Aspectos clínico-patológicos e laboratoriais do envenenamento experimental por Bothrops alternatus em bovinos / Clinic and pathological and laboratory aspects of experimental poisoning by Bothrops alternatus venom in cattle

RESUMO

Esse estudo teve como objetivo determinar as alterações clínico-patológicas e os achados laboratoriais em bovinos inoculados com a peçonha de Bothrops alternatus, no intuito de fornecer subsídios para o estabelecimento do diagnóstico e do diagnóstico diferencial, bem como esclarecer pontos obscuros da literatura pertinente. O veneno liofilizado foi diluído em 1 ml de solução fisiológica e administrado a cinco bovinos, por via subcutânea, nas doses de 0,0625, 0,125 e 0,25 mg/kg e a dois outros, por via intramuscular, nas doses de 0,25 e 0,45 mg/kg. Seis bovinos foram a óbito e um que recebeu a dose de 0,0625mg/kg, por via subcutânea, recuperou-se. Os sinais clínicos tiveram início entre 25 minutos a 5 horas 30 minutos após a inoculação. O período de evolução variou de 7 horas 18 minutos a 66 horas 12 minutos. Um animal recuperou-se após 92 horas. O quadro clínico, independentemente das doses, caracterizou-se por aumento de volume (hemorragia/hematoma) no local da inoculação, tempo de sangramento aumentado, mucosas hipocoradas e apatia. O exame laboratorial revelou progressiva anemia normocítica normocrômica, trombocitopenia, redução de fibrinogênio e proteínas plasmáticas totais, hematócrito e hemoglobina diminuídos, além de leve aumento dos níveis de creatinaquinase e desidrogenase lática. Á necropsia, havia, a partir do local da inoculação, extensos hematomas e áreas de hemorragia no tecido celular subcutâneo dos animais que receberam o veneno por via subcutânea; nos animais inoculados por via intramuscular, adicionalmente, havia hemorragia intramuscular. O endocárdio esquerdo apresentava extensas hemorragias e verificaram-se petéquias na serosa do rúmen e do omaso e na mucosa do abomaso e da vesícula biliar. Em cinco animais, o cólon, reto e região perirrenal estavam envoltos por coágulos de sangue. Ao exame histológico observou-se, além do quadro hemorragíparo, necrose muscular coagulativa, acompanhada de hemorragia, no entorno do...

ABSTRACT

The aim of this study was to determine the clinical-pathological alterations and laboratory findings in cattle inoculated with Bothrops alternatus venom, with the intention of providing information for the establishment of diagnosis and differential diagnosis procedures, as well as to elucidate some obscurities observed in the pertinent literature. The lyophilized venom was diluted in 1 ml of physiologic solution. It was administered to 5 bovines by the subcutaneous route at doses of 0.0625, 0.125 and 0.25mg/kg body weight, and to 2 bovines by the intramuscular route at doses of 0.25 e 0.45mg/kg. Six bovines died and the only animal that survived, who had subcutaneously received the venom at a dose of 0.0625mg/kg, recovered. The first clinical signs were observed from 25min to 5h30min after the inoculation. The clinical evolution time varied from 7 hours 18 minutes to 92 hours. Regardless of the dose, the clinical picture was characterized by swelling (hemorrhage/hematoma) at the site of inoculation, increase in bleeding time and capillary refill time, paleness of mucous membranes and apathy. The laboratory exams revealed progressive normocytic normochromic anemia, thrombocytopenia, reduction in fibrinogen and total plasma proteins, decreased hematocrit and hemoglobin, and slight increase in creatine kinase and lactate dehydrogenase. When subjected to necropsy, the animals that received the venom through the subcutaneous route showed large hematomas and hemorrhagic areas in the subcutaneous tissue, extending from the site of inoculation. The animals in which inoculation was performed intramuscularly exhibited, in addition, intramuscular hemorrhage. The left endocardium showed extensive hemorrhagic lesions, and petechiae were found on the serosae of rumen, omasum, abomasum and gall bladder. The colon, rectum and perirenal areas were surrounded by clotted blood in three animals. Besides hemorrhage, the histological examination revealed...