A syndrome of anaemia, immunodeficiency and peripheral ganglionopathy in Fell pony foals

Fell pony foals developed a syndrome of anaemia, immunodeficiency and peripheral ganglionopathy. They became ill in the second or third week, and died in the second or third month of life. Clinical and pathological investigations revealed severe anaemia associated with small numbers of late erythroid precursors in bone marrow, small thymi, an absence of secondary lymphoid follicles, a lack of plasma cells and neuronal chromatolysis involving trigeminal, cranial mesenteric and dorsal root ganglia. Some of the foals had cryptosporidial enteritis and adenoviral bronchopneumonia and pancreatitis. The clinical and pathological findings were compatible with an intrinsic defect.

Comparison of histology with maternal and fetal serology for the diagnosis of abortion due to bovine neosporosis

An indirect fluorescent antibody test was applied to sera from normally calving and aborting cows and to samples of pleural fluid from their aborted calves, and the antibody titres were compared with histology and immunocytochemistry for the diagnosis of Neospora-associated abortion. Two groups of aborting cows and a third group of cows which had calved normally were used; group A consisted of 36 cows which aborted calves showing characteristic non-suppurative inflammatory lesions in which Neospora was demonstrated by immunocytochemistry, group B consisted of 100 cows which aborted calves without histological evidence of neosporosis, and group C consisted of 128 normally calved cows which were sampled within one month of calving. Serology on the maternal sera and fetal fluids was highly specific and sensitive for Neospora infection although 5 per cent of the cows which aborted Neospora-negative calves and 4.7 per cent of the normally calved cows were also seropositive. Anti-Neospora antibodies were also detected in 7 per cent of the samples of fetal fluid from Neospora-negative abortions.

Pulmonary venous thrombosis in caprine Pasteurella pneumonia

A 3-year-old Angora goat that developed acute fibrinous pleuropneumonia associated with Pasteurella haemolytica infection had thrombotic occlusion of a large pulmonary vein. Thrombosis of pulmonary capillaries occurs in pneumonic pasteurellosis, but large vessels are not commonly affected. This unusual lesion may reflect the procoagulant effect of pasteurella endotoxin on vascular endothelium. An incidental observation was the presence of myocardial-type muscle fibres in the tunica media of the pulmonary vein.

Results of a survey to determine whether Neospora is a significant cause of ovine abortion in England and Wales

Between January and April 1995, the brains and hearts of 281 aborted lambs derived from 209 submissions to veterinary investigation centres in England and Wales were examined histologically. One-hundred-and-seventy-nine samples of fetal pleural fluid from these lambs and 141 from lambs not examined histologically were examined for antibodies to Neospora by an indirect fluorescent antibody test. Non-suppurative myocarditis and encephalitis were present in nine lambs. Immunocytochemistry using antisera against Neospora caninum and Sarcocystis species resulted in no labelling but anti-sera to Toxoplasma gondii revealed labelled organisms in four lambs. No significant antibody titres against Neospora were detected in any of the samples of fetal pleural fluid. These results suggest that Neospora infection is not associated with significant numbers of abortions in sheep in England and Wales.

Diagnosis of grass sickness by ileal biopsy

Ileal biopsies were obtained from 18 horses with grass sickness, 15 horses with other alimentary disease and three horses without gastrointestinal disease. Samples of small intestine were also obtained from nine cases of obstruction due to small intestinal strangulation. Histological examination revealed that severe enteric neuropathy in the absence of other significant morphological changes was confined to the horses with grass sickness.

Enteric neuropathy in horses with grass sickness

The degeneration of enteric neurones has been recorded in grass sickness, but the distribution of the lesions in the gut and their possible relationship with the severity of the clinical signs has not been established. Samples obtained from 11 anatomically defined sites along the gastrointestinal tract of eight control horses without gastrointestinal disease, five horses with acute grass sickness and three horses with chronic grass sickness were examined histologically. The organisation of the enteric ganglia was similar to that in other large mammalian species. Minor exceptions included the presence of fundic mucosal nerve cell bodies and blood vessels within submucosal ganglia. All the horses with grass sickness had severe enteric neuropathy, widespread in the acute cases but localised to the distal small intestine in the chronic cases. These neuronal lesions are consistent with, and may explain the intractable gastrointestinal propulsive deficit that characterises grass sickness.