Atlantic Veterinary College Research Articles

Training the next generation of veterinarians at the Atlantic Veterinary College

Training the next generation of veterinarians at the Atlantic Veterinary College

Development and validation of main spectral profile for rapid identification of Yersinia ruckeri isolated from Atlantic salmon using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry.

Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) allows rapid and reliable identification of microorganisms. The accuracy of bacterial identification using MALDI-TOF MS depends on main spectral profiles (MSPs) provided in a quality-assured commercial reference library, which requires ongoing improvement. This study aimed to develop and validate an in-house MALDI-TOF MS MSP to rapidly identify Yersinia ruckeri isolated from Atlantic salmon (Salmo salar). The novel MSP was prepared using an isolate of Y. ruckeri recovered from Atlantic salmon and confirmed by 16S rRNA gene sequencing. Subsequently, a validation set which comprises 29 isolates of Y. ruckeri were examined from three fishes: Atlantic salmon (Salmo salar) (n = 26), American eel (Anguilla rostrata) (n = 1), and Atlantic cod (Gadus morhua) (n = 2). These isolates were randomly selected from the Atlantic Veterinary College, Aquatic Diagnostic Services Bacteriology Laboratory's culture collection to validate the novel MSP. Analytical sensitivity of MALDI-TOF MS using the novel MSP to identify the validation set was 86.2%. Repeatability was assessed by acquiring spectra from 30 different spots of a randomly-selected isolate of Y. ruckeri, and analyzed spectra from each spot were compared against the novel MSP. The coefficient of variation was 3.3%. The novel MSP clustered with Bruker MSPs (n = 3) of Y. ruckeri in the reference library and did not falsely identify any closely related bacteria to Y. ruckeri. This study reports the development of a novel MSP of high analytical sensitivity and specificity for rapid identification of Y. ruckeri using MALDI-TOF MS.

Antimicrobial Susceptibility Profiles of Bacteria Commonly Isolated from Farmed Salmonids in Atlantic Canada (2000-2021).

Bacterial infection and antimicrobial resistance are important constraints in the production and sustainability of farmed salmonids. This retrospective study aimed to describe the frequency of bacterial isolates and antimicrobial resistance profiles in salmonid aquaculture in Atlantic Canada. Bacterial isolates and antimicrobial susceptibility testing (AST) results assessed by disk diffusion testing were summarized for 18,776 Atlantic salmon (Salmo salar) and rainbow trout (Oncorhynchus mykiss) samples from 2291 unique cases submitted to the Atlantic Veterinary College, Aquatic Diagnostic Services Bacteriology Laboratory from 2000 to 2021. Kidney was the most commonly submitted tissue (60.29%, n = 11,320), and these specimens were mostly submitted as swabs (63.68%, n = 11,957). The most prevalent pathogens detected in these cases were Yersinia ruckeri type 1 (5.54%, n = 127), Renibacterium salmoninarum (2.10%, n = 48), Aeromonas salmonicida (atypical) (1.66%, n = 38), and Pseudomonas fluorescens (1.22%, n = 28). Most bacterial isolates tested (n = 918) showed resistance to florfenicol, oxytetracycline, ormetoprim-sulfadimethoxine, and trimethoprim-sulfamethoxazole, but not to enrofloxacin. This report provides baseline data for antimicrobial surveillance programs that investigate emerging antimicrobial resistance trends in salmonid aquaculture in Atlantic Canada.

INTEGRATING LEARNING OBJECTIVES IN A MULTI-SEMESTER SUSTAINABLE CONSERVATION DESIGN PROJECT FOR FIRST-YEAR STUDENTS DURING A PANDEMIC

Project selection for first-year design courses can be complicated by the limited skill level of students in their first semester of an engineering program and the scalability required for multiple sections and large classes. Additionally, the project must address the course's learning objectives and provide a sense of authenticity to help students understand the role of engineers in society. Afirst-year design course can be seen by students as the ‘introduction to engineering,’ enabling them to decide whether to pursue engineering as a profession or not. In addition to the already taxing demands imposed on a project for a first-year design course, students at the University of Prince Edward Island completed a design project encompassing two engineering courses andcontributed to a scientific research study on bat conservation. Partnering with researchers in the Atlantic Veterinary College, students designed, built, and installed bat houses equipped with sensors to remotely collect temperature, humidity, and the presence of individual bats within the colony. Constructing 21 bat houses promoted conservation efforts of bats across the province and taught students the critical role of engineers in a sustainable society. This paper presents a discussion on project selection for first-year design courses, how the learning objectiveswere met for two first-year design courses during a pandemic, and describe the community partner's role\ throughout the design project.

Poor performance due to epiglottic retroversion in a Standardbred trotter

SummaryA 3‐year‐old Standardbred trotting gelding presented to the Atlantic Veterinary College for diagnostic work‐up of poor performance and abnormal respiratory noise during exercise. Physical examination was unremarkable, and no significant findings were identified on standing endoscopic examination of the upper respiratory tract. Treadmill endoscopy was utilised for dynamic evaluation of the upper respiratory tract; a diagnosis of epiglottic retroversion was confirmed. The owner requested euthanasia of the gelding, and a post‐mortem evaluation was completed. Despite thorough gross and histological examination of the head and neck on post‐mortem examination, no evidence was identified to support the postulated aetiologies for epiglottic retroversion currently found in the literature. This case represents the first reported findings from a post‐mortem examination of a horse with epiglottic retroversion.

Endoparasites in dogs and cats diagnosed at the Veterinary Teaching Hospital (VTH) of the University of Prince Edward Island between 2000 and 2017. A large-scale retrospective study

Although many studies on the frequency of endoparasites in dogs and cats in Canada have been reported, seasonal and/or annual patterns are often not evaluated. The frequency and risk factors of endoparasite infections from fecal samples of cats and dogs submitted to the Veterinary Teaching Hospital of the Atlantic Veterinary College, University of Prince Edward Island-Canada were determined, using univariable and multivariable logistic regression analyses. Investigated predictors of endoparasitism available in the 2000–2017 database included sex, age, geographic origin and seasonality. A total of 15,016 dogs and 2,391 cats were evaluated for endoparasite status using specific diagnostic tests: direct smear, Baermann, and/or 33 % zinc sulfate solution in a standardized centrifugal flotation method. Overall, twelve and eight parasite genera were detected in dogs and cats, respectively. The overall proportional infection was 14.6 %, and the cat population showed a higher frequency of positivity to parasites compared to the dog population (P < 0.001). The most frequent genera recovered in the whole population (dogs and cats), were Giardia duodenalis (5.2 %), Cystoisospora spp. (3.3 %) and Toxocara spp. (3.2 %). Endoparasitism levels were diagnosed more in feces submitted from young, female intact dogs from PEI compared to the baselines of mature, sterilized male dogs from other provinces, respectively, and diagnoses occurred more often in autumn months than in winter months. There was no significant diagnostic trend across the years for the individual parasites models. The frequency of detected potentially zoonotic parasites in this study highlights the veterinary public health and One Health context of parasitic infections in pets. Although the presented results are not from a random sample and therefore frequency results should be interpreted with caution, the model relationship results may still be relevant. In addition, results are of value to estimate parasite impact and to assist researchers, veterinarians and pet-owners with suitable information to control parasites.

Time Series Regression in Aquaculture

Time Series Regression in Aquaculture

Risk factors for treatment failure in antibiotic treatments against Piscirickettsiosis in farmed Atlantic salmon in Chile

Risk factors for treatment failure in antibiotic treatments against Piscirickettsiosis in farmed Atlantic salmon in Chile

Production and health constraints to sustainable Nile tilapia production by small-holders, using net cages at the Três Marias reservoir, Brazil

Production and health constraints to sustainable Nile tilapia production by small-holders, using net cages at the Três Marias reservoir, Brazil

Cross‐sectional study to investigate the presence of salmon pancreas disease virus in wild and feral fish populations in 10 lakes, Los Lagos Region, Chile

1 Department of Preventive Veterinary Medicine, Faculty of Veterinary Science, University of Chile, Santiago, Chile2 PhD Program in Agriculture, Forestry and Veterinary Science, University of Chile, Santiago, Chile3 Department of Health Management, Atlantic Veterinary College, University of Prince Edward Island,Charlottetown, PEI, Canada

Sea lice monitoring on Atlantic salmon farms in New Brunswick, Canada: comparing audit and farm staff counts

Sea lice audits were performed by the Atlantic Veterinary College on commercial aquaculture sites in New Brunswick, Canada, in 2011. Although the primary objective was to verify that farms were reporting similar lice counts to third-party counts, more detailed comparisons were made to identify when lice counts were more likely to differ between the audit team and farm employees. A total of 28 sea lice audits were conducted on 16 sites between June and December 2011. During each audit, 10 cages were evaluated per site where possible, with ten fish per cage being evaluated by an audit technician and a further ten by a farm employee. Data analysis included descriptive statistics of lice counts by stage and limits of agreement plots. A random effects negative binomial model that accounted for clustering of cages within sites was applied to assess the effect of counter type and season on lice counts by stage. The results indicate that farms counts were generally in agreement with audit counts. However, when the average counts for chalimus and preadult (male and female) and adult male lice stages were high, farm counters were more likely to report a lower value. Higher lice counts were observed during autumn compared to summer especially for the adult female stage. Finally, there was a significant clustering effect for site and cage, with most of the variation attributable to site.

Subcuticular Urate Accumulation in an American Lobster (Homarus americanus)

An unusually "lumpy" lobster, Homarus americanus, was presented to the Atlantic Veterinary College Lobster Science Centre for evaluation. The lobster was weak with numerous pale, raised, and flat areas (diameter, 3-15 mm) on the exoskeleton, some of which were ulcerated. On postmortem examination, the pale areas corresponded to accumulations of viscous to free-flowing white material, which was found in only the subcuticular connective tissues. No internal organs were affected. Direct light examination of nonstained impression smears of the material showed abundant crystals resembling uric acid, amorphous urates, and sodium urate, which were readily soluble in 1 M potassium hydroxide. Wright-Giemsa stained imprints showed numerous fine, rounded, nonstaining granules free in the background and within individual round cells. Fourier-transformed infrared spectroscopy confirmed the presence of urates or mixed urate salts. Hemolymph plasma urea (1.7 mmol/liter) and uric acid (287 μmol/liter) concentrations were slightly higher than those seen with 36-hour emersion. Histologic sections showed aggregates of vacuolated mononuclear cells in the loose subcuticular connective tissue occasionally infiltrating between underlying muscle fibers. Grossly visible urate deposits are occasionally documented in land crabs and rarely reported in the blue crab; none, however, are associated with deformation of the cuticle. Possible etiologies include increased uric acid intake or production or decreased excretion. Anecdotal reports of similarly affected lobsters have been received but are intermittent and undocumented.

Prevalence of Batrachochytrium dendrobatidis in three species of wild frogs on Prince Edward Island, Canada

Chytridiomycosis, caused by the fungus Batrachochytrium dendrobatidis (Bd), has resulted in the decline or extinction of approximately 200 frog species worldwide. It has been reported throughout much of North America, but its presence on Prince Edward Island (PEI), on the eastern coast of Canada, was unknown. To determine the presence and prevalence of Bd on PEI, skin swabs were collected from 115 frogs from 18 separate sites across the province during the summer of 2009. The swabs were tested through single round end-point PCR for the presence of Bd DNA. Thirty-one frogs were positive, including 25/93 (27%) green frogs Lithobates (Rana) clamitans, 5/20 (25%) northern leopard frogs L. (R.) pipiens, and 1/2 (50%) wood frogs L. sylvaticus (formerly R. sylvatica); 12 of the 18 (67%) sites had at least 1 positive frog. The overall prevalence of Bd infection was estimated at 26.9% (7.2-46.7%, 95% CI). Prevalence amongst green frogs and leopard frogs was similar, but green frogs had a stronger PCR signal when compared to leopard frogs, regardless of age (p < 0.001) and body length (p = 0.476). Amongst green frogs, juveniles were more frequently positive than adults (p = 0.001). Green frogs may be the most reliable species to sample when looking for Bd in eastern North America. The 1 wood frog positive for Bd was found dead from chytridiomycosis; none of the other frogs that were positive for Bd by PCR showed any obvious signs of illness. Further monitoring will be required to determine what effect Bd infection has on amphibian population health on PEI.

Cutaneous and Tendon Sheath Mastocytomas with Eosinophilic Joint and Tendon Sheath Effusions in a Horse

Cutaneous and Tendon Sheath Mastocytomas with Eosinophilic Joint and Tendon Sheath Effusions in a Horse

Babesia (Theileria) annae in a Red Fox (Vulpes vulpes) from Prince Edward Island, Canada

A 4-6-mo-old female red fox (Vulpes vulpes) was presented to the Atlantic Veterinary College (AVC) Teaching Hospital, Prince Edward Island, Canada. On presentation, the fox was weak and had pale mucous membranes. A complete blood count and a serum biochemistry profile were performed. Blood smear examination revealed low numbers of erythrocytes containing centrally to paracentrally located, single, rarely multiple, approximately 1 x 2 microm, oval to round organisms with morphology similar to Babesia microti. Polymerase chain reaction testing and DNA sequencing of the Babesia species 18S rRNA gene were performed on DNA extracted from whole blood. Results were positive for a Babesia microti-like parasite genetically identical to Babesia (Theileria) annae. The fox was euthanized due to poor prognosis for recovery. Necropsy examination revealed multifocal to locally extensive subacute nonsuppurative meningoencephalitis, an eosinophilic broncho-pneumonia, a moderate diffuse vacuolar hepatopathy, and lesions associated with blunt trauma to the left abdominal region. This is the first reported case of a red fox in Canada infected with a piroplasm. It remains uncertain whether the presence of this hemoparasite in this fox was pathogenic or an incidental finding. The potential for competent vectors of Babesia species on Prince Edward Island, the potential for this Babesia microti-like parasite to infect other wild and domestic canids, and the significance of this parasite to the health of infected individuals are yet to be determined.

Identification of the genes encoding for putative gamma aminobutyric acid (GABA) and glutamate‐gated chloride channel (GluCl) alpha receptor subunits in sea lice (Lepeophtheirus salmonis)

Journal of Veterinary Pharmacology and TherapeuticsVolume 30, Issue 2 p. 163-167 Identification of the genes encoding for putative gamma aminobutyric acid (GABA) and glutamate-gated chloride channel (GluCl) alpha receptor subunits in sea lice (Lepeophtheirus salmonis) N. D. TRIBBLE, N. D. TRIBBLE Departments of Biomedical SciencesSearch for more papers by this authorJ. F. BURKA, J. F. BURKA Departments of Biomedical SciencesSearch for more papers by this authorF. S. B. KIBENGE, F. S. B. KIBENGE Pathology and Microbiology, Atlantic Veterinary College, University of Prince Edward Island, Charlottetown, PE, CanadaSearch for more papers by this author N. D. TRIBBLE, N. D. TRIBBLE Departments of Biomedical SciencesSearch for more papers by this authorJ. F. BURKA, J. F. BURKA Departments of Biomedical SciencesSearch for more papers by this authorF. S. B. KIBENGE, F. S. B. KIBENGE Pathology and Microbiology, Atlantic Veterinary College, University of Prince Edward Island, Charlottetown, PE, CanadaSearch for more papers by this author First published: 06 March 2007 https://doi.org/10.1111/j.1365-2885.2007.00823.xCitations: 8 Nicholas Tribble, Department of Biomedical Sciences, Atlantic Veterinary College, 550 University Avenue, Charlottetown, PE, C1A 4P3, Canada. E-mail: [email protected] Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat Citing Literature Volume30, Issue2April 2007Pages 163-167 RelatedInformation

Apparent pseudohyperkalemia in a Chinese Shar Pei dog

Whole blood in a serum clot tube and EDTA-anticoagulated samples from an 8-year-old spayed female Chinese Shar Pei dog were submitted by an external clinic to the diagnostic laboratory at Atlantic Veterinary College for routine biochemical and hematologic analysis prior to entropion surgery. Laboratory abnormalities included mild hyperkalemia (6.3 mmol/L, reference interval 3.6-6.0 mmol/L), mild normocytic, hypochromic, nonregenerative anemia (HCT 0.31 L/L, reference interval 0.37-0.55 L/L; MCHC 290 g/L, reference interval 320-360 g/L), and increased red cell distribution width (RDW; 26.2%, reference interval 11-14%). A small subpopulation of macrocytic, slightly hypochromic erythrocytes was noted on Wright's-Giemsa-stained blood smears. Biochemical and hematologic data obtained from this patient over the previous 7.5 years indicated that serum (and in 1 case, heparinized plasma) potassium concentration was increased (range, 6.3-10.9 mmol/L) in 5 of 8 samples (HCT ranged from 0.31-0.43 L/L, Hgb 91-124 g/L, MCHC 280-312 g/L, and RDW 18.2-26.9%). Clinical signs suggestive of hyperkalemia were not observed at any time, suggesting pseudohyperkalemia as the cause of the increased potassium concentrations. An erythrocyte lysate prepared from a heparinized blood sample had a high potassium concentration (16.8 mmol/L) compared with that of a clinically healthy, non-Shiba control dog (6.7 mmol/L). An osmotic fragility test of the patient's erythrocytes showed 50% hemolysis at 0.57% NaCl, compared with 0.48% NaCl for the control dog, indicating increased fragility. On scanning electron microscopy, a small subpopulation of erythrocytes were large, flattened, and had a tendency to fold. These findings supported the provisional diagnosis of pseudohyperkalemia due to increased intracellular RBC potassium concentration. High-potassium erythrocytes have been reported in Akitas, Shibas, Jindos, other East Asian dog breeds, and occasionally, in mixed-breed dogs. Pseudohyperkalemia should also be considered when an otherwise unexplained elevation in serum or plasma potassium concentration is observed in Chinese Shar Pei dogs, and may be accompanied by increased RDW, low MCHC, and increased osmotic fragility with or without mild anemia.

Pets, Professors, and Politicians: The Founding and Early Years of the Atlantic Veterinary College (review)

Pets, Professors, and Politicians: The Founding and Early Years of the Atlantic Veterinary College (review)

Marian Bruce. Pets, Professors, and Politicians: The Founding and Early Years of the Atlantic Veterinary College.

Marian Bruce. Pets, Professors, and Politicians: The Founding and Early Years of the Atlantic Veterinary College.

The effect of energetic condition on growth dynamics and health of Atlantic cod (Gadus morhua)

Aquatic Diagnostic Services, Atlantic Veterinary College,University of PEI, Charlottetown, Prince Edward Island, CanadaSummaryProlonged starvation resulting in sublethal condition factorvalues was hypothesized to have a detrimental effect on short-termgrowthcapacityuponrefeeding.Cod(Gadusmorhua)werefood-deprived and their length and mass measured beforerefeeding and after 3, 6, 9 and 12 weeks of ad libitum feeding.Total mass increase during the first 3 weeks of feeding wasgreatestinfishwithahigherinitialconditionfactor.Thereversesituation was observed during the last 3 weeks of feeding.Specificgrowthratepeakedintheperiodfromweek4toweek6,exceptincodwiththehighestconditionfactorforwhichasteadydecline in specific growth rate was observed, and was notinfluenced by the condition factor at the start of the feedingperiod. Total mass increase over 12 weeks was also notinfluenced by initial condition factor. Thus by the end of theexperiment, condition factors were lowest in fish with initiallylowcondition factors. The hepatosomatic indexandgonadoso-matic index did not differ at the end of the experiment, but theproportion of mature cod increased with increasing initialcondition factor. A disease outbreak caused significant mortal-ities among fish shortly after the start of the feeding period.Forty-one percent of the fish had died after 84 days. Nomortality was observed among fish that had started theexperiment with the highest condition factor. Mortality wasinversely related to initial condition factor. Growth was exam-ined for survivors exclusively. Poor condition in wild fish mayincreasevulnerabilitytodiseasesandcompensatorygrowthmaynot allow cod with low condition factors to fully recover unlessfood availability remains high over a long period of time.IntroductionWhen refed after a period of slow or negative growth caused bymoderate or severe starvation, fish will restore their energyreserves.Theymayexhibitashortperiodofexceptionallyfastergrowth known as compensatory or catch-up growth by whichfood-deprived fish will reach the size of continuously fedconspecifics. During early life stages food-deprived fish mayeven grow to larger sizes than continuously fed fish (Haywardet al.,1997;HaywardandWang,2001).Catch-upgrowthiswelldocumented in fishes, particularly in freshwater species andsalmonids, including Atlantic salmon Salmo salar (Nicieza andMetcalfe, 1997), rainbow trout Oncorhynchus mykiss (Dobsonand Holmes, 1984), andarctic charr Salvelinus alpinus (Miglavsand Jobling, 1989). Previous studies on catch-up growth havefocused on its impacts on life-history strategies (Nicieza andMetcalfe, 1997) and feeding hierarchies (Jobling and Koskela,1996) as well as on the underlying physiological processes(Be´langer et al., 2002). Hayward et al. (1997) examined com-pensatory growth in view of determining whether restrictedrations elicited hyperphagia and could be used advantageouslyto increase production in aquaculture facilities by using anoptimal feeding regime which would bank on catch-up growthmechanisms. In most studies, short periods of food deprivationwere considered, from a few days to 1 or 2 weeks (Dobson andHolmes, 1984; Ali and Wootton, 2001; Zhu et al., 2001, 2003),butothersusedperiodsaslongas100–120 days(Haywardet al.,1997; Hayward and Wang, 2001).Wild fish may experience prolonged periods of food-deprivation. For instance, Atlantic cod (Gadus morhua) ceasefeeding for as much as 70 days during prespawning and muchof the spawning period (Fordham and Trippel, 1999). Theyalso have to cope with periodic food shortages, particularly inwinter (Dutil et al., 2003). When shortages occur, cod mustdraw energy from body reserves accumulated during periodswhen food was available (Black and Love, 1986; Lambert andDutil, 1997b). As a result, cod exhibit marked seasonal andannual variations in energy reserves (Lambert and Dutil,1997a; Schwalme and Chouinard, 1999), and growth rate(Chouinard and Fre´chet, 1994; Dutil et al., 1999), with fastergrowth occurring in summer and autumn and peak somaticcondition factors being reached in autumn. These variationsare particularly pronounced in cold water stocks (Dutil et al.,1999; Dutil and Brander, 2003). Low condition factors reachedfollowing a prolonged period of fasting are expected topromote catch-up growth when food becomes more abundant.The success of the cod growout industry in eastern Canadamay build on this increased capacity for growth in post-spawning cod caught inshore in early summer; cod more thandouble their body weight in 4–6 months when provided with anearly unlimited source of raw wild mackerel and capelin(Murphy, 2002). On the other hand, metabolic capacities aredepressed and some tissues are significantly atrophied follow-ing an extended period of starvation (Dutil et al., 1998;Be´langer et al., 2002; Marti´nez et al., 2003) which maypotentially impair catch-up growth in more emaciated indi-viduals. Few studies have considered long periods of fooddeprivation in catch-up growth studies (Weatherley and Gill,1981; Pedersen and Jobling, 1989; Paul et al., 1995) and nonehas examined whether poor condition affected the time courseof catch-up growth upon refeeding.The present study assesses whether poor condition resultingfrom prolonged food deprivation may prevent catch-upgrowth to occur. Prolonged starvation resulting in sublethal