Orthopaedic health status of horses from 8 riding schools - a pilot study

<p>Abstract</p> <p>Background</p> <p>Orthopaedic injury is the most common reason for lameness and wastage in sport and leisure horses. Studies on racehorses have shown differences in injury risk between trainers and training strategies. The aim was to study between riding school variation in orthopaedic health status by clinical examination and horses age, and control for change of examiner, in schools with previous high (n = 4) and low (n = 4) insurance utilisation.</p> <p>Methods</p> <p>Horses (n = 99) at 8 riding schools were examined for conformation, movement in all gaits, standing flexion tests and palpation by two veterinary surgeons (in some schools only one). Indexes of findings were created for total health, movements, limbs, conformation and back palpation.</p> <p>Results</p> <p>Logistic regression analyses showed that findings increased with age (walk, trot, canter, conformation left hind limb, palpation fore limbs, hooves and flexion tests) or decreased with age (conformation right fore limb). Significant differences in findings were found between riding schools and examiner for seven and eight criteria each (partly overlapping). Increasing indexes were significantly associated with one examiner (total health, movements, back palpation), increasing age (total health, movements) or more time at the school (limbs). The back palpation index was highest at 5 < 8 years since acquisition.</p> <p>Conclusion</p> <p>The age distribution differed markedly between riding schools and age affected several types of findings. This, combined with the two opposite groups of insurance use, shows that schools with low insurance utilisation had previously been able to "avoid" using the insurance, maybe even on similar types of cases if these were more promptly/differently handled indicating differential coverage of disease data in the insurance database. The examiner effect was clearly demonstrated. For some findings, the amount of clinical observations differed by school, even when examiner and age was adjusted for. Most findings were of minor importance, including slight movement irregularities. Orthopaedic status varies between riding schools. We hypothesize that this is associated with management factors that warrant further study.</p

Incidence of osteochondrosis (dissecans) in Dutch warmblood horses presented for pre-purchase examination

Data are lacking in the literature regarding the incidence of osteochondrosis (dissecans) [OC(D)] in relation to lameness evaluation in Dutch Warmblood horses. The objective of this retrospective study was to assess the incidence of radiological abnormalities consistent with osteochondrosis or osteochondrosis dissecans in 1,231 sound Dutch Warmblood (DW) horses presented for pre-purchase examination. Standardised (Dutch) pre-purchase examination protocols were evaluated. The pre-purchase examination included a clinical, lameness and radiological evaluation, performed at a private equine clinic in the Netherlands. Radiographical examination included views of the distal (DIP) and proximal (PIP) interphalangeal, metacarpo- and metatarsophalangeal (MCP/MTP), tarsocrural (TC) and femoropatellar (FP) joints. Radiographical evidence of OC(D) was found in 44.3% of clinically sound DW horses. In this study, 443 horses (36%, n = 1,231) had evidence of OCD and 102 horses (8.3%, n = 1,231) had evidence of OC on pre-purchase radiographs. The results also indicated that the TC joints were significantly more likely to be affected. A considerable number of horses did not demonstrate any lameness, although radiographs revealed OC(D)

Epidemiology of Exertional Rhabdomyolysis Susceptibility in Standardbred Horses Reveals Associated Risk Factors and Underlying Enhanced Performance

BACKGROUND: Exertional rhabdomyolysis syndrome is recognised in many athletic horse breeds and in recent years specific forms of the syndrome have been identified. However, although Standardbred horses are used worldwide for racing, there is a paucity of information about the epidemiological and performance-related aspects of the syndrome in this breed. The objectives of this study therefore were to determine the incidence, risk factors and performance effects of exertional rhabdomyolysis syndrome in Standardbred trotters and to compare the epidemiology and genetics of the syndrome with that in other breeds. METHODOLOGY/PRINCIPAL FINDINGS: A questionnaire-based case-control study (with analysis of online race records) was conducted following identification of horses that were determined susceptible to exertional rhabdomyolysis (based on serum biochemistry) from a total of 683 horses in 22 yards. Thirty six exertional rhabdomyolysis-susceptible horses were subsequently genotyped for the skeletal muscle glycogen synthase (GYS1) mutation responsible for type 1 polysaccharide storage myopathy. A total of 44 susceptible horses was reported, resulting in an annual incidence of 6.4 (95% CI 4.6-8.2%) per 100 horses. Female horses were at significantly greater risk than males (odds ratio 7.1; 95% CI 2.1-23.4; p = 0.001) and nervous horses were at a greater risk than horses with calm or average temperaments (odds ratio 7.9; 95% CI 2.3-27.0; p = 0.001). Rhabdomyolysis-susceptible cases performed better from standstill starts (p = 0.04) than controls and had a higher percentage of wins (p = 0.006). All exertional rhabdomyolysis-susceptible horses tested were negative for the R309H GYS1 mutation. CONCLUSIONS/SIGNIFICANCE: Exertional rhabdomyolysis syndrome in Standardbred horses has a similar incidence and risk factors to the syndrome in Thoroughbred horses. If the disorder has a genetic basis in Standardbreds, improved performance in susceptible animals may be responsible for maintenance of the disorder in the population

Plasma concentrations of steroid precursors, steroids, neuroactive steroids, and neurosteroids in healthy neonatal foals from birth to 7 days of age

BackgroundTransient hypothalamic-pituitary-adrenal axis dysfunction occurs in critically ill foals with sepsis and neonatal maladjustment syndrome (NMS). Cortisol is the most commonly measured steroid. However, a complex interaction of various steroid compounds might play a role in pathophysiology of this disorder.ObjectiveTo identify steroid compounds present at high concentrations at birth that rapidly and steadily decrease within the first 7 days of life in healthy foals and that might be supportive diagnosis of NMS and other neonatal disorders.AnimalsTen healthy neonatal Quarter Horse foals (5 females and 5 males).MethodsProspective study. Blood was collected in heparinized tubes within 30 minutes after birth, and at 12, 24, 48, 72, 96, 120, 144, and 168 hours of age. Plasma was separated and a panel of steroid compounds was analyzed using liquid chromatography-mass spectrometry. A nonlinear regression model was used to determine decay concentrations over time. Confidence intervals (CIs) were calculated and significance was set a P ≤ .05.ResultsFive compounds were identified: pregnenolone, progesterone, deoxycorticosterone, dehydroepiandrosterone, and dehydroepiandrosterone sulfate. Pregnenolone and progesterone concentrations rapidly decreased by 24 hours of age and remained low throughout the first 7 days of life. Their half-life (95% CI) was short at 3.7 (3.4, 4.0) and 4.5 (2.8, 6.1) hours, respectively. No statistical differences in the concentrations of these compounds were found between males and females.Conclusions and clinical relevanceProgesterone might be a useful marker for identifying continuous endogenous production of neuroactive steroids in foals with suspected NMS and other neonatal diseases

THE PREVALENCE OF ENTERIC PATHOGENS IN DIARRHEIC THOROUGHBRED FOALS IN BRITAIN AND IRELAND

A survey of 77 normal and 326 diarrhoeic foals in Britain and Ireland from 1987 to 1989 revealed a significantly higher prevalence of Group A rotaviruses and Aeromonas hydrophila in diarrhoeic foals. The prevalence of cryptosporidia, potentially pathogenic Escherichia coli, Yersinia enterocolitica and Clostridium perfringens was similar in normal or diarrhoeic foals. Rotaviruses had a similar prevalence in all age groups of scouring foals up to three months of age, with an overall prevalence of 37 per cent among diarrhoeic foals. The number of cases of diarrhoea varied considerably from year to year, but in all three years of the survey rotavirus was a significant pathogen. A comparison of diagnostic tests for rotavirus in the faeces showed electron microscopy (EM) and polyacrylamide gel electrophoresis (PAGE) to have similar sensitivity. The Rotazyme ELISA test kit was found to have the same sensitivity as a combination of EM and PAGE. A. hydrophila had an overall prevalence of 9 per cent among diarrhoeic foals, although its prevalence was higher in some age groups. A. hydrophila has not been established previously as a significant enteric pathogen in foals. Other putative pathogens found at very low prevalence were coronavirus, the putative picobirnavirus, Campylobacter spp. and Salmonella spp. No evidence was found of synergistic effects between rotavirus, cryptosporidia and potentially pathogenic E. coli. Neither coccidia nor non-Group A rotaviruses were found in any of the samples examined