Abstract

Background: Snakebite accidents are a public health problem in tropical countries and are listed as a tropical neglected disease by the World Health Organization (WHO). Annually, around 20,000 snakebites occur in Brazil and although the species Crotalus durissus is responsible for only 10% of the registered snakebite accidents, it has the highest fatality rate (around 1%). The maintenance of snakes in captivity has become an alternative for obtaining venom for the production of antivenom serum and immunological researches since the 20^th century. Snakes coming from nature are usually subjected to various stressors related to captivity and their health conditions can worsen if simple prophylactic management, as deworming, are not performed.

Objectives: This study aimed to determine some aspects of the parasitism by ascarids nematodes in C. durissus specimens; correlate the findings with corticosterone plasma levels; and determine if parasitized animals are more stressed ​​than non-parasitized ones.

Methods: A total of 12 rattlesnakes with and without ascarids had their blood withdrawn to evaluate biochemical and hematological parameters, and to determine plasma corticosterone.

Results: Snakes with ascarids presented higher corticosterone basal values, than dewormed animals, showing they were more stressed and, consequently, more susceptible to infections than animals free from ascarids. After the experiment, the rattlesnakes were euthanized to determine macroscopic and histhopatologic findings. Parasitized snakes showed more histopathological alterations, than dewormed ones.

Conclusion: Preventive medicine, hematological and fecal analysis, and adequate husbandry environment are important issues to keep snakes in healthy and welfare conditions to ensure specimen survival and longevity.

Keywords: Nematodes; Parasites; Ascarids; Stress; Captivity

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