Susceptibility of Psammomys obesus and Meriones tristrami to tachyzoites of Neospora caninum.

The susceptibility of Psammomys obesus (sand rat) and Meriones tristrami (Tristram's jird) to Neospora caninum was investigated by subcutaneous (s.c.) and intraperitoneal (i.p.) inoculation of 10-fold doses of culture-derived tachyzoites. Groups of 5 animals were inoculated with doses of 10-10(7) parasites via each route of inoculation. All but 2 of the sand rats inoculated with doses of 10-10(4) parasites succumbed to the infection by 7-18 days postinfection. All jirds inoculated with 10(7) tachyzoites succumbed by 5-16 days postinfection and those inoculated with 10(6) tachyzoites by 9-25 days. A considerable proportion of the jirds inoculated with 10-10(5) tachyzoites survived. Fibrinous peritonitis with ascites containing numerous tachyzoites was observed in the i.p.-inoculated sand rats and jirds that succumbed to the infection. In the jirds, tachyzoites were also found in pleural exudate. A considerable number (42.8%) of the jirds inoculated s.c. or i.p. exhibited neuromuscular symptoms, expressed in ataxia, head tilt, circling movement, and posterior paralysis. Seven successive passage of tachyzoites were achieved in sand rats with doses of 10(5) parasites and in jirds with doses of 10(7) parasites. All surviving jirds became seroconverted and were immune to lethal challenge.

Congenital thymic aplasia in a Holstein-Israeli female calf.

An unusual case of congenital thymic aplasia in a Holstein-Israeli female calf is described. The most prominent clinical findings were diarrhoea and weakness. At necropsy, the only significant pathological finding was the marked decrease in thymus size. Histologically, this organ was composed of loose connective tissue in which a few lymphocytes were scattered randomly.

Gangrene in the distal extremity of all 4 limbs of a 2-week-old foal.

Wet gangrene developed in all 4 limbs following repair of a rupture in the lower urinary tract in a 2-week-old foal. Dehydration and hypoxemia are suspected as the inciting causes of the necrosis.

Case report: primary fibrosarcoma of the liver in a cow.

An unusual case of primary fibrosarcoma of the liver in a cow is described. The most prominent pathological findings were severe abdominal haemorrhage and neoplastic masses confined to the liver only. Histologically, spindeloid cells arranged in interlacing bundles running in various directions and numerous areas of necrosis and ossification were randomly scattered in the neoplasm.

Outbreak of fatal salmonellosis in cats following use of a high-titer modified-live panleukopenia virus vaccine.

A 14-week-old kitten from a private cattery was examined because of an acute onset of recumbency and epistaxis 10 days after receiving a high-titer modified-live virus vaccine containing panleukopenia virus, calicivirus, and herpesvirus components. The kitten died the following day, and intestinal crypt necrosis; hepatic, splenic, and lymph node inflammation and necrosis; and pneumonia were seen at necropsy. Salmonella typhimurium was isolated from mesenteric lymph nodes and the spleen. The breeder reported that 4 other kittens had died in the previous month, each within 1 to 2 weeks after being vaccinated with the same modified-live virus vaccine. Carcasses of 3 kittens were available for examination, and Salmonella sp was isolated from mesenteric lymph nodes of all 3. Villus crypt necrosis and secondary fibrosis were also found. Three of the remaining 12 kittens in the cattery were also found to be shedding Salmonella sp in their feces. Clinical and pathologic findings in these kittens were likely attributable to salmonellosis and panleukopenia, and suggest that mild immunosuppression induced by vaccination could have facilitated development of fatal salmonellosis in subclinical carrier kittens. However, we cannot prove that vaccination actually played any role.

Severe hepatopathy in geese and broilers associated with ochratoxin in their feed.

The feeding of a shipment of imported corn was associated with a severe reduction in growth and increased mortality in geese, and increased mortality in broilers. Pathological examinations revealed hepatopathy, visceral gout and mild nephropathy in geese, and in broilers an hepatopathy, which was often severe, and ascites. Samples of feed from affected geese farms were examined for up to 24 mycotoxins, and ochratoxin was found in 6 of 15 samples at levels up to 930 ng/g. The syndrome was experimentally reproduced by feeding geese and broilers suspect feeds with the natural ochratoxin contamination. It is believed that another, unidentified, mycotoxin was the major cause of the hepatotoxicity, and that ochratoxin served in this case as an indicator of a multi-mycotoxin involvement.

Interstitial cell (Leydig) tumor in an eland (Taurotragus oryx).

We observed an interstitial cell tumor in an 18-mo-old captive eland bull (Taurotragus oryx) in Tel Aviv, Israel. The histological description of the tumor in the eland was similar to that described in cattle; however, the appearance of a moderate amount of lipid vacuoles in the cytoplasm of the neoplastic cells was uncharacteristic for bovine interstitial cell tumors. The eland also had clinical signs of gynecomastia.

Myocarditis following envenoming with Vipera palaestinae in two horses.

Cardiac disease developed several days to weeks after resolution of local inflammation caused by envenoming by Vipera palaestinae in two horses. In one horse (case A), referred to the hospital for recurrent abdominal pain 8 days after envenoming, a tachyarrhythmia was detected; ventricular premature depolarizations were diagnosed by ECG. A second horse (case B) was found dead without premonitory signs 60 days after envenoming. In both horses, there was extensive necrosis of cardiac ventricular tissues.

Field observations in Israel on hypersensitivity in cattle, sheep and donkeys caused by Culicoides.

Hypersensitive lesions in the skin of sheep, cattle and donkeys from various regions in Israel are described. No cause other than insect bites was found. The animals were free of ticks, lice, fleas and blackflies, and of all the prevailing insect groups; Culicoides spp were considered as the most probable cause of the hypersensitivity. Lesions on the legs and abdomen were attributed mainly to C obsoletus Meigen, C schultzel gp and C puncticollis Becker, and less to C imicola Kieffer. Lesions on the back, flanks, neck and head were attributed mainly to C imicola, less to C newsteadi Austen and rarely to C pulicaris Linnaeus.

Perianal squamous cell carcinoma in goats.

Two cases of squamous cell carcinoma arising from the perianal skin of aged female Sannen crossbred goats are described. The occurrence of a tumour in this specific location is very rare, and the presence of the identical tumour in two animals of the same herd is unusual.

Concurrent Hepatozoon canis and Toxoplasma gondii infections in a dog.

A female 1-year-old dog died suddenly and was submitted for necropsy. Numerous grey-tan-colored nodules were seen in the lungs, brain and lymph nodes. Microscopically, the predominant lesion was necrosis associated with numerous Toxoplasma gondii tachyzoites. The parasites reacted positively with anti-T. gondii serum in an immunohistochemical test. Schizonts of Hepatozoon canis were seen in sections of lymph nodes and the spleen.

A case of natural hydatidosis in a baboon.

Four large and several smaller cysts of Echinococcus granulosus were found in the liver of a baboon submitted for necropsy. Three of the large cysts had an atypical structure and were packed with a semi-solid mass of collapsed daughter cysts, small cysts containing fluid and involuted membranes. This atypical structure has been reported previously though only in baboons.

Canine GM1-gangliosidosis. A clinical, morphologic, histochemical, and biochemical comparison of two different models.

The clinical, morphologic, histochemical, and biochemical features of GM1-gangliosidosis in two canine models, English Springer Spaniel (ESS) and Portuguese Water Dog (PWD), have been compared. The disease onset, its clinical course, and survival period of the affected dogs were similar in both models. Skeletal dysplasia was noted radiographically at 2 months of age, whereas at 4 1/2 months of age there was progressive neurologic impairment. However, dwarfism and coarse facial features were seen only in ESS. Both models had similar deficiency in activity of lysosomal beta-galactosidase, but possessed a normal protein activator for GM1-beta-galactosidase. Both models stored GM1-ganglioside, asialo-GM1, and oligosaccharides in brain. Furthermore, only the PWD stored glycoproteins containing polylactosaminoglycans in visceral organs, and neither model stored them in the brain. Morphologically, both models demonstrated similar storage material in multiple tissues and cell types. The ultrastructure of the storage material was cell-type specific and identical in both models. However, some differences in the lectin staining pattern were noted. Our clinical, biochemical, and histochemical findings indicate that PWD and ESS may represent two different mutations of the beta-galactosidase gene. Moreover, the authors conclude that it is difficult, and inappropriate, to apply the human classification of GM1-gangliosidosis (i.e. infantile, juvenile, and adult forms) to these canine models.

Adult onset lysosomal storage disease in a Tibetan terrier: clinical, morphological and biochemical studies.

We describe a novel late-onset lysosomal lipid storage disease affecting a Tibetan terrier. The principal clinical manifestations include visual loss, progressive cerebellar ataxia and dementia. A necropsy of an affected 10-year-old dog demonstrated cerebellar atrophy. Histological analysis revealed extensive loss of retinal ganglion cells and cerebellar Purkinje cells, and mild to moderate loss of neurons in the cerebrum, basal ganglia and spinal cord. There were generalized neuronal hypertrophy and multifocal neuronal necrosis associated with the presence of enlarged macrophages. Neurons and perineuronal macrophages contained cytoplasmic granules that stained with PAS, luxol fast blue and several lectins. The granules were sudanophilic and autofluorescent. Electron microscopic analysis revealed lysosomes laden with lamellated membrane structures in neurons, pancreatic ductal and centroacinar cells and in cultured fibroblasts. These findings indicate lysosomal storage of both lipid and carbohydrate. Biochemical analysis of brain lipids and numerous lysosomal enzyme assays of leukocytes and cultured fibroblasts were unsuccessful in elucidating the underlying enzyme defect, although a generalized increase of brain gangliosides was noted.

Cardiomyopathy in cattle induced by residues of the coccidiostat maduramicin in poultry litter given as a feedstuff.

An experimental feeding trial was conducted in order to substantiate an hypothesis on the aetiology of a previously unrecorded cardiomyopathic syndrome in beef cattle in Israel. It was believed that residues of the ionophore maduramicin (Cygro; American Cyanamid) in poultry litter fed to cattle, after the maduramicin had been incorporated into broiler feed as a coccidiostat, were the cause of the cardiomyopathy. Three groups of 5 heifers were fed for several weeks (1) poultry litter from a field case, containing 4.8 ppm maduramicin; (2) poultry litter to which maduramicin was added to give a concentration of 12 ppm; (3) poultry litter with no maduramicin (control). Clinical, biochemical, necropsy and histopathological findings showed that maduramicin residues are cardiotoxic, even at the lower level of maduramicin fed, which is commonly encountered in poultry litter in Israel.