Development and Application of an Interactive Neuropathology iBook as a Complementary Learning Tool for Veterinary Medicine Students.

Neuropathology is a challenging subject for most medical students. Delivering a gamified learning tool on this topic may motivate students and increase knowledge in the discipline. We report the development of such a tool in iBook format for the systemic pathology course delivered at Ross University School of Veterinary Medicine. Composed of 10 chapters (cases), this Neuropathology iBook (NP-iB) reviews basic clinical manifestations, neuropathology, and pathogenesis of common non-neoplastic conditions that cause brain disease in domestic animals. The goal of each chapter is to reach a diagnosis by interactively answering specific questions after reviewing relevant medical history, clinical pathology, and autopsy findings. Our hypothesis: the NP-iB improves students' ability to recognize these diseases, reflected in higher test scores. Using a post-test only control group design, data were gathered from all students enrolled in the course in two different semesters, fall 2017 and spring 2018 (n = 300). NP-iB users (n = 51, 17%) and usage time were identified by answers to multiple-choice questions embedded in the course assessments. Ninety percent of users had a positive perception although no statistically significant differences were found in median test scores between users and non-users. Statistically significant test score differences were found across how much time students used the NP-iB (p = .005); the lowest test score median values were found for neuropathology questions not related to the NP-iB, in students who used it for more than 3 hours. Unexpectedly, a low number of students preferred this digital learning tool, and its use did not improve their learning outcomes.

Freedom from Tritrichomonas foetus infection in cattle in St. Kitts.

Trichomonosis is an endemic disease in cattle that are reared under extensive conditions and bred by natural mating. It causes profound economic losses to the producers by increasing calving interval, increasing embryo losses, and decreasing pregnancy rates. The aim of this study was to determine whether Tritrichomonas foetus infections were absent from cattle in St. Kitts. Using the modified hypergeometric method, preputial samples from bulls (n = 78) were tested using the InPouch™ culture for presence of T. foetus. Results highlighted an absence of trichomoniasis in bulls on St. Kitts with a 95% confidence.

Using the Virtual World of Second Life in Veterinary Medicine: Student and Faculty Perceptions.

Virtual worlds are emerging technologies that can enhance student learning by encouraging active participation through simulation in immersive environments. At Ross University School of Veterinary Medicine (RUSVM), the virtual world of Second Life was piloted as an educational platform for first-semester students to practice clinical reasoning in a simulated veterinary clinical setting. Under the supervision of one facilitator, four groups of nine students met three times to process a clinical case using Second Life. In addition, three groups of four clinical faculty observed one Second Life meeting. Questionnaires using a 4-point Likert scale (1=strongly disagree to 4=strongly agree) and open-ended questions were used to assess student and clinical faculty perceptions of the Second Life platform. Perception scores of students (M=2.7, SD=0.7) and clinical faculty (M=2.7, SD=0.5) indicate that Second Life provides authentic and realistic learning experiences. In fact, students (M=3.4, SD=0.6) and clinical faculty (M=2.9, SD=1.0) indicate that Second Life should be offered to future students. Moreover, content analyses of open-ended responses from students and faculty support the use of Second Life based on reported advantages indicating that Second Life offers a novel and effective instructional method. Ultimately, results indicate that students and clinical faculty had positive educational experiences using Second Life, suggesting the need for further investigation into its application within the curriculum.

Biofilm formation of hypermucoviscous and non-hypermucoviscous Klebsiella pneumoniae recovered from clinically affected African green monkey (Chlorocebus aethiops sabaeus).

In recent years, an emergent Klebsiella pneumoniae hypermucoviscous (HMV) phenotype has been associated with increased invasiveness and pathogenicity in primates. The HMV phenotype is characterized by different capsular serotypes, associated with several genes including the rmpA (regulator of mucoid phenotype) and magA (mucoviscosity-associated) genes. In African green monkeys (AGM) (Chlorocebus aethiops sabaeus) serotypes K1 and K5 have been implicated in fatal multisystemic abscesses. In order to better understand the epizootiology of this pathogen, the capacity of biofilm production of K. pneumoniae isolates presenting the HMV was compared to non-HMV isolates at three different temperatures (25, 30 and 37 °C). The results indicate that HMV and non-HMV isolates display similar capacity to form biofilms at the three different evaluated temperatures. Temperature appears to play a role in the formation of biofilms by K. pneumoniae presenting the HMV phenotype, where larger biofilms were formed at 37 °C than at 25 °C. Knowledge regarding local environmental sources of K. pneumoniae and the possible role of wildlife in the maintenance of this agent in the area is necessary to develop effective recommendations for the prevention and management of this disease in captive AGM populations.

Patterns and predictors of antimicrobial resistance among Staphylococcus spp. from canine clinical cases presented at a veterinary academic hospital in South Africa.

BACKGROUND: Antimicrobial resistance in staphylococci, often associated with treatment failure, is increasingly reported in veterinary medicine. The aim of this study was to investigate patterns and predictors of antimicrobial resistance among Staphylococcus spp. isolates from canine samples submitted to the bacteriology laboratory at the University of Pretoria academic veterinary hospital between 2007 and 2012. Retrospective data of 334 Staphylococcus isolates were used to calculate the proportion of samples resistant to 15 antimicrobial agents. The Cochran-Armitage trend test was used to investigate temporal trends and logistic regression models were used to investigate predictors of antimicrobial resistance in Staphylococcus aureus and Staphylococcus pseudintermedius. RESULTS: Results show that 98.2% (55/56) of the S. aureus isolates were resistant to at least one drug while 42.9% were multidrug resistant. Seventy-seven percent (214/278) of the S. pseudintermedius isolates were resistant to at least one drug and 25.9% (72/278) were multidrug resistant. Resistance to lincospectin was more common among S. aureus (64.3%) than S. pseudintermedius (38.9%). Similarly, resistance to clindamycin was higher in S. aureus (51.8%) than S. pseudintermedius (31.7%) isolates. There was a significant (p = 0.005) increase in S. aureus resistance to enrofloxacin over the study period. Similarly, S. pseudintermedius exhibited significant increasing temporal trend in resistance to trimethoprim-sulphamethoxazole (p = 0.004), clindamycin (p = 0.022) and orbifloxacin (p = 0.042). However, there was a significant decreasing temporal trend in the proportion of isolates resistant to doxycycline (p = 0.041), tylosin (p = 0.008), kanamycin (p = 0.017) and amoxicillin/clavulanic acid (p = 0.032). CONCLUSIONS: High levels of multidrug resistance and the increasing levels of resistance to sulphonamides, lincosamides and fluoroquinolones among Staphylococcus spp. isolates in this study are concerning. Future studies will need to investigate local drivers of antimicrobial resistance to better guide control efforts to address the problem.

Validation of a Model for Teaching Canine Fundoscopy.

A validated teaching model for canine fundoscopic examination was developed to improve Day One fundoscopy skills while at the same time reducing use of teaching dogs. This novel eye model was created from a hollow plastic ball with a cutout for the pupil, a suspended 20-diopter lens, and paint and paper simulation of relevant eye structures. This eye model was mounted on a wooden stand with canine head landmarks useful in performing fundoscopy. Veterinary educators performed fundoscopy using this model and completed a survey to establish face and content validity. Subsequently, veterinary students were randomly assigned to pre-laboratory training with or without the use of this teaching model. After completion of an ophthalmology laboratory on teaching dogs, student outcome was assessed by measuring students' ability to see a symbol inserted on the simulated retina in the model. Students also completed a survey regarding their experience with the model and the laboratory. Overall, veterinary educators agreed that this eye model was well constructed and useful in teaching good fundoscopic technique. Student performance of fundoscopy was not negatively impacted by the use of the model. This novel canine model shows promise as a teaching and assessment tool for fundoscopy.

Autism spectrum disorders and fetal hypoxia in a population-based cohort: accounting for missing exposures via Estimation-Maximization algorithm.

BACKGROUND: Autism spectrum disorders (ASD) are associated with complications of pregnancy that implicate fetal hypoxia (FH); the excess of ASD in male gender is poorly understood. We tested the hypothesis that risk of ASD is related to fetal hypoxia and investigated whether this effect is greater among males. METHODS: Provincial delivery records (PDR) identified the cohort of all 218,890 singleton live births in the province of Alberta, Canada, between 01-01-98 and 12-31-04. These were followed-up for ASD via ICD-9 diagnostic codes assigned by physician billing until 03-31-08. Maternal and obstetric risk factors, including FH determined from blood tests of acidity (pH), were extracted from PDR. The binary FH status was missing in approximately half of subjects. Assuming that characteristics of mothers and pregnancies would be correlated with FH, we used an Estimation-Maximization algorithm to estimate HF-ASD association, allowing for both missing-at-random (MAR) and specific not-missing-at-random (NMAR) mechanisms. RESULTS: Data indicated that there was excess risk of ASD among males who were hypoxic at birth, not materially affected by adjustment for potential confounding due to birth year and socio-economic status: OR 1.13, 95%CI: 0.96, 1.33 (MAR assumption). Limiting analysis to full-term males, the adjusted OR under specific NMAR assumptions spanned 95%CI of 1.0 to 1.6. CONCLUSION: Our results are consistent with a weak effect of fetal hypoxia on risk of ASD among males. E-M algorithm is an efficient and flexible tool for modeling missing data in the studied setting.

Second WCB claims: who is at risk?

OBJECTIVES: Many workers with one Workers' Compensation Board (WCB) claim make further claims. If the characteristics of the job, initial injury or worker were predictive of an early second claim, interventions at the time of return to work after the first claim might be effective in reducing the burden of work-related injury. This report explores the characteristic of those who make a second claim. METHODS: Records of all Alberta WCB claims from January 1, 1995, to December 31, 2004, for individuals 18 to < 66 years old were reviewed. For each individual's first claim, sex and age of claimant, type of injury, type of accident, occupation, industry, an indicator of company size, and industry claim rate were extracted, as well as the date of any second claim. The likelihood of second claim and mean time to second claim were estimated. Multivariate analyses were performed using Cox regression. RESULTS: 1,047,828 claims were identified from 490,230 individuals. Of these, 49.2% had at least two claims. In the multivariate model a reduced time to second claim was associated with male sex, younger age and some types of injury and accident. Machining trades were at highest risk of early second claim (hazard ratio [HR] 2.54 compared with administration), and of the industry sectors manufacturing was at highest risk (HR 1.37 compared with business, personal and professional services). CONCLUSION: Some caution is needed in interpreting these data as they may be affected by under-reporting and job changes between claims. Nonetheless, they suggest that there remains room for interventions to reduce the considerable differences in risk of a second claim among workers, jobs and industries.

Second Life and Classroom Environments: Comparing Small Group Teaching and Learning in Developing Clinical Reasoning Process Skills.

Medical education and clinical practice support the development of clinical reasoning competency. Traditionally, the process of clinical reasoning is taught through small group discussions in pre-clinical and clinical medical training, and the need exists to explore further teaching and learning approaches that develop clinical reasoning. This study compared teaching and learning the clinical reasoning process through the virtual platform of Second Life (SL) with the traditional classroom setting. Participants were first semester veterinary students; 34 participated virtually through SL, and 41 experienced traditional classroom interactions. Students and one facilitator engaged in three small group meetings to process a clinical case. A seven-item clinical reasoning rubric guided the teaching, learning, and assessment. Clinical reasoning assignments were scored on a grading scale from 0 to 4 with a maximum result of 28. Descriptive statistics for clinical reasoning assignment scores were (m = 14.0; SD = 2.6) and (m = 12.2; SD = 2.6) in SL and classroom interaction, respectively. Results indicated positive associations for all participants between the rubric item score of gathering historical information with (1) gathering physical examination information (p < 0.01) and (2) prioritizing patient's problems (p = 0.003). Additionally, the rubric item score of gathering physical examination information was positively associated with the rubric item score for prioritizing patient's problems (p = 0.02). Specifically for the SL cohort, results demonstrated that rubric item scores were significantly higher for gathering historical information (p = 0.03), gathering physical examination information (p < 0.01), and prioritizing patient's problems (p = 0.02). Small group interaction using SL and traditional classroom environments offers a comparable educational platform for developing clinical reasoning process skills.

Body mass index and childhood asthma: a linear association?

Our objective was to characterize the association between body mass index (BMI) and childhood asthma while adjusting for individual and neighborhood socioeconomic factors. Data were obtained from 3,804 students 10 to 11 years of age in Nova Scotia, Canada. Asthma was defined as parent-reported doctor-diagnosed asthma or bronchitis. Smoothed curves suggested a linear association between BMI and asthma with a 6 % increase in prevalence per unit increase of BMI. This association was independent of allergies, sex, and socioeconomic factors. Girls from socioeconomically disadvantaged neighborhoods were less likely to be asthmatic as were boys from well-educated and wealthy families.

A preliminary investigation into the prognostic relevance of symmetric dimethylarginine in critically ill dogs.

OBJECTIVE: To determine if there is an association between the concentration of symmetric dimethylarginine (SDMA) in dogs measured at the time of admission with the severity of critical illness and short-term mortality. DESIGN: This prospective observational study recruited critically ill dogs with heterogeneous diagnoses and then classified their disease severity using the acute patient physiologic and laboratory evaluation complete score as having either a good (<30) or poor (≥30) prognosis. SETTING: This study was conducted at Ross University Veterinary Clinic between January and November 2015. ANIMALS: After exclusion of dogs diagnosed with acute kidney injury, 22 critically ill dogs and 7 control dogs were included in the study. INTERVENTIONS: Each dog was assigned an acute patient physiologic and laboratory evaluation score calculated by the summation of individual scores allocated to selected clinical, focused assessment by sonography, hematological, and biochemistry results. Plasma SDMA concentrations were measured for all dogs at the time of admission. MEASUREMENT AND MAIN RESULTS: There was no difference identified in SDMA concentrations between dogs with a severe category of disease as compared to mild to moderate category, or critically ill dogs compared to control dogs. There was also no difference identified in SDMA concentrations in survivors as compared to nonsurvivors. Similarly, SDMA concentration was not higher in nonsurvivors than in survivors (P = 0.968). In this population of dogs, SDMA was not a prognostic indicator. CONCLUSION: Further work may be warranted in specific populations of animals but based upon this work SDMA is likely of little relevance.

Burden and predictors of Staphylococcus aureus and S. pseudintermedius infections among dogs presented at an academic veterinary hospital in South Africa (2007-2012).

BACKGROUND: Staphylococci are commensals of the mucosal surface and skin of humans and animals, but have been implicated in infections such as otitis externa, pyoderma, urinary tract infections and post-surgical complications. Laboratory records provide useful information to help investigate these infections. Therefore, the objective of this study was to investigate the burdens of these infections and use multinomial regression to examine the associations between various Staphylococcus infections and demographic and temporal factors among dogs admitted to an academic veterinary hospital in South Africa. METHODS: Records of 1,497 clinical canine samples submitted to the bacteriology laboratory at a veterinary academic hospital between 2007 and 2012 were included in this study. Proportions of staphylococcal positive samples were calculated, and a multinomial logistic regression model was used to identify predictors of staphylococcal infections. RESULTS: Twenty-seven percent of the samples tested positive for Staphylococcus spp. The species of Staphylococcus identified were S. pseudintermedius (19.0%), S. aureus (3.8%), S. epidermidis (0.7%) and S. felis (0.1%). The remaining 2.87% consisted of unspeciated Staphylococcus. Distribution of the species by age of dog showed that S. pseudintermedius was the most common (25.6%) in dogs aged 2-4 years while S. aureus was most frequent (6.3%) in dogs aged 5-6 years. S. pseudintermedius (34.1%) and S. aureus (35.1%) were the most frequently isolated species from skin samples. The results of the multivariable multinomial logistic regression model identified specimen, year and age of the dog as significant predictors of the risk of infection with Staphylococcus. There was a significant temporal increase (RRR = 1.17; 95% CI [1.06-1.29]) in the likelihood of a dog testing positive for S. pseudintermedius compared to testing negative. Dogs ≤ 8 years of age were significantly more likely to test positive for S. aureus than those >8 years of age. Similarly, dogs between 2-8 years of age were significantly more likely to test positive for S. pseudintermedius than those >8 years of age. In addition, dogs 2-4 years of age (RRR = 1.83; 1.09-3.06) were significantly more likely to test positive for S. pseudintermedius compared to those <2 years of age. The risk of infection with S. pseudintermedius or S. aureus was significantly higher in ear canal and skin specimens compared to other specimens. CONCLUSIONS: The findings suggest that S. pseudintermedius and S. aureus were the most commonly isolated species from dogs presented at the study hospital. Age of the dog and the location of infection were significant predictors of infection with both Staphylococcus species investigated. Significant increasing temporal trend was observed for S. pseudintermedius but not S. aureus. This information is useful for guiding clinical decisions as well as future research.

The Effects of Music during a Physical Examination Skills Practice: A Pilot Study.

Some veterinary students experience elevated stress, anxiety, and depression resulting in disease and psychological changes. Elevated arousal, negative moods, and lack of interest can negatively affect performance and learning. Psychoacoustic music promotes calming effects using simple and slow piano sounds and can positively impact well-being and functioning. This pilot study assessed the effects of music on blood pressure, pulse, arousal, and mood during a canine physical examination laboratory. In an AB/BA crossover study, 17 students were randomly allocated to practice physical examination skills while listening to Through a Dog's Ear, Volume 1. Psychological and physiologic data were collected. Nonparametric methods were used to test for significant differences in psychological and physiologic data and a linear mixed models approach was used to test for physiological differences. There were no significant baseline differences between the music and no music groups for DASS-21 depression, anxiety, or stress scores; however, there were significant time differences between pretest and posttest on arousal and mood as measured by the Profile of Mood Sates (POMS) Depression, Fatigue-Inertia, and Tension Anxiety subscales. Linear mixed models revealed no significant treatment effect on the pulse and diastolic blood pressure; however, there was a significant systolic blood pressure treatment effect. Future indications include repeating the study with a larger sample to examine longitudinal psychological and physiological benefits.

Mapping occurrence of Taenia solium taeniosis/cysticercosis and areas at risk of porcine cysticercosis in Central America and the Caribbean basin.

BACKGROUND: This study aimed to map the occurrence of Taenia solium taeniosis/cysticercosis at national level within Central America and the Caribbean basin, and to map the distribution of porcine cysticercosis at first-level administrative subdivision level (department level) and the porcine population at risk. This zoonotic parasite is believed to be widely endemic across most of Latin America. However, there is little information readily available for Central America and the Caribbean basin. Taenia solium has been ranked the most important foodborne parasitic hazard globally and within endemic areas is a common cause of preventable epilepsy. METHODS: We conducted a structured literature search in PubMed, supplemented and crossed-referenced with relevant academic databases, grey literature, and active searches in identified literature, to identify all records of T. solium presence in Central America and the Caribbean basin between 1986 and April 2017. To retrieve grey literature, government entities, researchers and relevant institutions across the region were contacted in an attempt to cover all countries and territories. Identified records containing data on porcine cysticercosis were geo-referenced to identify department level distribution and compared to modelled distributions of pigs reared under extensive production systems. RESULTS: We identified 51 records of T. solium at the national level, covering 13 countries and an additional three countries were included based on World Organisation for Animal Health (OIE) reports, giving a total of 16 countries out of 41 with evidence of the parasite's presence. Screening records for porcine cysticercosis data at the departmental level confirmed porcine cysticercosis presence in 11 departments across six countries (Colombia, Guatemala, Honduras, Mexico, Nicaragua and Venezuela). CONCLUSIONS: When comparing these results to areas where pigs were kept in extensive production systems and areas where no information on porcine cysticercosis exists, it is apparent that porcine cysticercosis is likely to be underreported, and that a substantial part of the regional pig population could be at risk of contracting porcine cysticercosis. More detailed information on the distribution of T. solium and accurate burden estimations are urgently needed to grasp the true extent of this zoonotic parasite and the public health and agricultural problems it potentially poses.

Design and Validation of a Three-Dimensional Printed Flexible Canine Otoscopy Teaching Model.

INTRODUCTION: A teaching model was sought to improve canine otoscopy skill and reduce use of teaching dogs. METHODS: An otoscopy teaching model was printed in a flexible medium on a desktop three-dimensional printer from a magnetic resonance image of a canine external ear canal. The model was mounted in a polyvinyl dog mannequin. Validation of the teaching model was sought from student, faculty, and dog perspective. Student perception of prelaboratory training was assessed using a survey regarding their experience. Otoscopy skill was assessed by faculty grading the ear anatomy visualized as well as the time required to prepare for and perform otoscopy and the time to the dog's first sign of aversion. The time data were used to assess whether there was a reduction in use of teaching dogs. Data from students exposed to the otoscopy model as part of their prelaboratory training (n = 20) were compared with those that were not exposed to the model (n = 19). RESULTS: The students found prelaboratory training with the model significantly more helpful than prelaboratory training without the model in all aspects of otoscopy (P < 0.05). Use of the model did not alter otoscopy skill (structures seen or time taken) or decrease dog use. CONCLUSIONS: The students found the model helpful, but the best that can be said is the model did not negatively impact their otoscopy skill acquisition. Although the outcome of the study did not indicate a reduction in teaching dog use, the model has replaced live dog otoscopy in the institute's teaching program for initial canine otoscopy exposure.

Detection of West Nile Virus and other common equine viruses in three locations from the Leeward Islands, West Indies.

Equines in the West Indies are used for recreational purposes, tourism industry, racing and agriculture or can be found in feral populations. Little is known in the Caribbean basin about the prevalence of some major equine infectious diseases, some with zoonotic potential, listed as reportable by the OIE. Our objective was to study the prevalence of antibodies for West Nile Virus (WNV), Equine Herpes Virus-1 and 4 (EHV-1 and EHV-4), Equine Influenza (EI), Equine Viral Arteritis (EVA) and Equine Infectious Anemia Virus (EIAV) using a retrospective serological convenience study. We used 180 equine serum samples, 140 from horses and 40 from donkeys in St. Kitts, Nevis, and Sint Eustatius, collected between 2006 and 2015 that were tested with ELISA kits and virus neutralization (for WNV and EVA). Combining ELISA with virus neutralization testing, 25 (13.8%) equine sera were WNV positive (a mixture of indigenous and imported equines) and 3 sera (1.6%) showed doubtful results. For EHV-1, 41 equines (23.7%), mean age 6.7 years, were seropositive. For EHV-4, 138 equines were found seropositive (82.8%), mean age 6.3 years. For EI, 49 equines (27.2%), mean age 7.5 years, were seropositive on ELISA, some previously vaccinated horses. No antibodies against EAV were found on virus neutralization testing, although one animal (0.6%), was EAV positive on ELISA. All samples were EIAV negative. The seroprevalence for EHV-1 and EHV-4 is similar to other parts of the world. For the first time in the study location serologic evidence of antibodies against WNV and EI is reported. This was found in both indigenous and imported animals, highlighting the need for developing proper surveillance plans based on complementary methods of virus detection. Further studies will be needed to define the prevalence, rates of transmission, characterize local virus strains, and study their impact on these populations.

Degree of corneal anesthesia after topical application of 0.4% oxybuprocaine ophthalmic solution in normal equids.

Oxybuprocaine hydrochloride ophthalmic solution has been widely used off-label in horses and donkeys, despite lack of data demonstrating efficacy and safety in these species. The objective of this study was to assess anesthetic efficacy of 0.4% oxybuprocaine hydrochloride ophthalmic solution in horses (n = 5) and donkeys (n = 24) and compare the effects with 0.5% proparacaine hydrochloride ophthalmic solution. The baseline corneal touch threshold (CTT) was measured with a Cochet-Bonnet esthesiometer. Donkeys (n = 12) and horses (n = 5) in group A received sterile ophthalmic solutions 0.4% oxybuprocaine with fluorescein (also termed benoxinate with fluorescein, abbreviated as ben + flu) instilled in one eye and 0.9% sterile sodium chloride solution (NaCl) with fluorescein (Na + flu) in the contralateral eye. Donkeys (n = 12) and horses (n = 5) in group B received sterile ophthalmic solutions (ben + flu) in one eye and 0.5% proparacaine with fluorescein (prop + flu) in the contralateral eye. The CTT was measured at 1 and 5 min post-application and at 5-minute intervals until 75 min after treatment. The CTT changes over time differed significantly between oxybuprocaine-treated and control eyes (P < 0.001). The CTT continued to decrease throughout the duration of the study when compared with baseline values. No statistically significant difference in onset, depth, or duration of corneal anesthesia was found between oxybuprocaine and proparacaine treated eyes during the time of the study. Interestingly, horses were shown to have a significantly more sensitive cornea than donkeys (P = 0.002). Oxybuprocaine and proparacaine reduced corneal sensitivity in donkeys and horses. No local irritation was observed with 0.4% oxybuprocaine.

La solution ophtalmique d'hydrochlorure d'oxybuprocaïne a été utilisée extensivement en dérogation chez les chevaux et les ânes, malgré le manque de données démontrant son efficacité et son innocuité chez ces espèces. L'objectif de la présente étude était d'évaluer l'efficacité anesthétique d'une solution ophtalmique d'hydrochlorure d'oxybuprocaïne 0,4 % chez des chevaux (n = 5) et des ânes (n = 24) et comparer les effets avec une solution ophtalmique d'hydochlorure de proparacaïne 0,5 %. La valeur de base du seuil de contact cornéen (SCT) a été mesurée à l'aide d'un esthésiomètre Cochet-Bonnet. Les ânes (n = 12) et chevaux (n = 5) du groupe A ont reçu une solution ophtalmique stérile d'oxybuprocaïne 0,4 % avec de la fluorescéine (également appelée benoxinate avec fluorescéine, abrévié ben + flu) dans un oeil et une solution stérile de chlorure de sodium 0,9 % (NaCl) avec de la fluorescéine (Na + flu) dans l'oeil contra-latéral. Les ânes (n = 12) et chevaux (n = 5) du groupe B ont reçu les solutions ophtalmiques stériles de (ben + flu) dans un oeil et de la propacaïne 0,5 % avec de la fluorescéine (prop + flu) dans l'oeil contra-latéral. Le SCT a été mesuré à 1 et 5 min post-application et à des intervalles de 5 min jusqu'à 75 min après le traitement. Les changements dans le temps du SCT différaient de manière significative entre les yeux traités à l'oxybuprocaïne et les témoins (P < 0,001). Le SCT continua de diminuer tout au long de la durée de l'étude lorsque comparé aux valeurs de base. Aucune différence significative dans le début, la profondeur, ou la durée de l'anesthésie cornéenne ne fut trouvée entre les yeux traités à l'oxybuprocaïne et la proparacaïne durant la durée de l'étude. De manière intéressante, les chevaux avaient une cornée significativement plus sensible que les ânes (P = 0,002). L'oxybuprocaïne et la proparacaïne ont réduit la sensibilité cornéenne chez les ânes et les chevaux. Aucune irritation locale ne fut observée avec l'oxybuprocaïne 0,4 %.(Traduit par Docteur Serge Messier).

The use of an indirect Ostertagia ostertagi ELISA to predict milk production response after anthelmintic treatment in confined and semi-confined dairy herds.

An indirect Ostertagia ostertagi ELISA was used in late lactation milk samples from cows in confined and semi-confined dairy herds to determine if it could predict milk production response after endectocide treatment at calving. Holstein cows from 9 dairy farms from Prince Edward Island (PEI), 5 from central Nova Scotia and 16 from southern Ontario that were participating in a clinical trial of endectocide treatment around calving were used in this study. The cows were randomly treated with either eprinomectin pour-on endectocide or a placebo solution. Milk samples were obtained from cows late in the lactation before treatment was applied. These samples were tested for antibodies to gastrointestinal nematodes (GIN) using the indirect ELISA with the results expressed as optical density ratios (ODR). Production records were obtained from a computerized database of dairy herd improvement data. Pre-calving ODR showed a seasonal pattern. They were higher in the summer and fall and lower during the winter months. Older animals had higher pre-calving ODR values compared with younger cows. Similarly, cows from semi-confined herds had higher parasite antibody levels compared with cows from confined herds. The endectocide treatment did not affect the milk production response in the overall study population. However, the interaction effect between treatment and pre-calving ODR on milk production response after endectocide treatment was significant (P = 0.02), with some evidence of positive treatment response in cows with an ODR > 0.4. The relationship between pre-calving ODR and production response appeared to be quadratic rather than linear.

Evaluation of the stability of Ostertagia ostertagi ELISA microtitre plates over time using cow milk samples.

The objective of this study was to assess the stability of ELISA plates prepared with one of three blocking agents and used with one of two conjugates at various time intervals after preparation of the plates. Two of the blocking agents used were commercially available: one termed stabilgaurd (stab) and one manufactured by SVANOVA Biotek AB Inc. (svan). The third blocking agent used was bovine serum albumin (bsa). A polyclonal rabbit anti-bovine IgG (poly) and an anti-bovine IgG monoclonal (mono) conjugate were used. Eighteen composite individual cow milk samples collected late in lactation (200-400 days in milk) were used in this study. An indirect microtitre plate ELISA that used the Ostertagia ostertagi antigen was used to quantify antibodies against the parasite, present in the milk samples. Each of six blocking agent/conjugate combinations (called systems) were used to test 18 milk sub-samples at 1, 4 and 24 weeks after blocking the plates. Plates blocked with stab and svan were kept at room temperature and an additional set were incubated at 37 degrees C so as to mimic long term storage (about 1 year) and tested only once at 4 weeks. Those blocked with bsa were frozen at -20 degrees C. Concordance correlation coefficients (CCC) and reproducibility were used to assess the agreement between test results conducted on the same milk sample at the various test-times using a particular system. Generally, there was good agreement between tests conducted at different times for all systems. However, the svan-mono and bsa-poly systems had the best agreement with overall CCC values of 96% and 93%, respectively. The svan-poly system had the lowest CCC of 75%. The CCC and reproducibility ranked the systems in a similar way. The high CCC between tests done using plates kept at room temperature and ones incubated at 37 degrees C, suggested that plates would be stable up to a year after blocking. The storage of plates blocked with svan and stab agents under room temperature, makes them more convenient to use and transport relative to bsa-blocked plates that have to be frozen.