No abstract

The equine sarcoid, a locally aggressive, fibroblastic skin tumour, is the most common dermatological neoplasm reported in horses; there is no consistently effective therapy. It is widely accepted that bovine papillomavirus (BPV) types 1 and 2 are associated with the pathogenesis of sarcoid disease. Most sarcoids appear to contain detectable viral DNA and RNA and are also known to express the BPV types 1 and 2 major transforming protein, E5, but appear not to produce infectious virions. While the mode of transmission of infection has not been elucidated, viral gene expression, in particular of E5, may contribute to virus persistence and disease pathogenesis by downregulating MHC class I expression. Here, the pathology and epidemiology of the sarcoid and its association with BPV is reviewed; the transforming functions of the BPV oncoproteins and their possible role in sarcoid pathogenesis are discussed; and the practical implications of BPV infection for diagnostic and therapeutic purposes are considered.

No abstract

Details of the management, feeding, level of activity and routine health care of horses in Scotland and the five northernmost counties in England were recorded through a stratified random sample of horse owners who had responded to a previous survey. Sixty-eight per cent of the horses were kept where their owners resided, and 32 per cent were kept away from the owner's home. More than 99 per cent were turned out to grazing for at least part of the year and 81 per cent were stabled for at least part of the time, most commonly bedded on straw (50 per cent) or shavings (34 per cent). Hay was fed to 87 per cent, sugar beet pulp to 64 per cent and commercially prepared concentrate mixes to 60 per cent of the horses. Hacking was the most popular activity (52 per cent of horses) followed by riding/pony club events (28 per cent) and showing (21 per cent). The majority of the horses were involved in more than one activity. There were an estimated 0.88 veterinary visits per horse per year and 29 per cent of the horses were reported to suffer from at least one permanent or recurrent health disorder. The median annual numbers of administrations of vaccines (influenza and tetanus) and anthelmintics were one and seven respectively per horse, and each horse was shod a median seven times. There were significant differences in the management of horses kept in different types of premises and in areas of different human population density.

The clinicopathological features of 50 cases of equine hepatic disease were reviewed. There was a wide range of clinical signs and at least 50 per cent of the animals exhibited either dull demeanour, anorexia, abdominal pain, cerebral dysfunction and/or weight loss. Life-threatening complications of hepatic failure recorded were: gastric impaction in 10 cases, bilateral laryngeal paralysis in seven cases and coagulopathy in five cases. All the cases had high activities of gamma-glutamyl transferase (GGT) and most had high activities of glutamate dehydrogenase (GLDH) and high concentrations of bile acids. Fewer of the horses had abnormal concentrations of bilirubin, albumin and globulin. The horses that were euthanased or died had significantly higher concentrations of GGT, GLDH and bile acids than the survivors. There were biochemical data for 18 cases with signs of hepatic encephalopathy, all of them had plasma ammonia levels greater than 90 micromol/litre but this was not significantly correlated with the clinical severity of the condition. Half of the cases with hepatic encephalopathy were hyperglycaemic, none was hypoglycaemic, and none had abnormally low levels of plasma urea.