IIB or not IIB, part 2: assessing inter-rater and intra-rater repeatability of the Kenney-Doig scale in equine endometrial biopsy evaluation.

Inter- and intra-rater variability negatively affects the reliability of various histopathology grading scales used as prognostic aids in human and veterinary medicine. The Kenney-Doig categorization (grading) scale, which is used to associate equine endometrial histologic lesions with prognostic estimation of a broodmare's reproductive potential, has not been evaluated for inter- or intra-rater variability, to our knowledge. To assess whether the Kenney-Doig system produces reliable results among observers, 8 pathologists, all with American College of Veterinary Pathologists certification, were recruited to blindly categorize the same set of 63 digital equine endometrial biopsy slides as well as to re-evaluate anonymously 21 of 63 of these slides at a later time. Cohen kappa values for pairwise comparison of final Kenney-Doig categories were -0.05 to 0.46 (unweighted) and 0.08-0.64 (weighted), with an average Light kappa of 0.19 (unweighted) and 0.36 (weighted) across all 8 pathologists, 0.14 (unweighted) and 0.33 (weighted) for pathologists at different institutions, and 0.22 (unweighted) and 0.46 (weighted) for pathologists at the same institution. Intra-class correlations measuring intra-rater agreement were 0.12-0.77 with an average of 0.55 for all 8 pathologists. We found that only slight-to-moderate inter-rater agreement and poor-to-good intra-rater agreement was produced by 8 pathologists using the Kenney-Doig scale, suggesting that the system is subject to significant observer variability and care should be taken when communicating Kenney-Doig categories to submitting clinicians with emphasis on the quality of endometrial lesions present instead of the category and associated expected foaling rate.

IIB or not IIB, part 1: retrospective evaluation of Kenney-Doig categorization of equine endometrial biopsies at a veterinary diagnostic laboratory and comparison with published reports.

The Kenney-Doig scale is a histopathology categorization (grading) system often used as the standard for assessing endometrial disease and communicating prognostic fertility information for equine breeding prospects. We investigated how Kenney-Doig categories compared within the same institution and across different institutions to determine if observer variability may contribute to category frequencies. We conducted a retrospective analysis of all equine endometrial submission records between 1998 and 2018 at the Western College of Veterinary Medicine (WCVM) and Prairie Diagnostic Services (PDS). Of 726 biopsies, we found the following category distribution: 46 of 726 (6.3%) I, 307 of 726 (42.3%) IIA, 326 of 726 (44.9%) IIB, and 47 of 726 (6.5%) III. We also conducted a review of the literature and included 6 studies reporting Kenney-Doig category distributions. Chi-square analysis showed significant differences between the category distribution found at WCVM and PDS and the category distribution reported in the 6 studies. To account for differences in mare populations, individual category distributions were generated for 5 pathologists at the WCVM and PDS. The Fisher exact test among these 5 Kenney-Doig categories revealed significant differences in category tendencies, suggesting that observer variation affects the use of the scale. Our results suggest that there is a need for prospective inter-rater and intra-rater agreement studies of the repeatability of the Kenney-Doig scale.

Prevalence and Prognostic Impact of Equus caballus Papillomavirus Type 2 Infection in Equine Squamous Cell Carcinomas in Western Canadian Horses.

Equus caballus papillomavirus type-2 (EcPV-2) has been proposed as a causal factor in equine genital squamous cell carcinoma (SCC). This study had 2 objectives: first, calculate the frequency of papillomavirus (PV) and EcPV-2 infection in papillomas, carcinomas in situ (CIS), and SCCs in Western Canadian horses; and second, determine if EcPV-2 status of equine SCCs is associated with overall survival (OS). EcPV-2 status of 115 archived tissue samples, spanning 6 years, was determined using broad spectrum (MY09/11) and EcPV-2-specific polymerase chain reaction (PCR) assays, EcPV-2-E6/E7 chromogenic RNA in situ hybridization (R-ISH), and amplicon sequencing. A retrospective survey gathered data on history, outcome, breeding, treatment, and rationales of referring veterinarians when managing PV-associated diseases. Histologic grade and completeness of surgical margins of SCCs were also considered. EcPV-2 DNA was identified in 10/58 (17%) SCC, 8/27 (30%) papillomas, 0/5 CIS, and 0/11 lesions identified as "other." Overall, 18/101 (18%) of these lesions were positive for EcPV-2. EcPV-2 was identified in 10/35 (29%) SCCs arising from genital tissues but in 0/22 SCCs from other locations. There was no association between breeding history and EcPV-2 status of genital SCCs. EcPV-2 status of genital SCCs was not associated with OS (P = .76). The strongest negative predictors of OS were a lack of treatment (P < .01) and recurrence post-treatment (P < .01). Weaker predictors of OS included older age at time of diagnosis (P = .02). Completeness of margins at surgical excision, concurrent disease, treatment type, anatomic location of the SCC (anogenital vs other), and histologic grade of the SCC did not influence OS (P > .1).

In Vitro Effects of Pesticides on European Foulbrood in Honeybee Larvae.

Neonicotinoid and fungicide exposure has been linked to immunosuppression and increased susceptibility to disease in honeybees (Apis mellifera). European foulbrood, caused by the bacterium Melissococcus plutonius, is a disease of honeybee larvae which causes economic hardship for commercial beekeepers, in particular those whose colonies pollinate blueberries. We report for the first time in Canada, an atypical variant of M. plutonius isolated from a blueberry-pollinating colony. With this isolate, we used an in vitro larval infection system to study the effects of pesticide exposure on the development of European foulbrood disease. Pesticide doses tested were excessive (thiamethoxam and pyrimethanil) or maximal field-relevant (propiconazole and boscalid). We found that chronic exposure to the combination of thiamethoxam and propiconazole significantly decreased the survival of larvae infected with M. plutonius, while larvae chronically exposed to thiamethoxam and/or boscalid or pyrimethanil did not experience significant increases in mortality from M. plutonius infection in vitro. Based on these results, individual, calculated field-realistic residues of thiamethoxam and/or boscalid or pyrimethanil are unlikely to increase mortality from European foulbrood disease in honeybee worker brood, while the effects of field-relevant exposure to thiamethoxam and propiconazole on larval mortality from European foulbrood warrant further study.

Bayesian Hierarchical Models as Tools to Evaluate the Association Between Groundwater Quality and the Occurrence of Type 2 Diabetes in Rural Saskatchewan, Canada.

There is growing interest in the role of environmental exposures in the development of diabetes. Previous studies in rural Saskatchewan have raised concerns over drinking water contaminants, including arsenic, which has been identified as a possible risk factor for diabetes. Using administrative health and water-quality surveillance data from rural Saskatchewan, an ecological study design was used to investigate associations between concentrations of arsenic, water health standards and aesthetic objectives, and the incidence and prevalence of diabetes. Mixtures of contaminants measured as health standards or as aesthetic objectives were summarized using principal component (PC) analysis. Associations were modeled using Bayesian hierarchical models incorporating both spatial and unstructured random effects, standardized for age and sex, and adjusted for socioeconomic factors and a surrogate measure for smoking rates. Arsenic was not associated with an increased risk of diabetes. For private wells, having groundwater arsenic concentrations in the highest quintile was associated with decreased cumulative diabetes incidence for 2010-2012 (risk ratio [RR] = 0.854, 95% credible interval [CrI] 0.761-0.958) compared with the lowest quintile, a result inconsistent with other studies. For public water supplies, having a first PC score for health standards (primarily summarized selenium, nitrate, and lead) in the third quintile (RR = 1.101, 95% CrI 1.019-1.188), fourth quintile (RR = 1.088, 95% CrI 1.003-1.180), or fifth quintile (RR = 1.115, 95% CrI 1.026-1.213) was associated with an increase in 2010 diabetes prevalence compared with the first quintile. An increase in the PC scores for the third aesthetic objective in private wells (characterized primarily by iron and manganese) was associated with decreased diabetes incidence, although a meaningful dose-response relationship was not evident. No other associations between PC scores for health standards or aesthetic objectives from public or private water supplies and diabetes were identified.

Ecological analysis of associations between groundwater quality and hypertension and cardiovascular disease in rural Saskatchewan, Canada using Bayesian hierarchical models and administrative health data.

Associations between groundwater quality and the prevalence of hypertension and ischemic heart disease were investigated in rural areas of the Canadian province of Saskatchewan. The partially ecological study was analyzed using Bayesian hierarchical models to account for spatial variability in risk. Exposure measures and health outcomes were estimated based on previously collected water quality surveillance data from public water supplies and private wells and administrative health data. Water quality exposures for each study region were estimated by applying geostatistical techniques to arsenic concentrations and principal component (PC) scores. The PC scores summarized groups of parameters measuring either health standards or aesthetic objectives described by the province. Generalized linear mixed models with a log link assessed associations between water quality and observed count of health outcomes relative to the expected value. The Bayesian models contained uncorrelated and spatially correlated random effects for each geographic region. Effect estimates were controlled for sex and age by stratification of case and expected case counts, for smoking by inclusion of sex- and age-specific prevalence of chronic obstructive pulmonary disease as a surrogate covariate, and for education and income by use of census data. There was no evidence for associations between groundwater arsenic concentrations in public or private water supplies and increased risk of hypertension or cardiovascular disease. An increase in the second aesthetic objectives PC score from public supplies was associated with a protective effect against ischemic heart disease. This PC value summarized hardness and magnesium Similarly, an increase in the second aesthetic objectives PC in private supplies was associated with decreased prevalence of hypertension. The results of this study are consistent with others demonstrating a relationship between elevated hardness and magnesium concentrations in drinking water and reduced risk of hypertension and cardiovascular disease. Further investigation is warranted with individual exposure history, particularly with respect to the potential beneficial effect of hard water on the prevalence of hypertension and cardiovascular disease.

Observations of mortality in farmed bison in the Canadian prairies: 2103 - 2016.

The present study is a continuation of a previous mortality study on Saskatchewan bison farms with special emphasis on Malignant Catarrhal Fever. The updated objective of the study was to estimate the most common causes of mortality in farmed bison herds in Western Canada. Results were compared to the previous Saskatchewan study to assess the similarities and differences in the etiology associated with farmed bison deaths across the Prairie Provinces of Canada. The most common cause of death was respiratory disease associated with Mycoplasma bovis, although this was restricted to Alberta and Saskatchewan farm locations. This was in contrast to the previous Saskatchewan based study which did not identify any deaths involving this pathogen. An updated overall assessment of the risks of Malignant Catarrhal Fever in farmed bison at various proximities to sheep operations further confirmed the low risk of occurrence on farms within a 1 km boundary fence distance.

Does antimicrobial therapy improve outcomes in horses with severe equine asthma and a positive tracheal wash bacterial culture?

The objective of this study was to observe the outcomes of adding an antimicrobial treatment to a conventional treatment regime in horses with severe equine asthma in a clinical setting. Eleven client-owned horses with a history consistent with severe equine asthma, increased respiratory effort and nostril flaring, ≥ 20% neutrophils on bronchoalveolar lavage (BAL), and a positive tracheal wash (TW) bacterial culture were treated with environmental management, corticosteroids, and bronchodilators. Six horses were also treated with an antimicrobial (principal group), while the other 5 were administered saline as a placebo (control group). Treatment with antimicrobials significantly improved the post-treatment clinical score of the principal group compared with the pre-treatment score, whereas no significant difference occurred in the control group. The principal group also had significantly less neutrophil myeloperoxidase (MPO) activity post-treatment than pre-treatment, with a median difference of -0.39 units/[protein] in the principal group and a median difference of -0.21 units/[protein] in the controls. There was no difference in MPO activity pre- versus post-treatment in the control group. No differences were noted in the intra-group comparisons of pre- versus post-treatment BAL neutrophil counts, mucus scores, and concentrations of interleukin-8 (IL-8) or tumor necrosis factor-alpha (TNF-α) in bronchoalveolar lavage fluid (BALF) in either group. There were no differences found in the inter-group comparisons of the principal versus controls for each of the pre- and post-treatment time periods for BAL neutrophil count, mucus score, clinical scores, MPO activity, and IL-8 or TNF-α concentrations. The role of airway bacteria in horses with severe equine asthma requires further investigation as antimicrobial therapy improved post-treatment clinical scores and decreased MPO activity in the group of horses studied, but did not affect other measures of airway inflammation.

L'objectif de la présente étude était d'observer dans un contexte clinique les résultats de l'ajout d'un traitement antimicrobien au traitement conventionnel de chevaux souffrant d'asthme sévère. Onze chevaux appartenant à des propriétaires et ayant une histoire correspondant avec de l'asthme sévère, un effort inspiratoire augmenté et un élargissement des narines, ≥ 20 % de neutrophiles dans le lavage bronchoalvéolaire (LBA), et une culture bactérienne positive à partir du lavage trachéal (LT) ont été traités par gestion de leur environnement, des corticostéroïdes, et des broncho-dilatateurs. Six chevaux ont également été traités avec un antimicrobien (groupe principal) alors que les cinq autres chevaux ont reçu de la saline à titre de placebo (groupe témoin). Le traitement avec les antimicrobiens améliora de manière significative le score clinique post-traitement du groupe principal comparativement au score pré-traitement, alors qu'aucune différence significative ne fut notée dans le groupe témoin. Dans le groupe principal on nota également qu'il y avait significativement moins d'activité myéloperoxydase (MPO) des neutrophiles post-traitement comparativement à pré-traitement, avec une différence médiane de −0,39 unités/[protéine] dans le groupe principal et une différence médiane de −0,21 unités/[protéine] dans le groupe témoin. Il n'y avait pas de différence de l'activité MPO pré- versus post-traitement dans le groupe témoin. Aucune différence ne fut notée dans les comparaisons intra-groupe pré- versus posttraitement du dénombrement de neutrophiles dans les LAB, du score de mucus, et des concentrations d'interleukine-8 (IL-8) ou du facteuralpha nécrosant des tumeurs (TNF-α) dans les liquides de lavage broncho-alvéolaire (LLBA) d'un groupe ou l'autre. Aucune différence ne fut trouvée dans les comparaisons inter-groupes du principal versus les témoins pour chacune des périodes de temps pré- et post-traitement pour le dénombrement des neutrophiles des LAB, le score de mucus, les scores cliniques, l'activité MPO, et les concentrations d'IL-8 ou de TNF-α. Le rôle des bactéries dans les voies respiratoires des chevaux souffrant d'asthme sévère nécessite des études supplémentaires étant donné que les thérapies antimicrobiennes ont améliorés les scores cliniques post-traitement et ont diminué l'activité MPO dans le groupe de chevaux étudiés, mais n'affecta pas d'autres mesures de l'inflammation des voies respiratoires.(Traduit par Docteur Serge Messier).

Evaluation of Dogs with Border Collie Collapse, Including Response to Two Standardized Strenuous Exercise Protocols.

Clinical and metabolic variables were evaluated in 13 dogs with border collie collapse (BCC) before, during, and following completion of standardized strenuous exercise protocols. Six dogs participated in a ball-retrieving protocol, and seven dogs participated in a sheep-herding protocol. Findings were compared with 16 normal border collies participating in the same exercise protocols (11 retrieving, five herding). Twelve dogs with BCC developed abnormal mentation and/or an abnormal gait during evaluation. All dogs had post-exercise elevations in rectal temperature, pulse rate, arterial blood pH, PaO2, and lactate, and decreased PaCO2 and bicarbonate, as expected with strenuous exercise, but there were no significant differences between BCC dogs and normal dogs. Electrocardiography demonstrated sinus tachycardia in all dogs following exercise. Needle electromyography was normal, and evaluation of muscle biopsy cryosections using a standard panel of histochemical stains and reactions did not reveal a reason for collapse in 10 dogs with BCC in which these tests were performed. Genetic testing excluded the dynamin-1 related exercise-induced collapse mutation and the V547A malignant hyperthermia mutation as the cause of BCC. Common reasons for exercise intolerance were eliminated. Although a genetic basis is suspected, the cause of collapse in BCC was not determined.

An observational study of mortality on bison farms in Saskatchewan with special emphasis on malignant catarrhal fever.

In December 2011, the Malignant Catarrhal Fever (MCF) Task Force in Saskatchewan recommended that research be conducted on the relationship between the proximity of bison and sheep under typical commercial production settings and bison deaths due to MCF. The objective of this study was to evaluate all causes of death in bison herds and compare the incidence of MCF in herds at varying distances of exposure from sheep operations. Necropsies were completed on 76 of 133 bison reported to have died during the 18-month study period. A total of 7 MCF deaths was reported from 2 large herds within 1.0 km of sheep operations. Although there was a greater risk of MCF deaths in bison herds within 1.0 km of sheep operations than in herds more than 1.0 km away, the overall incidence of MCF deaths within the study period was very low. Most deaths were attributed to non-infectious causes, including copper deficiency.

Étude observationnelle de la mortalité dans des fermes de bisons en Saskatchewan, avec une emphase particulière sur la fièvre catarrhale maligne des bovins. En décembre 2011, le groupe de travail de la Saskatchewan sur la fièvre catarrhale maligne des bovins (FCM) a recommandé la réalisation de travaux de recherche pour étudier le lien entre la proximité des bisons et des moutons dans des milieux de production commerciaux typiques et la mortalité des bisons attribuable à la FCM. La recherche avait pour but d'évaluer toutes les causes de mortalité dans les troupeaux de bisons, puis de comparer l'incidence de la FCM dans les troupeaux à diverses distances d'exposition des exploitations d'élevage de moutons. Des nécropsies ont été réalisées sur 76 des 133 bisons dont la mort a été signalée durant la période d'étude de 18 mois. Un total de sept morts causées par la FCM a été signalé dans deux grands troupeaux situés à une distance de moins de 1 km. Le risque de mortalité pour cause de FCM était supérieur dans les troupeaux de bisons situés à moins de 1 km des exploitations de moutons que dans les troupeaux situés à une distance de plus de 1 km. Cependant, l'incidence totale de mortalité causée par la FCM était très faible. La plupart des mortalités étaient attribuables à des causes non infectieuses, y compris une carence en cuivre.(Traduit par Isabelle Vallières).

Effects of a standardized anesthetic protocol on hematologic variables in healthy cats.

This study evaluated the effects of an anesthetic protocol using intravenous ketamine and midazolam, and intramuscular buprenorphine on hematologic variables in cats. Twelve healthy adult cats had blood collected for a complete blood count before and after the induction of anesthesia. There were significant decreases in red blood cell counts, hemoglobin concentrations and hematocrits after the induction of anesthesia. On average, red blood cell counts and hematocrits decreased by 25%, and hemoglobin concentrations decreased by 24%. Based on hematocrit, 3/12 samples (25%) taken while the cats were anesthetized would have been interpreted as belonging to anemic patients while none of the cats would have been considered anemic before anesthesia. This study suggests that a complete blood count performed on blood taken under anesthesia with this anesthetic protocol should be interpreted cautiously in order to not make a false diagnosis of anemia.