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101.
Altered intestinal permeability is implicated in the pathogenesis of diverse equine medical conditions including alimentary laminitis and protein-losing enteropathies associated with parasitic infection. The aims of this study were to assess the feasibility of applying the 51Cr-EDTA absorption test for the assessment of intestinal permeability in the horse, and to apply this test in horses with experimentally induced alterations in gastrointestinal function. Four healthy ponies were administered 36 MBq of 51Cr-EDTA via naso-gastric tube, and urine samples were collected into polythene bags strapped to the pony's abdomen. Total urine voided every 6 h was collected during each test, and 1 ml samples were taken for measurement of gamma-radiation. Urinary recovery of 51Cr-EDTA was measured following intravenous atropine sulphate or bethanecol, and following 22 and 46 days of administration of 250,000 third-stage cyathostome larvae. There was no significant difference in urinary 51Cr-EDTA recovery following the control treatment, and following atropine or bethanecol administration, but significant increases were detected in the animals with experimental cyathostome infection consistent with increased permeability of the intestinal membrane. Motility modifying agents (bethanecol and atropine) did not affect absorption of 51Cr-EDTA, suggesting that subtle changes in motility might not affect the ability of this test to detect altered intestinal permeability. The finding of increased urinary recovery of 51Cr-EDTA in ponies with cyathostome infection suggests that 51Cr-EDTA may be a useful marker for assessment of intestinal permeability in the horse. 相似文献
102.
Denwood MJ Love S Innocent GT Matthews L McKendrick IJ Hillary N Smith A Reid SW 《Veterinary parasitology》2012,188(1-2):120-126
The faecal egg count (FEC) is the most widely used means of quantifying the nematode burden of horses, and is frequently used in clinical practice to inform treatment and prevention. The statistical process underlying the FEC is complex, comprising a Poisson counting error process for each sample, compounded with an underlying continuous distribution of means between samples. Being able to quantify the sources of variability contributing to this distribution of means is a necessary step towards providing estimates of statistical power for future FEC and FECRT studies, and may help to improve the usefulness of the FEC technique by identifying and minimising unwanted sources of variability. Obtaining such estimates require a hierarchical statistical model coupled with repeated FEC observations from a single animal over a short period of time. Here, we use this approach to provide the first comparative estimate of multiple sources of within-horse FEC variability. The results demonstrate that a substantial proportion of the observed variation in FEC between horses occurs as a result of variation in FEC within an animal, with the major sources being aggregation of eggs within faeces and variation in egg concentration between faecal piles. The McMaster procedure itself is associated with a comparatively small coefficient of variation, and is therefore highly repeatable when a sufficiently large number of eggs are observed to reduce the error associated with the counting process. We conclude that the variation between samples taken from the same animal is substantial, but can be reduced through the use of larger homogenised faecal samples. Estimates are provided for the coefficient of variation (cv) associated with each within animal source of variability in observed FEC, allowing the usefulness of individual FEC to be quantified, and providing a basis for future FEC and FECRT studies. 相似文献
103.
Reardon RJ Boden LA Mellor DJ Love S Newton JR Stirk AJ Parkin TD 《Equine veterinary journal》2012,44(5):564-569
Reasons for performing study: Superficial digital flexor (SDF) tendinopathy is a common injury in Thoroughbred horses racing over hurdles. Identification of risk factors may allow the introduction of measures to minimise the incidence of this injury. Objective: To identify risk factors for SDF tendinopathy in Thoroughbred horses in hurdle races in the UK. Methods: Potential risk factors for SDF tendinopathy were studied between 1 January 2001 and 31 December 2009 using a retrospective cohort study design with 1031 case starts and 168,637 control starts. Potential risk factors were screened using univariable logistic regression prior to multivariable model building. Results: In the final multivariable model, 20 statistically significant risk factors were identified. Variables found to be associated with increased odds of SDF tendinopathy included: firmer going; increased horse age at first race; having had a previous SDFT injury; and racing in the summer compared to other seasons. Variables found to be associated with decreased odds included: being trained by a more successful trainer; and having raced more frequently in the preceding 9–12 months. Conclusions: This study identified multiple risk factors associated with SDF tendinopathy, some of which are difficult to explain with the current data source. Factors resulting in increased cumulative horse and tendon fatigue (increased years in racing; carrying increased weight; and racing over longer distances), firm ground, and the presence of previous tendon injury should be considered when attempting to reduce the likelihood of sustaining SDF tendinopathy. Potential relevance: The results will facilitate the development of strategies to improve the overall safety of horses in hurdle racing in the UK. 相似文献
104.
H Ülker M Küçük A Ylmaz M Yörük L Arslan DM deAvila JJ Reeves 《Reproduction in domestic animals》2009,44(1):37-43
This study was designed to evaluate the effectiveness of recombinant Ovalbumin-LHRL (OL) immunization on changes in testicular size, histological appearance and testosterone production in buck kids. Thirty native buck kids at 18 weeks of age were divided into three groups, control (n = 10), immunization (n = 10) and castration (n = 10) groups. Immunized animals received OL protein generated by recombinant DNA technology. Ultrasonographic and histological examinations of the testes were performed. Animals were slaughtered at 44 weeks of age. Semen and epididymides were evaluated for the presence of sperm cells. Immunized animals generated anti-LHRH antibodies. Testosterone production, testicular and accessory glands development and sperm production were suppressed in the immunized animals (p < 0.01). Semineferous tubule diameters decreased (p < 0.01), basal membrane of the tubule was thickened and hyalinized in immunized kids. Immunization affected ultrasonographic appearance of the testes drastically. While testes of control animals gained their normal ultrasonographic appearance as the age increased, immunized animals had uniform hypoechogenic testicular structure as observed at 18 weeks of age until slaughter. Simultaneous histological and ultrasonographic evaluations indicated that the changes in testicular histology could partly be monitored via ultrasonographic imaging; nevertheless, it is difficult to claim that ultrasonographic image reflects the exact changes in such instances. In conclusion, these results indicate that recombinant OL fusion protein is effective in immunocastration in buck kids and has a potential to be used as an alternative to physical castration. Further researches should be conducted to help assessing reproductive status of testes from ultrasound images. 相似文献
105.
GW Smith MP Gerard NB Campbell DM Foster SM Smith JL Davis 《Australian veterinary journal》2009,87(12):487-491
Objective To develop a simple and effective surgical technique for third‐compartment cannulation in alpacas. Design Prospective study using six adult male alpacas. Methods General anaesthesia was induced and a polyurethane gastrostomy tube was surgically implanted into the distal portion of the third compartment. Results Three of the alpacas retained their cannulas for a 100‐day period; however, three cannulas were dislodged during the study. Two of the three dislodged cannulas were replaced during a second surgical procedure. Cannulas were well tolerated by the alpacas and all animals remained clinically healthy during the study period. Third compartment contents did not leak from the cannulation site. The tubes were manually removed following the completion of the study and the small defect in the body wall quickly healed over in all animals. Conclusion Surgical placement of polyurethane tubes designed for percutaneous endoscopic gastrostomy is a useful method of cannulating the third compartment in camelids. This technique can be used for experimental studies and possibly could be used for nutritional support and fluid therapy in sick camelids that might need long‐term care. 相似文献
106.
Congenital dyserythropoietic anaemia (CDA) is a heterogeneous group of rare genetic disorders that in humans is characterised by ineffective haematopoiesis with morphological abnormalities in erythroid precursor cells and secondary iron overload. In the 1990s, a syndrome of CDA with dyskeratosis and progressive alopecia was reported in Poll Hereford calves in Canada and the USA. We report the clinical and pathological findings in two Poll Hereford calves with this syndrome from separate properties in South Australia. The animals had a variably severe anaemia, associated with abnormal nucleated red blood cells in peripheral blood, and large numbers of rubricytes and metarubricytes with a characteristic nuclear ultrastructure in the bone marrow. Both calves were born with a wiry hair coat and a progressively ‘dirty‐faced’ appearance associated with hyperkeratosis and dyskeratosis (apoptosis). 相似文献
107.
108.
109.
Foote CE Love DN Gilkerson JR Rota J Trevor-Jones P Ruitenberg KM Wellington JE Whalley JM 《Veterinary immunology and immunopathology》2005,105(1-2):47-57
The envelope glycoprotein D of equine herpesvirus 1 (EHV-1 gD) has been shown in laboratory animal models to elicit protective immune responses against EHV-1 challenge, and hence is a potential vaccine antigen. Here we report that intramuscular inoculation of EHV-1 gD produced by a recombinant baculovirus and formulated with the adjuvant Iscomatrix elicited virus-neutralizing antibody and gD-specific ELISA antibody in the serum of over 90% of adult mixed breed horses. The virus-neutralizing antibody responses to EHV-1 gD were similar to those observed after inoculation with a commercially available killed EHV-1/4 whole virus vaccine. Intramuscular inoculation of EHV-1 gD DNA encoded in a mammalian expression vector was less effective in inducing antibody responses when administered as the sole immunogen, but inoculation with EHV-1 gD DNA followed by recombinant EHV-1 gD induced increased gD ELISA and virus-neutralizing antibody titres in six out of seven horses. However, these titres were not higher than those induced by either EHV-1 gD or the whole virus vaccine. Isotype analysis revealed elevated gD-specific equine IgGa and IgGb relative to IgGc, IgG(T) and IgA in horses inoculated with EHV-1 gD or with the whole virus vaccine. Following inoculation of pregnant mares with EHV-1 gD, their foals had significantly higher levels of colostrally derived anti-gD antibody than foals out of uninoculated mares. The EHV-1 gD preparation did not induce a significant mean antibody response in neonatal foals following inoculation at 12 h post-partum and at 30 days of age, irrespective of the antibody status of the mare. The ability of EHV-1 gD to evoke comparable neutralizing antibody responses in horses to those of a whole virus vaccine confirms EHV-1 gD as a promising candidate for inclusion in subunit vaccines against EHV-1. 相似文献
110.