Search

To investigate the agreement between available serologic tests for the detection of antibodies against Anaplasma phagocytophilum and Borrelia burgdorferi, 50 serum samples from horses of unknown clinical status and at low risk for infection were tested. In addition to a point-of-care enzyme-linked immunosorbent assay (pocELISA), the evaluated tests included 2 indirect fluorescent antibody tests (IFATs) for antibodies against A. phagocytophilum and an IFAT, an ELISA confirmed with Western blot, and the Lyme multiplex assay for antibodies against B. burgdorferi. For each pair-wise comparison between serologic tests, the difference in the proportion of seropositive results as well as kappa and the prevalence-adjusted, bias-adjusted kappa were calculated. The proportion of seropositive results differed significantly in each pairwise comparison of tests for detection of antibodies against A. phagocytophilum, and between the pocELISA and IFAT as well as between the pocELISA and Lyme multiplex assay for detection of antibodies against B. burgdorferi. Agreement based on kappa varied from poor to fair while agreement was improved when evaluating prevalence-adjusted, bias-adjusted kappa. Lack of agreement may be explained by differences in methodology between the evaluated tests, cross-reactivity or false-positive and false-negative tests. In addition to the limitations of serologic test interpretation in the absence of clinical disease, this data suggest that screening of horses for exposure to tick-borne diseases in nonendemic areas may not be warranted. [ABSTRACT FROM AUTHOR]

The article discusses a study that was conducted to estimate the seroprevalence of equine granulocytic anaplasmosis (EGA) and equine lyme borreliosis (LB) in Canada using the point-of-care SNAP 4Dx ELISA. The study analyzed a small number of reported cases of EGA and LB in horses in Canada. It concludes with the need for evaluation of serologic tests to understand disease exposure.

Abstract: Fortification of plants with selenium (Se) has been used to increase the Se intake of humans and farm animals but its use for correction of Se deficiency in horses has received little attention. The aims of this study were to evaluate the effect of Se-enriched fertilizer application on the Se concentration of fresh forage and hay, and to test the effect of feeding Se-enriched hay on the Se status of horses fed a basal diet containing inadequate Se (<0.1mg/kg dry matter (DM)). This method of Se supplementation was further compared to a more conventional method, access to Se-containing trace mineral blocks. Application of Se-enriched fertilizer resulted in fresh forage and hay with higher Se content when compared to untreated fresh forage and hay from the same fields. As a result of soil treatment, the concentration of Se in fresh forage and hay was increased from concentrations considered inadequate to concentrations considered adequate for meeting the dietary requirements for horses. Both feeding of Se-enriched hay and access to the Se-containing trace mineral block increased the plasma and red blood cell Se concentrations of adult horses. However, horses fed Se-enriched hay had higher plasma Se concentrations when compared to horses with access to the Se-containing trace mineral block or horses receiving no supplementary Se (P<0.0001), with mean plasma Se concentrations falling in the reference range considered adequate (>0.14mg/kg) for those horses fed Se-enriched hay. In summary, application of Se-enriched fertilizer increased the Se concentration of hay to a degree sufficient to meet the published dietary requirement for horses (0.1mg/kg DM), and feeding of Se-enriched hay was an effective method of Se supplementation of horses. [Copyright &y& Elsevier]

To characterize the ocular anomalies, determine their recurrence in families and assess the mode of inheritance of the most prevalent anomalies through pedigree analysis in a herd of Exmoor ponies. Thirty Exmoor ponies residing in south-western Ontario, Canada. Ophthalmic examination was performed using direct ophthalmoscopy, slit-lamp biomicroscopy and indirect ophthalmoscopy, pre- and post-pupillary dilation. Following compilation of ocular findings, pedigree analysis was conducted to assess the recurrence pattern of specific anomalies in families and the data were tested for significance for breed prevalence and gender dependence, using Fisher's exact test. Twenty-eight purebred ponies and two cross-breds, ranging from 14 days to 31 years were examined. A prominent brow above the eyes characteristic of this breed was a consistent periocular feature of adult ponies. In nine ponies, eyelid sarcoid, iris nevus, Mittendorf's dot, hyaloid artery remnant, and hyper-reflective vitreal strands were detected while the lesions recorded in the remaining 21 included macroblepharon, persistent pupillary membranes, iris hypoplasia, cataracts, focal choroidal or retinal pigment epithelium hypoplasia and optic nerve head coloboma. The most common ocular finding was cataracts seen mainly in females. Statistical tests on prevalence data confirmed a significant breed and sex association. Pedigree analysis favored a sex-linked mode of inheritance for cataracts in this line of Exmoor ponies. Although the ocular anomalies detected in this group have been previously reported in other breeds of horses, this is the first report of equine cataracts showing a familial trend suggestive of a sex-linked genetic defect. [ABSTRACT FROM AUTHOR]

Abstract: Accurate diagnosis of parasites within individual hosts remains a difficult task. Incorrect and/or inaccurate diagnosis restricts the potential for targeted treatment of individuals and limits our understanding of key epidemiological characteristics of potential pathogens of domestic stock. In this study, we compared the specificity and sensitivity of four diagnostic methods for determination of the presence and intensity of the cestode Anoplocephala perfoliata in horses. Over 400 horses from an abattoir in south-central Alberta were evaluated for the presence and number of cestodes. Thirty one horses were infected with 1 to >1000 worms. Diagnosis based upon faecal egg counts of horses with known numbers of worms was least accurate in detecting worm presence. Detection of circulating antibodies to the cestode was most sensitive using Western blot analysis (100%), but had lower specificity (87%). A serum-based ELISA had a lower sensitivity (70%) for detection of antibodies. A coproantigen ELISA had 74% sensitivity and 92% specificity, and there was a positive correlation between antigen concentration and tapeworm intensity. The coproantigen ELISA may have the potential as a diagnostic tool for determining the presence and intensity of this potentially pathogenic cestode. [ABSTRACT FROM AUTHOR]

The article presents a study which investigated the prevalence of methicillin resistant Staphylococcus aureus (MRSA) in nasal swabs of 45 horses in western Canada. The study found that the rate of colonization was 1.3% ± 5.84% and five of the 6 isolates were Canadian epidemic MRSA-5, a human clone that appears to predominate in horses in North America. It also determined that the other isolate was spa type 539, a sequence type 398 strain.

Objective--To estimate the association between climate and airborne pollen and fungal factors and chronic obstructive pulmonary disease (COPD) in horses. Sample Population--Data from 1,444 horses with a diagnosis of COPD. Procedure--The Veterinary Medical Database was used to identify records of horses admitted to veterinary teaching hospitals in the United States and Canada between 1990 and 1999. Rainfall, mean minimum and maximum temperature, and maximum monthly pollen and fungal spore (mold) counts recorded at the city closest to where the hospital is located were identified for each month data were reported to the Veterinary Medical Database. Associations between climatic and aeroallergen data and monthly prevalence of COPD were estimated by use of cross-correlation and logistic regression models. Results--Significant positive correlations were found between prevalence of COPD and rainfall 3 months previously, minimum temperature 1 and 2 months previously, total pollen counts measured 3 months previously, and total mold counts measured during the same month and 1 month previously. Conclusions and Clinical Relevance--Outdoor aeroallergens and climatic factors may contribute to the occurrence of COPD in horses. [ABSTRACT FROM AUTHOR]

Histopathological and genetic examinations were conducted on grayish-white solid hepatic nodules in 150 horses imported from Canada, in order to investigate larval Echinococcus multilocularis infection. Ten of the 150 horses (6.7%) were diagnosed with alveolar hydatid disease. The sequences of the mitochondrial cytochrome b genes obtained from all 10 polymerase chain reaction positive samples had 99 to 100% identity with the European haplotype E1 of E. multilocularis. Therefore, we concluded that the infections likely originated in Canada., (Copyright and/or publishing rights held by the Canadian Veterinary Medical Association.)

Medical records of equine patients presented for signs of abdominal pain to the Atlantic Veterinary College Teaching Hospital between 2000 and 2015 were reviewed. A total of 575 patients were enrolled, and the most common clinical findings, diagnoses, and outcomes are described. Potential predictors of survival to discharge were assessed. The most common diagnosis was large colon impaction (18.4%), followed by large colon volvulus (6.2%). Overall survival to discharge was 69%. The survival rates for horses were 82.9% for those with no diagnosis, 74.6% for those with large intestine lesions, and 38.5% for those with small intestine lesions. Significant predictors for non-survival were increasing age, increasing duration of colic signs, severity of colic, and a lesion in the small intestine. These data are important for veterinarians in the region who are treating cases of equine colic and advising clients., (Copyright and/or publishing rights held by the Canadian Veterinary Medical Association.)

Investigates an outbreak of methicillin-resistant Staphylococcus aureus (MRSA) in horses and humans in Canada. Transmission of the pathogen between horses and humans; Surveillance program launched to monitor MRSA infections.

Giardia intestinalis and Cryptosporidium spp. are commonly identified intestinal pathogens in humans and animals. In light of the clinical disease, production losses and zoonotic potential of both Giardia and Cryptosporidium infections, a study was undertaken to investigate the prevalence of these parasites in cattle, sheep, pigs and horses in Canadian farms at different geographical locations. A total of 104 cattle, 89 sheep, 236 pigs and 35 horses were sampled from 15 different Canadian geographical locations. Fecal samples were examined after concentration and immunofluorescent staining. Giardia and Cryptosporidium were present in cattle and sheep in six out of six sites sampled. In cattle the overall prevalence was 29% for Giardia and 20% for Cryptosporidium. Giardia was identified in 38% of sheep while 23% of sheep were positive for Cryptosporidium. Giardia and Cryptosporidium were identified in four out of six hog operations with an overall prevalence of 9% for Giardia and 11% for Cryptosporidium. All horse sampling locations (4/4) were positive for Giardia with 20% of animals infected. Cryptosporidium was identified in three out of four sampling sites with a prevalence of 17%. The prevalence of Giardia and Cryptosporidium was greater in calves and lambs compared to adults. This study demonstrates that both Giardia and Cryptosporidium appear to be prevalent in farm livestock.

This brief review focuses first on several epidemiologically relevant aspects of anaplasmosis, including: (1) the role of male ticks as intrastadial, biological vectors of Anaplasma through interhost transfer; (2) the application of molecular diagnostic assays in assessing tick vector competence and evaluating the role of chronically infected carrier cattle as sources of Anaplasma marginale infection in vector ticks; (3) opportunities provided by a recently developed in vitro tick feeding system in quantitating studies of tick-hemoparasite-host interactions. Lastly, current knowledge of the status of New World ticks as experimental and/or natural vectors of equine piroplasms is discussed.