. Consequently, V. splendidus seems to affect the function of hemocytes by modifying their morphology.

abstract: Besides the morphological modifications, this research also focused on the expression of genes in hemocytes post Vibrio challenge. The selected candidate genes included ribosomal proteins (rpS-15, rpS-18 and L-37), ubiquitin, receptor for activated C kinase (RACK), elongation factor 1 (EF-1) and elongation factor 2 (EF-2) as well as 18S-rRNA and actin. Our data analysis showed that actin and 18S-rRNA, usually used as housekeeping genes, were among the least stable transcripts, whereas EF-1, rpS-18 and ubiquitin were the most stable transcripts and were used as housekeeping genes in this  in-vitro interaction model. Genes associated with cytoskeleton structural stability (actin and EF-2) were among least stable genes. Consequently, the expression of both genes was quantified and showed significant up-regulation (actin p<0.001; EF-2 p<0.05) in hemocytes challenged for two hours at a ratio 1:1.

abstract: To explore the effect of V. splendidus at the molecular level, suppression subtractive hybridization (SSH) technique was used to identify the up- and down-regulated genes in hemocytes of soft-shell clams. Both forward and reverse subtracted cDNA were constructed and a total of 16,000 reads were obtained and analyzed. Identity searches in protein databases were performed using BlastX program and the transcripts were clustered to different physiological processes including structural proteins, immunity, stress proteins, apoptosis, cell process, general metabolism and signal transduction. The expression level of transcripts associated with immunity such as ficolin, killer cell lectin-like receptor, natural resistance-associated microfiche protein 1, MAPK, ferritin, HSP90 and cathepsin were quantified using RT-qPCR. Some of these genes play a key role in pathogen recognition, phagocytosis, respiratory burst activity and activating innate immune response in general. The expression pattern in most transcripts showed an up-regulation at one hour followed by a down-regulation at two and three hours.

abstract: This study showed that hemocytes of soft-shell clams are actively involved in immune defence. However, exposure to V. splendidus impaired their cellular functions suggesting the virulent nature of the bacterium. Moreover, several novel immune associated genes such as Nramp 1, ficolin, T cell receptor and Killer cell lectin-like receptor were identified in this study. Further investigations are needed to characterize and understand the role of those transcripts in the immune defence of soft-shell clams. (Abstract shortened by UMI.).

abstract: Source: Dissertation Abstracts International, Volume: 71-08, Section: B, page: 4742.


title: Inclusion and health: A study of the 2001 Participation and Activity Limitation Survey (PALS)

contributor: Crawford, Cameron (Supervisory Committee Member)

format: 147 electronic application/pdf

subject:
Education, Special
Education, Health

abstract: This thesis presents findings of a quantitative study into the relationship between inclusive education settings and the parent-reported health of more than 140, 000 Canadian children with disabilities between 5 and 14 years of age. In framing the research questions and analysis of the data, the thesis includes a critical review of the concepts of disability, inclusive education and health. The main statistical data that were used were retrieved from the children's component of Statistics Canada's 2001 Children's Participation and Activity Limitation Survey (PALS), a major post-censal survey of people with disabilities. PALS provides a wealth of information about children with disabilities in Canada. Responses to questions from PALS were selected to compile a framework to distinguish three levels of inclusiveness of educational settings: low, middle and high. Using the broad approach to health that guided the research and these three levels of educational inclusiveness, the analysis revealed that parents were more likely to report that their children with disabilities are in better general health, progress very well/well at school, interact very well/well with their peers, and frequently look forward to going to school in higher inclusive educational settings than in mid-range or lower inclusion settings. This positive trend was consistent, regardless of severity and type of disability.

abstract: Source: Masters Abstracts International, Volume: 47-06, page: 3169.


title: Independence and support:  Making parent/school relationships work for teenage students

contributor:
Murphy, Charles E. (author)
O'Donoghue, Fiona (Thesis advisor)
(Supervisory Committee Member)

format: 127 electronic application/pdf

subject: Education, Curriculum and Instruction

abstract: This qualitative study was designed to explore the role teenage students play in shaping the relationship their parents/guardians have with their high school. It examines some of the benefits and barriers to parental involvement and looks at how students can control parental access to information from the school. The site is a rural dual track (French Immersion and English) high school of 800 students situated in Prince Edward Island, Canada. The data is collected from a randomly distributed survey and subsequent interviews. There were 136 surveys completed by students in grades 10–12 as well as four interviews (conducted after the survey) with students wishing to further discuss the subject of parental involvement. The survey consisted of 14 questions both open and closed-ended and the interviews were made up of four open-ended questions. The questions on both instruments were similar and the responses were consistent between the surveys and the interview data. Through the data analysis it was discovered that the students did play a role in shaping the amount of parental involvement and the access to information that parents have. Some of the major factors governing the desire for teens to keep information from their parents centre around a desire for independence, privacy, and space.

abstract: Source: Masters Abstracts International, Volume: 43-02, page: 0371.

abstract: Adviser:  Fiona O'Donoghue.


title: Initiating recovery strategies for the Gulf of Saint Lawrence Aster (Symphyotrichum laurentianum) on Prince Edward Island and assessment of its reproductive abilities

contributor: Giberson, Donna (Supervisory Committee Member)

contributor: Silva, Marina (Supervisory Committee Member)

format: 122 electronic application/pdf

subject:
Biology, Botany
Biology, Ecology
Engineering, Environmental

abstract: The Gulf of St. Lawrence Aster (Symphyotrichum laurentianum ) (SLA) is an annual plant species endemic to the Gulf of St. Lawrence region. Due to the dynamic nature of the environment that the Gulf of St. Lawrence Aster inhabits, severe and major threats to both the Aster and its habitat exist. The Committee on the Status of Endangered Wildlife in Canada listed the species as Threatened in Canada in 2004. This status was reached due to the species' limited distribution, fluctuating population size, and to continued pressures on its habitat. Surveys have revealed that both site and population numbers have been further and drastically reduced on Prince Edward Island. In 2007 only one populated site remained with a low number of 482 individuals. It is possible that this species is on the brink of extirpation from PEI.

abstract: Recovery of this species on Prince Edward Island is feasible. Promising results related to the transplantation of greenhouse grown seedlings at four  in-situ sites demonstrated that SLA plantlets have the potential to serve as seed stock to re-establish populations. Over the two years of the transplantation experiment, the pooled overall survivorship was 52.8%. Specific site manipulations that were tested may also increase the potential survivorship of the transplants, and facilitate second-generation germination. Additionally, surveys and site assessments were conducted at 15 locations within the Prince Edward Island National Park. Although the search for new SLA populations was not successful, locations were identified in both historical and non-historical areas that yielded potential sites for future management actions to recover the species on Prince Edward Island. As well; analysis of the reproductive potential of SLA florets has revealed additional knowledge useful for future studies. Pollen exclusion experiments resulted in a significant difference in the median values of excluded versus unexcluded inflorescences. These results indicate that, as far as the production of viable seeds is concerned, SLA plants benefit more from geitonogamy and crosspollination than they do from selfing (cleistogamy).

abstract: Source: Masters Abstracts International, Volume: 50-04, page: 2241.


title: Innovation as a critical success factor in small businesses in Prince Edward Island

contributor:
MacAulay, Patricia (author)
Baldacchino, Godfrey (Thesis advisor)
(Supervisory Committee Member)

format: 108 electronic application/pdf

subject: Business Administration, Entrepreneurship

subject: Business Administration, Management

subject: Economics, General

subject: Economics, Commerce-Business

abstract: In a fast paced global economy, the competitive advantage in business rests with those that are the most flexible and best able to exploit the challenges and opportunities presented. In this environment, small businesses operating from a small island could be perceived as being at a competitive disadvantage vis-à-vis their mainland competitors. The following research however, while indicative and not representative, suggests that small businesses operating on and from a small island can successfully compete in a global environment by flexing their entrepreneurial innovation skills. My research examines locally owned and operated small businesses in the fish processing sector in Prince Edward Island, one of the more traditional sectors on the small Canadian island province. The research examines whether businesses in this sector are innovative, what types of innovative practices they employ, and whether they consider being innovative as key to their success. A qualitative approach to the research was chosen and face-to-face interviews were conducted during the summer and fall of 2009. This study suggests that small businesses in this sector are innovative as evidenced by the development of new products, new markets, niche markets, and new production technologies. While all businesses considered these innovative practices key to their success, they also rated other factors such as location, education/experience and family as important or more important to their success.

abstract: Keywords: Innovation, entrepreneurship, small islands, success, Prince Edward Island.

abstract: Source: Masters Abstracts International, Volume: 50-04, page: 2144.

abstract: Adviser: Godfrey Baldacchino.


title: Innovative dry cow therapy

contributor: Leslie, Ken (Supervisory Committee Member)

contributor: Barkema, Herman (Supervisory Committee Member)

contributor: Dingwell, Randy (Supervisory Committee Member)

contributor: Spangler, Liz (Supervisory Committee Member)

format: 242 electronic application/pdf

subject: Biology, Veterinary Science

abstract: The ability of an internal teat sealer (ITS) administered at dry-off for the prevention of new intramammary infections (IMI) and for the cure of existing IMI during the dry period was examined. In addition, incidence of clinical mastitis (CM), pattern of somatic cell count (SCC), particulate matter recovery, and milk production during the subsequent lactation were measured. The California mastitis test (CMT) was evaluated for its ability to identify cows and quarters with IMI at dry-off.

abstract: The quarter-level CMT results, interpreted in parallel to form a cow-level test result, were an effective way to identify infected cows for treatment of DCT. Using an ITS in conjunction with DCT provided enhanced protection from the development of new IMI during the dry period when compared with DCT alone, although it had no additional benefit on the cure of existing IMI. An ITS alone provided enhanced protection against the development of new environmental IMI during the dry period when compared with DCT alone. There was no reduction in the incidence of CM during the subsequent lactation when an ITS was utilized either in combination with DCT or alone. Quarters treated with ITS have significantly more particulate matter recovered during the first day postpartum when compared with quarters treated with DCT. Internal teat sealers had a negative impact on milk production during the first six months of the subsequent lactation.

abstract: In summary, ITS are an efficacious addition to dry cow programs to aid in the prevention of new IMI. The effects of ITS on milk production need to be studied further to help clarify the effect found in the current study. Lastly, the CMT is an inexpensive, effective and efficient way to identify infected cows at dry-off. This finding will be useful to assist farmers in adopting selective dry cow programs.

abstract: Source: Dissertation Abstracts International, Volume: 68-01, Section: B, page: 0142.


title: Interaction between high -fat diet, adrenalectomy and/or exercise on pancreatic B-cell function in obese Zucker (fa/fa) rats

contributor: Ihle, Sherri (Supervisory Committee Member)

contributor: Wright, Glenda (Supervisory Committee Member)

contributor: Cribb, Alastair (Supervisory Committee Member)

contributor: Wheeler, M. (Supervisory Committee Member)

format: 289 electronic application/pdf

subject:
Biology, Cell
Biology, Animal Physiology
Chemistry, Biochemistry

abstract: Young adult obese fa/fa Zucker rats are hyperinsulinemic, hyperlipidemic and insulin resistant. Pancreatic islets of fa/fa rats exhibit increased glucose sensitivity (half maximal effective glucose concentration EC50), glucokinase sensitivity (Km) and lack of mannoheptulose (MH) inhibitory action on glucose stimulated insulin secretion (GSIS). These defects are normalized by adrenalectomy (ADX) in rat chow fed rats within 2 weeks of surgery. The current study was carried out to test the hypothesis that feeding ADX rats a high fat diet would inhibit the effects of ADX on the pancreatic islet B-cells in fa/fa rats and induce adaptive changes in the lean rats.

abstract: In pancreatic islets isolated from rat chow fed fa/fa rats, ADX significantly reduced glucokinase Km and glucose phosphorylating rate (V max) compared to those of sham rats.

abstract: The MH inhibitory response was restored by ADX in fa/fa rat islets. Pancreatic triglyceride and insulin content were higher in fa/fa rat islets than in the lean rat islets and were not affected by ADX.

abstract: Feeding a high fat diet to ADX fa/fa rats significantly increased glucokinase Vmax. The restored MH inhibitory action by ADX in fa/fa rat islets was reduced by increased dietary fat. From this study it is concluded that feeding ADX a high fat diet modulated but did not eliminate ADX action on pancreatic B-cell function in fa/fa rats.

abstract: A second study was carried out to test the hypothesis that exercise would have similar effects on pancreatic B-cell function of fa/fa rats as those induced by ADX, the rationale being that both ADX and exercise increase the sympathetic nervous system activity in the peripheral tissues including the endocrine pancreas.

abstract: Exercise significantly reduced both hexokinase Km and V max in low fat fed fa/fa rats. In low fat fed lean rats, exercise reduced glucokinase and hexokinase Km without affecting the Vmax.

abstract: Feeding a high fat diet to exercised fa/fa rats significantly increased glucokinase Km and reduced both hexokinase Km and V max. The MH response was partially restored in islets isolated from high fat exercised fa/fa rats.

abstract: In sedentary lean rats, high fat diet decreased glucokinase Km, increased pancreatic islet insulin content and FFA oxidation at the lower glucose concentration.

abstract: From these studies it is concluded that ADX is more effective than exercise in preventing pancreatic islet dysfunction in obese rats due to the induction of bigger changes in glucokinase activity and islet FFA oxidation. High fat diet was able to block some of the effects of ADX and exercise. (Abstract shortened by UMI.).

abstract: Source: Dissertation Abstracts International, Volume: 61-04, Section: B, page: 1726.

abstract: Adviser:  Cathy Chan.


title: Intercalation of conductive polymers into layered structures

contributor:
Scully, Stephen F. (author)
Bissessur, Rabin (Thesis advisor)
Dahn, Doug (Thesis advisor)
(Supervisory Committee Member)

subject: Chemistry, Inorganic

abstract: The goal of this project was to investigate the host-guest intercalation chemistry of electroactive polymers with two dimensional layered compounds.

abstract: Aniline, 2-methylaniline, 2-ethylaniline, and 2-propylaniline were intercalated between the layers of iron oxychloride (FeOCl), an oxidizing structure, whereupon oxidation of the monomer afforded polyanilines between the layers. Electrical conductivity measurements indicate an increase in electrical conductivity of the nanocomposites compared with the pristine layered structure.

abstract: Aniline monomers were intercalated between the layers of hydrogen titanate (HTiO2) through an acid-base type interaction. The aniline intercalated titanate was heated in air to oxidize the aniline monomers which resulted in polymerization of the monomers to yield polyaniline intercalated titanate.

abstract: Attempts to intercalate ionically conductive polymers between the layers of titanate were unsuccessful but indicated that layered TiO2 has a strong affinity for intercalation of small positively charged species such as H+.

abstract: The highly ion conducting polymer poly(bis-(methoxyethoxyethoxy)phosphazene) was complexed with lithium triflate and intercalated into graphite oxide. The isolated product appears to be graphite reinforced polymer rather than a true intercalation compound but physical stabilization of the polymer is apparent.

abstract: The insertion of lithium ions into natural hectorite has been accomplished and a study of its ion conducting properties has shown good room temperature ion conductivity.

abstract: All materials have been characterized by powder X-ray diffraction, FTIR, TGA, and DSC where suitable. Electrical conductivities were investigated using the four probe van der Pauw technique while ionic conductivity was determined through AC impedance spectroscopy.

abstract: Source: Masters Abstracts International, Volume: 46-03, page: 1526.


title: Internal bioavailability of zinc in rainbow trout (Oncorhynchus mykiss) following chronic waterborne and dietary exposure

contributor: Burka, John (Supervisory Committee Member)

contributor: Sims, David (Supervisory Committee Member)

contributor: Dawson, Susan (Supervisory Committee Member)

contributor: Theather, Kevin (Supervisory Committee Member)

format: 170 electronic application/pdf

subject:
Health Sciences, Toxicology
Biology, Veterinary Science
Agriculture, Fisheries and Aquaculture

abstract: The principal objective of this thesis was to illuminate the internal bioavailability and the nature of interactions between the branchial and gastrointestinal routes of Zn uptake in rainbow trout (Oncorhynchus mykiss). A comprehensive analysis of tissue Zn distribution following waterborne and dietary Zn exposure, singly and in combination, was carried out. We demonstrate differences in Zn accumulation, at the tissue and subcellular levels, and distribution patterns, with the majority of the accumulated Zn being metabolically active (i.e. bioavailable). At the tissue level the carcass acted as the main sink for Zn containing 84-90% of whole-body Zn, with the intestine (3-7%) and gill (4-6%) holding the majority of the remainder. The estimated metabolically active pools were: gill 81-90%; liver 65-78%, and intestine 59-75%. Interestingly, in the two primary tissues of Zn uptake (gill and intestine) the nuclei-cellular debris fraction bound the highest amounts of Zn while in the liver heat-stable proteins were dominant. A shift in Zn distribution between the metabolically active and detoxified pools with Zn exposure was most prominent in the intestine in which the proportion of detoxified Zn increased from 25 to 41%. Interactions between the branchial and gastrointestinal uptake pathways were complex and appeared to be tissue-specific. In plasma, blood cells, and gill, uptake from water drove the Zn accumulation, while uptake from food drove the accumulation of Zn in the intestine. Both pathways appeared to contribute equally to Zn accumulation in the liver, carcass, and kidney. At the subcellular level there was minimal evidence of cross-talk between waterborne and gastrointestinal pathways. Only the branchial heat-stable, hepatic heat-denaturable, and intestinal microsomes-lysosomes fractions showed some evidence of cross-talk. We also found that the intestine was the main site for dietary Zn detoxification, while the gill had a similar role for waterborne Zn. Finally, the mitochondrial fraction was identified as a potential common target site of Zn accumulation independent of tissue and route of exposure. Overall the Zn exposure regimes employed in this research caused minimal toxicity manifested by a transient inhibition of protein synthesis in the waterborne exposure. We concluded that Zn bioaccumulation is very highly regulated in rainbow trout.

abstract: Source: Masters Abstracts International, Volume: 47-06, page: 3442.


title: Intracellular survival and multiplication of Renibacterium salmoninarum within cultured macrophages from rainbow trout (Oncorhynchus mykiss)

contributor: Markham, R.J. Frederick (Thesis advisor)

contributor: Wright, G. (Supervisory Committee Member)

contributor: Johnson, G. (Supervisory Committee Member)

subject:
Biology, Microbiology
Agriculture, Animal Pathology
Agriculture, Fisheries and Aquaculture

abstract: The intracellular survival of the causative organism of bacterial kidney disease in rainbow trout (Oncorhynchus mykiss) macrophages was investigated. Bacterial kidney disease, an economically important disease of farmed and wild salmonid fish, is caused by the small, rod-shaped, Gram-positive bacterium Renibacterium salmoninarum.

abstract: Evidence for the intracellular survival of Renibacterium salmoninarum for seven days and for the intracellular multiplication of the bacterium for four or five days was shown by both bacteriological and ultrastructural methods. Bacteria were contained within membrane-bound vesicles and no significant prevention of phagosome-lysosome fusion by bacteria was found. Thus it appeared that Renibacterium salmoninarum survived due to an innate ability to resist degradative mechanisms of rainbow trout macrophages. The present results justify the classification of Renibacterium salmoninarum as a facultative intracellular parasite. (Abstract shortened by UMI.).

abstract: Source: Masters Abstracts International, Volume: 32-01, page: 0181.


title: Intraepithelial intestinal lymphocytes and enterocytes in intestinal immune response

subject: Health Sciences, Immunology

abstract: Source: Masters Abstracts International, Volume: 40-07.


title: Investigating the suitability of northern mummichog (Fundulus heteroclitus macrolepidotus) for the assessment of cumulative and non-point source pollution in Prince Edward Island estuaries

contributor:
Finley, Megan A. (author)
van den Heuvel, Mike (Thesis advisor)
(Supervisory Committee Member)

format: 123 electronic application/pdf

subject:
Biology, Ecology
Health Sciences, Toxicology
Environmental Sciences

abstract: The overall objective of this study is to evaluate the use of the estuarine species, the northern mummichog (Fundulus heteroclitus macrolepidotus ) as a monitoring species for the detection of the cumulative impacts of agricultural land use in Prince Edward Island (PEI). The first study investigated the spatial and temporal variability of the somatic indices used to describe fish performance, specifically measures of energy use and storage, as indicated by liver and gonad sizes, and the overall condition of the fish. Three estuaries were sampled once in December 2006 and then on a weekly basis from May through July, with additional sampling periods in August and September 2007 to examine the temporal variability. Spatial variability was assessed by sampling populations at five spots along an estuary at a single time period. Results showed considerable variation both within and between sites over the reproductive season as well as between sites within an estuary. Repeated sampling is required to assess reproductive output in this species and densities of adults and young-of-the-year (YOY) may be the best indicator of environmental stress.

abstract: The second study was an effects-based assessment conducted in seven estuaries spanning a range of land-use, agricultural, industrial and/or municipal, and potential nutrient loadings. Over the course of the summer of 2007 somatic measures of fish performance, measures of population density and structure, and biochemical measures of exposure were monitored. The somatic and population measurements focused on the three main processes impacting population integrity: growth, reproduction, and survival; in addition to establishing a potential cause-effect relationship between stressor and response. Mummichog populations appear to be most affected in heavily eutrophic environments. The most obvious manifestation of this is an increase in recruitment and overall population number. At one site there was a significant increase in fecundity and gonad size; however survival of YOY or eggs appears to be impacted as indicated by lower YOY:adult ratios. Multivariate analysis of environmental variables clearly separates the sites on the basis of both eutrophication indicators such as nitrogen loading, chlorophyll and Ulva density in the first principal component and sediment variables in the second principle component. It is thought that the amount of fine sediment at this site may have affected YOY survival. Interestingly, fish found in these higher agriculture areas also experienced significantly lower in vitro steroid production. This decline in steroid production does not appear to have a detrimental effect on the reproductive potential of adult mummichog suggesting a possible masking effect of the nutrient enrichment.

abstract: Overall, these studies have shown that many of the performance measures typically used in environmental effects monitoring programs, fish condition and reproduction, are not efficient at determining differences among sites. This is likely due to the prolonged reproductive period followed by a short period of winter preparation. However, the abundance of mummichog found at a site combined with lower species richness may be a good indicator of environmental health.

abstract: Source: Masters Abstracts International, Volume: 47-06, page: 3385.


title: Investigating vectors for aquatic invasive species of tunicates in the Canadian shellfish aquaculture industry

contributor: Greenwood, Spencer (Supervisory Committee Member)

contributor: Ayles, Heather (Supervisory Committee Member)

contributor: Therriault, Thomas (Supervisory Committee Member)

contributor: Spangler, Elizabeth (Supervisory Committee Member)

format: 2012 electronic application/pdf

abstract: The potential spread of Didemnum vexillum through aquaculture transfers of Pacific oyster (Crassostrea gigas) was investigated on the Sunshine Coast and the West Coast of Vancouver Island, BC. Pacific oysters from infested areas are regularly transferred for processing to non-infested areas thereby posing a risk of spreading D. vexillum to new areas. This observational study used concepts of the Hazard Analysis Critical Control Point (HACCP) methodology to identify points (control processes, CPs) where the clusters of oysters received manipulations that could alter the amount of epibiont fouling, notably D. vexillum. Three control processes (CPs) were identified: 1) the harvesting procedure, 2) transportation from the harvesting area to the processing plant, and 3) shucking of the oysters and depositing fouled shells in non-infested waters. The percentage coverage of D. vexillum on oyster clusters was evaluated at each CP for product originating from two aquaculture sites, Lemmens Inlet and Okeover Inlet. The results from the assessment demonstrated a significant loss of fouling on C. gigas clusters at both sites from Post-Harvesting (CP1) to Post-Shucking (CP3).

abstract: A NR viability assay was developed using Botrylloides violaceus , which is an invasive colonial tunicate in PEI, as a proxy to the colonial tunicate D. vexillum as it is not locally found on PEI. B. violaceus was collected from various locations around PEI and mortality could be determined under light microscopy by assessing filtering and reaction to tactile stimuli as clinical markers. A total of 32 B. violaceus segments (3 cm2) were assessed for viability by comparing a treatment (dead - acetic acid immersion) and a control (alive) group by evaluating NR uptake. Determination of viability in B. violaceus  was successful in 100 % of experiments. All of the control group were alive, demonstrating a response to tactile stimulus and a noticeable amount of stain inside the zooids. All treatment groups were dead, demonstrated by the lack of staining and non response to tactile stimulus. A total of 27 fouled clusters containing C. gigas and D. vexillum  were collected from an aquaculture lease, Lemmens Inlet, BC, for an aerial exposure comprised of 9 equally divided treatments (0 (control), 0.5, 1.5, 3, 6, 12, 24, 48 and 72 hours). Three segments of D. vexillum  were removed from C. gigas and evaluated with the NR stain protocol. Preserved tissues were analyzed and showed no stain uptake for all segments, including the control. This finding demonstrates that  D. vexillum has a high tolerance for uncommon situations and may reflect their ability to enter a dormant state during adverse environmental conditions.

abstract: In the Montague River estuary, PEI, Ciona intestinalis is the dominant tunicate AIS and is now present in adjacent bays. Removal of C. intestinalis from mussels in processing plants can release gametes into effluent water. Two separate trials in this experimental study focused on the effect of turbidity and flow found in effluent water on C. intestinalis egg fertilization. The first trial evaluated the effect of turbidity (0, 300, 600 and 1200 NTU), and the second evaluated the effect of turbidity (0, 300, 600 and 1200 NTU) combined with water flow (0.9583 L/s).  These trials illustrate that regardless of turbidity and flow rate a potential propagule pressure still exists when removing tunicates from mussels within processing plants.

abstract: Tunicates have a detrimental effect on the mussel industry by fouling aquaculture gear, product and by increasing labour time and cost of culture. Management to maintain an economically sustainable aquaculture industry via optimized husbandry practices, from a grower and processor perspective, is required to lessen the impact of current tunicates and to reduce the potential impact from new AIS threats. The continued monitoring, education and communication to minimize, if not stop, the ongoing spread is a necessity, especially for shellfish growers in PEI and BC who are already combating tunicate invaders.  (Abstract shortened by UMI.).

abstract: Source: Masters Abstracts International, Volume: 50-04, page: 2214.

abstract: Adviser: Jeff Davidson.


title: Investigation of anti-arthritic effects of a new glucosamine formulation (ONC114)

contributor: Milner, James (Supervisory Committee Member)

contributor: Ireland, William (Supervisory Committee Member)

contributor: Gaskill, Cynthia (Supervisory Committee Member)

contributor: Ryan, Dan (Supervisory Committee Member)

format: 160 electronic application/pdf

subject: Biology, Veterinary Science

abstract: This study investigated the effectiveness of a new glucosamine hydrochloride formulation in osteoarthritic dogs. The study was divided into two phases. The first phase of the study was conducted as a randomized, double blind placebo controlled clinical trial for a 6 month period. Thirty dogs, who exhibited clinical lameness due to osteoarthritis in one limb, were randomly allocated into 3 groups: the new formulation of glucosamine (ONC114), glucosamine alone and placebo control groups. Measurements of locomotive performance included objective force plate gait analysis, subjective orthopedic examination, radiographic examination and degree of lameness assessed by owners. These evaluations as well as hematological and biochemical evaluations were obtained during 4 evaluation times: pretreatment, the 6th week, the 3rd month and the 6th month. After 6 months, the placebo control group was eliminated. During the second phase of the study the dogs in the ONC114 and the glucosamine groups were continued on their treatment protocol. Dogs in the placebo control group were randomly allocated into the crossover ONC114 and glucosamine treatment groups. The second phase of the study continued for additional 6 months with evaluation times at the 9th month and at 1 year. (Abstract shortened by UMI.).

abstract: Source: Masters Abstracts International, Volume: 42-02, page: 0540.

abstract: Adviser: Caroline L. Runyon.


title: Investigations of the UV-A photochemistry of the pesticide azinphos-methyl

contributor:
Yeasmin, Lovely (author)
Wagner, Brian (Thesis advisor)
(Supervisory Committee Member)

format: 112 electronic application/pdf

subject: Chemistry, Physical

abstract: This project focused on the investigation of the photochemistry of the pesticide azinphos-methyl (AZM) using various techniques to explore the kinetics and reaction mechanism of its photolysis with UV-A (290 to <400 nm) light sources in the laboratory and natural environment (in natural water and under direct sunlight). A key aspect of this project was the identification of the intermediate photoproduct involved in the reaction mechanism as well as the final photoproduct(s) of AZM photolysis. Fluorescence spectroscopic techniques were used to study the kinetics of the photodegradation of AZM in a number of solvents. AZM photolysis results with various excitation wavelengths in the fluorimeter showed that complete photodegradation of the pesticide occurred in the aqueous system. In other solvents, complete conversion of the AZM was not observed, at least over the time frame used. On the other hand, kinetic studies using a photoreactor with an excitation wavelength of 350 nm showed AZM to be completely degraded. It was observed that the reaction followed consecutive first-order kinetics (A → B → C) giving a highly fluorescent intermediate B and a relatively non-fluorescent final product(s) C in all the solvents of interest. The solvent polarity effect on the photolysis of the pesticide in protic and aprotic media was examined, which showed no clear dependence on solvent polarity for the growth of the highly fluorescent intermediate (A → B), but a significant correlation was observed for the further photolysis of this intermediate (B → C). In aqueous acid buffer solution, AZM photolysis was very slow compare to that in neutral solution. The observed photolysis of AZM was also observed under direct sunlight in natural water. UV-vis, fluorescence, NMR, HPLC and LFP techniques were used to investigate and identify the intermediate and the final photoproducts. A mechanism of AZM photolysis in the laboratory environment (in water and methanol) is proposed. In this study, N-methyl anthranilic acid was identified as the highly fluorescent intermediate photoproduct. This intermediate photoproduct undergoes further photodegradation processes producing aniline and/or N-methyl aniline, relatively non-fluorescent final product(s). Benzazimide was identified as one of the final photoproducts; it is also relatively non-fluorescent, but is produced by a separate pathway from that producing the N-methylanthranilic acid as the highly fluorescent intermediate. It was also proposed that AZM photolysis promoted by sunlight follows the same mechanism found in the laboratory system. The observed photodegradation of AZM by sunlight has important implications for its fate in the environment.

abstract: Source: Masters Abstracts International, Volume: 45-03, page: 1506.


title: The association between bulk tank milk analysis for raw milk quality and on-farm management practices

contributor: Jayarao, Bhushan (Supervisory Committee Member)

contributor: Lewis, Jeff (Supervisory Committee Member)

contributor: Wichtel, Jeff (Supervisory Committee Member)

format: 186 electronic application/pdf

subject: Agriculture, Food Science and Technology

subject: Biology, Microbiology

abstract: The primary objective of this thesis was to investigate the association between raw milk bacterial quality and on-farm management practices in Prince Edward Island dairy herds. Secondary objectives included identification of lipolytic and proteolytic bacteria in pasteurized milk and investigation of the role of mastitis associated pathogens in elevated bacterial counts in bulk tank milk (BTM).

abstract: To achieve the primary objective, 4 studies were conducted. In the first study, BTM quality was evaluated biweekly in all PEI dairy herds over a two year period (March 2005 to March 2007), using total aerobic (TAC), preliminary incubation (PIC), laboratory pasteurization (LPC), coliform (CC), and somatic cell (SCC) counts. The results of this study showed weak correlations among the bacterial counts which suggests that each count gives different information in relation to management practices. With the exception of SCC, other milk quality parameters had moderate to high coefficient of variation, which indicates that herd assessments should not rely on a single measurement. In general, there was no consistent seasonal pattern over the 2 year study period for TAC, PIC, and LPC, although all counts tended to be low in winter. The CC and SCC were always highest in summer.

abstract: In the second study, the association between laboratory test results and on-farm management practices was assessed using data from a mail out survey. The survey covered 4 main areas: general farm demographics and management, cow cleanliness and hygiene, milking procedures and mastitis control, and equipment maintenance and cleaning. The response rate of the survey was 65%. The TAC and PIC were positively associated with the amount of soiling on the teats prior to udder preparation and manual cleaning of the bulk tank. Additionally, various methods of premilking udder preparation were important, with pre-dip followed by drying being superior to other methods in reducing the bacterial counts. The LPC was positively associated with the presence of a plate cooler and inadequate frequency of acid washing, whereas having a water purification system was protective. Finally, for CC, clipping udder hair and automated washing of the bulk tank were protective, whereas increasing herd size and inadequate frequency of acid washing were risk factors.

abstract: In the third study, the association between BTM bacterial quality and management practices was further investigated using a case control study (January 2006 to May 2007). Cases and controls were defined based on the results of all bacterial counts. On-farm evaluation included observation of basic management practices, evaluation of equipment hygiene and cooling efficiency, and scoring of cow and environmental hygiene. The results identified udder hygiene, milking system wash solution temperature and chemistry, and milk house water quality as important factors for bacteriological quality of BTM.

abstract: In the forth study, four case-control groups were evaluated to determine specific on-farm risks for each of TAC, PIC, LPC, and CC. The results of this analysis showed that TAC and PIC were mainly associated with cow and stall hygiene, washing the teats with water and not using teat pre-dip, and having dirty teats after udder preparation. The LPC and CC were related to equipment hygiene, with high counts being associated with low temperature of the cleaning solution, high water hardness score, and high alkalinity of the alkaline detergent wash.

abstract: One of the secondary objectives was to characterize lipolytic and proteolytic bacteria in pasteurized milk. In this study, BTM from 100 farms was subjected to laboratory pasteurization. The lipolytic and proteolytic activity of the surviving bacteria was determined under conditions that approximate poor refrigeration. The predominant isolates from pasteurized milk were Gram-positive rods (83% mainly Bacillus spp.), followed by Gram-positive cocci (17% mainly Staphylococcus spp.). Most of the isolates showed proteolytic or lipolytic activity or both, which indicate their potential of causing spoilage of pasteurized milk.

abstract: Another secondary objective was to investigate the role of mastitis-associated pathogens in elevated TAC in BTM. In 17 (19%) out of 89 samples that had high (>10,000 cfu/ml) TAC, mastitis-associated pathogens had a significant proportional contribution (≥0.25) to the TAC. While the majority of high bacterial counts were not associated with mastitis organisms, mastitis-associated pathogens can be present in very high numbers in bulk tank milk and can contribute to elevated TAC.

abstract: In conclusion, TAC, PIC, LPC, and CC are of considerable value for identifying practices that could influence milk quality. Lipolytic and proteolytic bacteria which survive pasteurization, particularly Bacillus spp., represent a big challenge to the shelf life of pasteurized milk. Although not common, mastitis associated pathogens could be associated with elevated TAC in BTM.

abstract: Source: Dissertation Abstracts International, Volume: 70-08, Section: B, page: 4547.


title: The association between the introduction of a province-wide school nutrition policy and food consumption in elementary school children on Prince Edward Island

contributor: Bryanton, Janet (Supervisory Committee Member)

contributor: MacLellan, Debbie (Supervisory Committee Member)

contributor: McKenna, Mary (Supervisory Committee Member)

format: 102 electronic application/pdf

subject:
Health Sciences, Nutrition
Health Sciences, Public Health
Education, Health

abstract: Although the majority of Canadian provinces have now adopted province-wide school nutrition policies in an effort to improve children's eating habits and reduce childhood overweight, there has been little evaluation of healthy eating policies across the country. Nutrition policies for elementary schools in Prince Edward Island were adopted by all three school districts in 2005-2006, referred to as the PEI School Nutrition Policy in this thesis. This purpose of this study was to describe food consumption of those grade five and six students participating in the Eating Behaviour Survey in 2007 and to examine the association between any changes in food consumption and the implementation of the school nutrition policy (2001/02 vs. 2007). An in-class survey was used to describe food intakes according to grade and gender for all grade 5 and 6 children in PEI in 2007 (n=2026). A quasi-experimental, pre-test–post-test design was then used to compare food consumption data from a subset of 11 schools which were included in both a pre-policy (2001/02) survey and the post-implementation survey (2007) (n=1533). Study hypotheses were that (1) daily intakes of Milk and Alternatives (MA) and Vegetables and Fruit (VF) will be higher and intakes of low nutrient density foods (LNDF) will be lower following implementation of the PEI School Nutrition Policy compared to pre-implementation; (2) students will be more likely to consume adequate amounts of MA, VF following policy implementation compared to pre-implementation and (3) students will be less likely to consume three or more servings of LNDF following policy implementation compared to pre-implementation. Hierarchical linear modelling was then used to assess changes in food consumption between 2001/02 and 2007, with survey year as a fixed effect and gender, grade and the difference in students' total daily number of food servings between the two time periods as covariates.

abstract: Results indicated that students in 2007 were more than twice as likely to report consuming less than 3 servings of LNDF compared to those in 2001/02 (OR=2.14 [95% CI 1.63, 2.83]). Survey year was also a significant predictor of whether or not students met CFG recommendations for Milk and Alternatives and Vegetables and Fruit. Students who were surveyed in 2007 were 1.3 times more likely to consume the recommended servings of Milk and Alternatives (p<0.05) and 1.5 times more likely to consume the recommended servings of Vegetables and Fruit than students in 2001/02.

abstract: Study results provide support for our hypotheses in that the introduction of the PEI School Nutrition Policy has been associated with a significant reduction in the consumption of low-nutrient density foods and a modest increase in the consumption of healthier choices from the Vegetables and Fruit and Milk and Alternatives food groups. The results thus underscore the importance of school nutrition policies, which modify the school food environment through the restriction of 'poor choices', in improving children's diet quality and their overall health. Findings are also consistent with a growing number of studies demonstrating the impact of changes to the school food environment on student food and nutrient intakes. While reducing unhealthy foods is a positive change to the school food environment, the lack of improvement in healthy choices may suggest that a more comprehensive intervention is needed where healthy choices are made readily available to students.

abstract: Source: Masters Abstracts International, Volume: 47-06, page: 3531.


title: The conservation value of hedgerows to small mammals on Prince Edward Island

contributor: Lacroix, Christian (Supervisory Committee Member)

contributor: Guignion, Daryl (Supervisory Committee Member)

contributor: Forbes, G. (Supervisory Committee Member)

format: 204 electronic application/pdf

subject:
Biology, Ecology
Agriculture, Forestry and Wildlife

abstract: Hedgerows are an important landscape feature on Prince Edward Island, Canada and are often the only forested links between isolated forest fragments. Although recent studies have examined the effects of fragmentation on small mammals on Prince Edward Island (e.g., Silva et al. 2000, Silva 2001), none have addressed the use of hedgerows by small mammals. A total of 13 hedgerows and 12 forest fragments in three sites located in central Prince Edward Island were studied from May to September 2001. Hedgerows varied in length, between 70 m and 720 m, and width between 9.4 m and 31 m. Fragment area varied from 0.006 km2 to 0.560 km2. Large Sherman live traps were placed in the center of hedgerow vegetation at 10 m intervals throughout the length of the hedgerow, while a grid configuration was used in forest fragments with the maximum area sampled being 6400 m 2. Within each study site, hedgerows and forest fragments were sampled simultaneously. (Abstract shortened by UMI.).

abstract: Source: Masters Abstracts International, Volume: 41-02, page: 0470.

abstract: Adviser: Marina Silva.


title: The critical skills of a beginning principal

contributor: Hopkirk, Gerry (Supervisory Committee Member)

format: 131 electronic application/pdf

subject: Education, Administration

abstract: This qualitative study describes the lived experiences of the researcher and 6 principals in the Eastern School District in Prince Edward Island and their perspectives on the critical skills necessary for a successful start to the principalship. This thesis also examines the professional development opportunities that should be organized for this novice group of administrators. The researcher used a personal journal and triangulated this data with a focus group interview. The results clearly outlined that the critical skills could be easily organized into technical, socialization and self-awareness categories with the latter two areas clearly of the most importance to a beginning principal. The professional development opportunities seemed to centre on the need for small group discussions amongst homogenous groups to faclilitate open and honest communication. Recommendations are made to the Eastern School District to focus future professional development activities in the area of communication through small group discussions.

abstract: Source: Masters Abstracts International, Volume: 41-02, page: 0345.

abstract: Adviser: Gerry Hopkirk.


title: The development and application of DNA markers for the American lobster, Homarus americanus

contributor: Barkema, Herman (Supervisory Committee Member)

format: 210 electronic application/pdf

subject: Biology, Molecular

abstract: The American lobster (Homarus americanus) fishery is a multi-million dollar industry, along the north Atlantic coast of North America. Sustainable management practices require information on the nature and degree of genetic diversity that exists within and among lobster populations. The objectives of this study were twofold: first, to identify and characterize candidate molecular markers; and second, to test populations off Prince Edward Island, Canada for homogeneity using genetic markers. Direct (diploid) sequencing of PCR amplicons was used to screen for allelic variation within an intron of the cytoplasmic gelsolin (CyG) gene. It was observed that diploid sequencing can be useful as a screening tool for allelic variation, however additional complimentary molecular analyses are required to accurately characterize length polymorphisms (indels) such as the microsatellites identified within an intron of CyG. Candidate CyG alleles identified by diploid sequencing were characterized further by sequencing of cloned amplicons containing one of the microsatellite regions and generated using low fidelity (Taq) and high fidelity (Pfu) DNA polymerases. Among eight individuals analyzed, seven alleles were identified from a total of 45 Taq-generated clones. Among 54 Pfu-generated clones only three alleles were identified. Discrepancies between the results were attributed to nucleotide incorporation errors that occurred either during the PCR, cloning or sequencing process. The genetic analysis of population variability is dependent on the quality of the data produced therefore all measures to minimize nucleotide errors and an independent verification method should be performed. A gene-associated microsatellite locus identified within the 3' untranslated region (UTR) of the crustacean hyperglycemic hormone B gene (CHH-B) was used to examine the genetic variation and population structure of lobsters from six geographic locations off PEI. There were extensive polymorphisms within the locations and allelic richness values standardized for N=18 indicated there were differences in the number of alleles between populations. All populations were in Hardy-Weinberg equilibrium (HWE) and no significant population substructure occurred among the locations (FST 0.05), suggesting mixing is occurring among the locations. Sequences for two genes involved in arthropod immune function were isolated from H. americanus. A 2672 by full length cDNA encoding prophenoloxidase (proPO) was obtained from haemocytes by reverse transcription polymerase chain reaction. The deduced polypeptide sequence of 673 amino acids showed highest similarity with other known decapod proPOs. A 3902 by genomic sequence for a Toll-like gene (Ha-Toll) was identified using nested inverse PCR. A 196 amino acid sequence was predicted and shows similarity to several insect Tolls as well as a recently identified chelicerate Toll. This novel sequence data represents two genes intimately involved in immune function and creates a platform for future studies in population health and evolutionary analyses in homarid species. The application of genetic markers provides information concerning a species' genomic diversity. Three genetic markers as well as two novel gene sequences for H. americanus  were identified in this thesis. A preliminary study with one microsatellite marker was conducted to examine the genetic variability between north and south shore lobster populations off Prince Edward Island. Although the results suggested a panmictic population, additional studies using a larger number of genetic markers and greater sample sizes should follow to further test the hypothesis of genetic homogeneity and strengthen the conclusions made concerning lobster stocks.

abstract: Source: Dissertation Abstracts International, Volume: 68-01, Section: B, page: 0099.


title: The development of a codon-optimized DNA vaccine for enterotoxigenic Escherichia coli in swine

contributor: Markham, R.J. Frederick (Thesis advisor)

contributor: Morrison, Maggie (Supervisory Committee Member)

contributor: Ikede, Basil (Supervisory Committee Member)

format: 176 electronic application/pdf

subject:
Biology, Microbiology
Biology, Animal Physiology
Biology, Veterinary Science

abstract: Enterotoxigenic E. coli (ETEC) is an economically important pathogen in the swine industry. These E. coli express the F4+ fimbriae and adhere to enterocytes of the small intestine of young pigs, causing neonatal and post weaning diarrhea through the production of enterotoxins. F4+ E. coli are associated with higher mortality rates, increased treatment costs for morbid animals and negative impacts on the revenue of producers. There is currently no commercially available vaccine that offers protection from F4+ E. coli  in post weaning pigs and cheaper alternatives are currently being sought that offer protection to neonates.

abstract: DNA vaccines represent a novel technology for disease prevention. They consist of an expression plasmid that contains the gene encoding a protective antigen. Upon delivery to a host the vaccine is internalized by individual cells, which express the gene and initiate an immune response. DNA vaccines possess unique qualities such as an ability to stimulate both humoral and cellular immunity and an apparent ability to overcome maternal antibody interference.

abstract: An expression-optimized DNA vaccine encoding faeG, the gene for the major subunit of the F4 fimbrial antigen, was constructed to be expressed specifically in swine. The faeG gene was redesigned for optimal expression in swine through the alteration of its codon bias to reflect swine codon preference. This involved recoding the majority of the  faeG coding sequence. In addition, an endogenous prokaryotic signal sequence was removed from the 5' coding sequence and a eukaryotic Kozak translation initiation sequence was included at the AUG start codon. These changes resulted in alteration of over 78% of the native faeG codons. A single-step recursive PCR was used to construct the newly redesigned faeG and this involved the synthesis and assembly of a number of oligonucleotides which span the length of faeG. The reaction conditions of recursive PCR were optimized which allowed for efficient construction of the expression-optimized faeG gene de novo that was both cost-effective and reproducible.

abstract: The expression-optimized faeG gene (sfaeG) was inserted into a novel expression vector (pVac), completing the vaccine construct. A number of vaccine constructs were subsequently created that carried  faeG genes with varying codon biases in relation to swine codon preference. The effect of codon bias on expression was examined in vitro by transfecting swine fibroblasts with the vaccine constructs and measuring FaeG expression using immunoprecipitation. It was observed that codon-bias had a significant positive impact on in vitro FaeG expression. Indeed, FaeG expression in cells transfected with sfaeG was 40-fold greater than cells transfected with a un-modified faeG vaccine construct. While altering codon bias to suit swine did enhance FaeG expression, the increases were not directly proportional to the degree of optimal codon usage.

abstract: Finally, DNA vaccines encoding sfaeG and wild-type  faeG, were tested in vivo in mice, using purified F4+ fimbriae and an empty expression plasmid as controls. Mice vaccinated with the DNA vaccine encoding sfaeG responded more quickly and demonstrated a significantly greater humoral and cellular immune response (p < 0.05) than mice vaccinated with the wild-type faeG DNA vaccine, thus demonstrating that increased expression is correlated with stronger immune responses.

abstract: Source: Masters Abstracts International, Volume: 45-03, page: 1406.


title: The diagnostic value of postmortem eyefluid analysis in dogs, cats and cattle

contributor: Bellamy, J. E. C. (Supervisory Committee Member)

contributor: Daoust, P. Y. (Supervisory Committee Member)

contributor: Honor, D. J. (Supervisory Committee Member)

contributor: Oligvie, T. H. (Supervisory Committee Member)

subject: Engineering, General

abstract: Source: Masters Abstracts International, Volume: 40-07.


title: The dose-response relationship of morphine in a zebrafish ( Danio rerio) model

contributor: Wright, Glenda (Supervisory Committee Member)

contributor: Burka, John (Supervisory Committee Member)

contributor: Lemke, Kip (Supervisory Committee Member)

format: 121 electronic application/pdf

subject:
Health Sciences, Pharmacology
Biology, Veterinary Science

abstract: Previous experiments in zebrafish (Danio rerio) have shown that a noxious ("painful") stimulus results in behavioural changes, namely a marked decrease in swimming activity. Analgesics may be effective at blocking this behavioural change but there is little evidence-based data regarding the efficacy of analgesics in fish. Before any analgesic can be used, a dose-response relationship must be demonstrated and first needs to be shown with morphine, the gold standard analgesic. I tested a model using subcutaneous acid injection as the noxious stimulus which has previously been shown to decrease swimming activity in zebrafish. Fish activity, before and after treatment, was recorded with a video camera and analyzed with Loligo ® software. To alleviate this response, morphine was administered intraperitoneally at doses of 1,3,10,30, or 100 mg/kg in an attempt to show a dose-response relationship. Fish receiving doses of 1 or 100 mg/kg came from a different source and behaved so differently that their results could not be included in the statistical analysis. Acetic acid (5%) at both 5 and 10 μL significantly reduced activity in zebrafish in comparison with saline injected controls (p<0.0001), with the difference scaling with stimulus intensity. Morphine at doses of 10 and 30 mg/kg was effective at attenuating the decrease in activity associated with the noxious stimulus. The ED 50 of morphine was 12.3 ± 1.2 mg/kg (90% C.I. 9.7-15.5). Activity of 10 mg/kg morphine/acid injected fish was not significantly different from control fish that did not receive the noxious acid injection at 60 and 90 min post injection (p=0.39). Activity of morphine-injected controls (no noxious stimulus) did not differ significantly from saline control fish at 60 and 90 min post injection (p=0,88). Effective doses of morphine (10 and 30 mg/kg) were then injected in conjunction with naloxone, a known opioid antagonist. Naloxone, at both 10 and 30 mg/kg, was effective at attenuating the analgesic effect of 10 mg/kg morphine. These results show that morphine acts dose-dependently on opioid receptors to reverse behavioural changes associated with a noxious event in zebrafish. These results are consistent with other studies on zebrafish and confirm the robustness of the acetic acid-zebrafish model in testing analgesic drugs.

abstract: Source: Masters Abstracts International, Volume: 50-04, page: 2399.

abstract: Advisers: Don Stevens; Collins Kamunde.


title: The effect of FulfillRTM (pymetrozine) on green peach aphids (Myzus persicae Sulzer) in comparison to current aphicides, and the role of adjuvants for use with this aphicide

contributor: Giberson, Donna (Supervisory Committee Member)

format: 97 electronic application/pdf

subject:
Agriculture, Agronomy
Biology, Botany
Biology, Entomology

abstract: Fulfill® 50 WG is a new highly selective aphicide that contains the active ingredient pymetrozine. Pymetrozine has a unique mode of action. Instead of acting as a general toxin, this aphicide inhibits feeding in aphids which consequently leads to starvation. This aphicide is currently being considered for registration in Canada. The main objectives of this study were: (1) to verify that aphids cease feeding after exposure to Fulfill®, (2) to determine, using scanning electron microscopy, whether Fulfill® causes any morphological changes to the aphid proboscis,  (3) to compare the efficacy of Fulfill ® with the currently used insecticides, Monitor® and Pirimor® under PEI conditions and (4) to determine which adjuvant, if any, increases the efficacy of Fulfill®.

abstract: All pesticide applications occurred in the field with a tractor mounted sprayer. In the lab studies, aphids were placed onto leaves that were sprayed in the field, then were brought to the lab and placed in vials of water. (Abstract shortened by UMI.).

abstract: Source: Masters Abstracts International, Volume: 42-02, page: 0513.

abstract: Adviser: Christian Lacroix.


title: The effect of formal leadership training on the leadership styles of police field trainers

format: 106 electronic application/pdf

subject:
Sociology, Criminology and Penology
Education, Vocational

abstract: This ex post facto causal comparative based study examined if any relationships existed between the attendance of the Supervision Level 1 training course held at the Atlantic Police Academy and the leadership style profiles of police field trainer attendees. Two biographically matched samples of 35 field trainers (trained and untrained), from the Maritime provinces, were given the Multi-factor Leadership Questionnaire (MLQ 5X). The 26 returned surveys were used to determine the leadership profiles along 3 leadership style domains: transformational, transactional and laissez-faire (Bass & Avolio,1997). The results were examined using a matched sample t test (25 df, .05 alpha) to determine the degree of differences between the two groups. No statistically significant differences were found, but the direction of the differences were consistent with previous research showing that leadership styles can be positively affected by training (Bass & Avolio, 1997). The laissez-faire score (1.782) approached statistical significance. Discussion of the need for future research in this area of police education.

abstract: Source: Masters Abstracts International, Volume: 43-02, page: 0393.

abstract: Adviser:  Gerry Hopkirk.


title: The effect of meconium and amniotic fluid on alveolar macrophage function

contributor: Hoskin, David (Supervisory Committee Member)

contributor: Lewis, Jeffrey (Supervisory Committee Member)

contributor: Ihle, Sherri (Supervisory Committee Member)

format: 169 electronic application/pdf

subject:
Biology, Cell
Health Sciences, Pathology

abstract: The meconium aspiration syndrome (MAS) is an important cause of respiratory distress in newborn infants. Although numerous studies have examined prophylactic and therapeutic strategies for MAS, relatively little is known about the cellular pathophysiology of this syndrome, particularly in regard to alveolar macrophages. Since the meconium aspirated by neonates is necessarily diluted with amniotic fluid, the aim of this study was to examine the effect of both meconium and amniotic fluid on phagocytosis, respiratory burst, and production of proinflammatory cytokines in rat NR8383 alveolar macrophages.

abstract: Meconium was obtained from both human and equine neonates, and similar effects on the phagocytic and respiratory burst activity were observed following exposure of alveolar macrophages to meconium from either species.

abstract: The effect of meconium-exposure on the respiratory burst response in alveolar macrophages was quantified using flow cytometry to measure oxidation of dichlorofluorescin diacetate. (Abstract shortened by UMI.).

abstract: Source: Masters Abstracts International, Volume: 43-02, page: 0524.

abstract: Advisers:  Alfonso Lopez; Fred Markham.


title: The effect of mitigation strategies for the clubbed tunicate  Styela clava on mussel collectors

contributor: Wichtel, Jeff (Supervisory Committee Member)

contributor: Stryhn, Henrik (Supervisory Committee Member)

contributor: Tremblay, Réjean (Supervisory Committee Member)

contributor: Berthe, Franck (Supervisory Committee Member)

format: 83 electronic application/pdf

subject: Agriculture, Fisheries and Aquaculture

abstract: The culture of the blue mussel Mytilus edulis in Prince Edward Island (PEI) began in the 1970's. Production has since increased, such that PEI produces 80% of Canada's cultured mussels and in 2004 accounted for over $36 million CND. Recently, an increase in fouling organisms has lead to a change in the culture methods used by mussel growers across PEI. The focus of this study is on two fouling organisms that have become pests in several mussel growing areas; the invasive solitary clubbed tunicate  Styela clava and several algae species collectively referred to as macroalgae (identified as Cladophora, and Enteromorpha ). These are specifically devastating for the seed collection stage, and a primary objective of the mussel industry is to eradicate both with the application of one treatment.

abstract: The goal of our first study was to examine the effects of two chemical treatments on S. clava, macroalgae, and mussel seed at the seed collection stage. The treatments used were 5% acetic acid and 4% hydrated lime. The former is used to mitigate S. clava on mussel socks, while the latter is used to eradicate starfish from collectors and socks. Results strongly support 4% hydrated lime as the treatment of choice for controlling tunicate and macroalgae fouling at the seed collection stage. Collectors receiving this treatment had the highest mussel abundance and the lowest tunicate abundance, and had lower macroalgae weights than untreated control collectors. In addition, we examined when the treatments should be applied to the collectors. Results showed that treating twice with 4% hydrated lime, first in early August and again in late August, was successful at mitigating fouling by S. clava  and promoting a set of mussel seed. These treatment times coincide with the main settling period of both starfish and S. clava, which occur in conjunction with water temperatures that promote spawning by these species. The use of acetic acid as a mitigating treatment was effective at controlling macroalgae and S. clava fouling, however it would not be recommended on mussel collectors as it led to high seed mortality. A laboratory trial to determine the effect of 5% acetic acid on juvenile mussels (<1 yr) was conducted following the completion of the field trial. Through allelic frequencies examined by electrophoresis, it was determined that the genetic changes observed after acetic acid treatments could have a potential impact on salinity and temperature tolerance of mussel populations in suspension culture. A possible decrease of phenotypic plasticity of mussel culture by these genetic changes could eventually decrease the productivity of cultured mussels. Nevertheless, more results need to be obtained to confirm this hypothesis.

abstract: Source: Masters Abstracts International, Volume: 45-03, page: 1328.


title: The effect of pertussis toxin on insulin secretion from obese (fa/fa) Zucker rats

contributor: Anend, J.F. (Supervisory Committee Member)

contributor: Donald, A.W. (Supervisory Committee Member)

contributor: Nijjar, M.S. (Supervisory Committee Member)

format: 110 electronic application/pdf

subject: Biology, Animal Physiology

abstract: The obese (fa/fa) Zucker rat is a genetic model of childhood-onset obesity in humans. Pathological changes seen in this rat include, among others, a pronounced hyperinsulinemia in the presence of normoglycemia. The etiology of elevated blood levels of insulin is unknown. These studies investigated the role of the inhibitory guanine nucleotide binding protein G$\sb{\rm i}$ of adenylate cyclase in the endocrine pancreas. The hypothesis was that function of G$\sb{\rm i}$ in obese rats was compromised, resulting in loss of inhibitory pathways. This loss of inhibition could contribute to hypersecretion of insulin.

abstract: To test this hypothesis, two separate sets of experiments were performed. Initially isolated pancreatic islets of lean and obese Zucker rats were used. The second experiment employed an isolated perfused pancreas preparation. The function of inhibitory hormones of insulin secretion reported to act via G$\sb{\rm i}$, including epinephrine, somatostatin and galanin, were tested. Pertussis toxin was used to inactivate G$\sb{\rm i}$ both 'in vivo' and in isolated islets. (Abstract shortened by UMI.).

abstract: Source: Masters Abstracts International, Volume: 30-03, page: 0652.