Clinic and pathological and laboratory aspects of experimental poisoning by Bothrops alternatus venom in cattle

Pesquisa Veterinária Brasileira

Coelho, Cleide D.³  França, Ticiana N.¹  Tokarnia, Carlos H.²  Peixoto, Paulo V.²  Brito, Marilene F.⁴  Caldas, Saulo A.³  Graça, Flávio A.S.⁵ 

[1]Universidade Estácio de Sá, Rio de Janeiro

[2]Universidade Federal Rural do Rio de Janeiro, Seropédica, Brasil

[3]Universidade Federal Rural do Rio de Janeiro

[4]UFRRJ, Seropédica

[5]Universidade Castelo Branco, Rio de Janeiro

DOI  :  10.1590/S0100-736X2008000600008

来源: Colegio Brasileiro de Patologia Animal-CBPA

【 摘 要 】

The aim of thisstudy was to determine the clinical-pathological alterations and laboratoryfindings in cattle inoculated with Bothrops alternatus venom, with theintention of providing information for the establishment of diagnosis and differentialdiagnosis procedures, as well as to elucidate some obscurities observed in thepertinent literature. The lyophilized venom was diluted in 1 ml of physiologicsolution. It was administered to 5 bovines by the subcutaneous route at dosesof 0.0625, 0.125 and 0.25mg/kg body weight, and to 2 bovines by the intramuscularroute at doses of 0.25 e 0.45mg/kg. Six bovines died and the only animal thatsurvived, who had subcutaneously received the venom at a dose of 0.0625mg/kg,recovered. The first clinical signs were observed from 25min to 5h30min afterthe inoculation. The clinical evolution time varied from 7 hours 18 minutesto 92 hours. Regardless of the dose, the clinical picture was characterizedby swelling (hemorrhage/hematoma) at the site of inoculation, increase in bleedingtime and capillary refill time, paleness of mucous membranes and apathy. Thelaboratory exams revealed progressive normocytic normochromic anemia, thrombocytopenia,reduction in fibrinogen and total plasma proteins, decreased hematocrit andhemoglobin, and slight increase in creatine kinase and lactate dehydrogenase.When subjected to necropsy, the animals that received the venom through thesubcutaneous route showed large hematomas and hemorrhagic areas in the subcutaneoustissue, extending from the site of inoculation. The animals in which inoculationwas performed intramuscularly exhibited, in addition, intramuscular hemorrhage.The left endocardium showed extensive hemorrhagic lesions, and petechiae werefound 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 hemorrhage and coagulativemuscle necrosis in the vicinities of the inoculation site in the animals thatreceived the venom by the intramuscular route. These lesions were mild in themuscles close to the site of inoculation in the animals inoculated by the subcutaneousroute. The swelling on the site of inoculation and its surroundings was a consequenceof blood accumulation and not merely edema. Myoglobinuria and gross or microscopiclesions were not observed in the kidneys. This study indicates that B. alternatuscan lead adult bovines to death if they release all their venom during a bite.Conversely, since venomous ophidians can control the amount of poison they inoculateand they probably do not identify bovines as potential preys, it is likely thatthe number of accidents involving this species is small, which is in agreementwith the findings of the majority of the centers for anatomical-pathologicaldiagnosis in Brazil.

【 授权许可】

CC BY-NC