Paratuberculose e encefalomalácia simétrica focal em caprinos e ovinos.

Abstract

This paper reports paratuberculosis in sheep and goats for the first time in Brazil. On Farm 1 in a flock of 33 goats and 13 sheep, one adult female goat presented progressive weight loss during about one year, and soft feces during one month before death. All the animals from the flock were submitted to the comparative tuberculin test. One sheep was positive to the avian tuberculin (2.2%) and in two the results were inconclusive. On Farm 2, in a flock of 200 sheep and 80 goats, one adult ewe presented progressive weight loss during about one year, and soft feces during 20 days before death. All sheep older than four months of age and 23 goats were submitted to tuberculin test with avian tuberculin; 47 (25.4%) sheep were positive, 115 (61.5%) had inconclusive results, and 25 (13.4%) were negative. No positive tuberculin test were observed in the goats, but in 11 (47.8%) the test was inconclusive and in 12 (52.2%) was negative. At necropsy both affected animals had enlarged mesenteric lymph nodes. In the affected sheep, the gut wall was thickened and corrugated, mainly in the ileum and ileocecal valve. Histologically, granulomas with mainly foamy macrophages were observed in the lamina propria and submucosa of the gut, in mesenteric lymph nodes, and in the goat also in the liver. One tuberculin positive sheep and one tuberculin negative goat from Farm 1 were euthanized and necropsied. A mild thickened of the intestinal wall was observed grossly in both animals. Inflammatory infiltrate with mainly lymphocytes was observed on the submucosa and lamina propria of the gut. In the four cases acid-alcohol positive rods, positive for Mycobacterium spp. on immunohistochemical examination were observed in macrophages and lymphocytes. New studies are necessary to know the prevalence and economical impact of paratuberculosis in goats and sheep in Brazil, to determine control measures, and to evaluate the risk of human transmission.