Experimental poisoning by Bothropoides jararaca and Bothrops jararacussu in sheep: clinic-pathological and laboratory aspects

Aragao A.P., Tokarnia C.H., Graca F.A.S., Franca T.N., Coelho C.D., Caldas S.A. & Peixoto P.V. 2010. [Experimental poisoning by Bothropoides jararaca and Bothrops jararacussu in sheep: Clinic-pathological and laboratory aspects.] Envenenamento experimental por Bothropoides jararaca e Bothrops jararacussu em ovinos: aspectos clinico-patologicos e laboratoriais. Pesquisa Veterinaria Brasileira 30(9):717-728. Projeto Sanidade Animal Embrapa/UFRRJ, Seropedica, RJ 23890-000, Brazil. E-mail:paulaaragao.vet@gmail.com. The purpose of this study was to establish the clinic-pathological and laboratory changes in sheep inoculated with Bothropoides jararaca and Bothrops jararacussu venom to provide subsidies for the differential diagnosis of snake bites. The liofilized venoms were diluted in 1 ml saline and administrated subcutaneously to four sheep. Three of the animals died, and the one that received 0.5mg/kg (B. jararaca venom) recovered. First symptoms were observed from 7 minutes to 1 hour after inoculation, and the clinical course varied from 7 hours and 9 minutes to 21 hours and 59 minutes. The symptoms, independent of the dosage, were swelling of the inoculation site, increased bleeding time and capillary filling, tachycardia, dyspnea, pale mucous membranes and diminished reaction to external stimuli. Laboratory tests revealed pronounced normocytic and normochromic anemia, trombocytopenia, slight reduction of fibrogen and total plasmatic protein, in two animals diminished hematocrit, besides pronounced increase of creatinaquinase and lactic dehydrogenase. At necropsy, the main findings at the inoculation site and adjacent tissues were extensive hemorrhages in the sheep inoculated with jararaca venom, and predominantly edema in the two animals inoculated with jararacussu venom. In two sheep which received jararacussu venom, acute pulmonary edema was observed. Hemorrhage and edema as the main histopathological changes, besides necrosis of muscle fibers and vessels at the inoculation site and adjacent tissue was observed. The renal tubular necrosis was attributed to shock. The volume increase at the inoculation site and surroundings was mainly due to hemorrhage (B. jararaca) or edema (B. jararacussu).