Abstract Maintenance of snakes at Butantan Institute started in the last century, intending to produce a different antivenom serum to reduce death caused by snakebites. Through a successful campaign coordinated by Vital Brazil, farmers sent venomous snakes to Butantan Institute by the railway lines with no cost. From 1908 to 1962, the snakes were kept in an outdoor serpentarium, where venom extraction was performed every 15 days. During this period, the snake average survival was 15 days. In 1963, the snakes were transferred to an adapted building, currently called Laboratory of Herpetology (LH), to be maintained in an intensive system. Although the periodicity of venom extraction remained the same, animal average survival increased to two months. With the severe serum crisis in 1983, the Ministry of Health financed remodeling for the three public antivenom producers, and with this support, the LH could be improved. Air conditioning and exhausting systems were installed in the rooms, besides the settlement of critical hygienic-sanitary managements to increase the welfare of snakes. In the early 1990s, snake survival was ten months. Over the years to the present day, several improvements have been made in the intensive serpentarium, as the establishment of two quarantines, feeding with thawed rodents, an interval of two months between venom extraction routines, and monitoring of snake health through laboratory tests. With these new protocols, average snake survival increased significantly, being eight years for the genus Bothrops, ten years for genus Crotalus and Lachesis, and four years for the genus Micrurus. Aiming the production of venoms of good quality, respect for good management practices is essential for the maintenance of snakes in captivity. New techniques and efficient management must always be sought to improve animal welfare, the quality of the venom produced, and the safety of those working directly with the venomous snakes.

Visto que alguns colubrídeos são capazes de causar envenenamento humano, fazem-se necessários estudos capazes de elucidar os mecanismos biológicos relacionados ao aparelho de veneno destes animais. Este estudo abordou características morfológicas e histoquímicas das glândulas de Duvernoy e supralabial de seis espécies de colubrídeos opistoglifodontes. Na maioria das espécies analisadas, a glândula de Duvernoy apresentou características de uma glândula seromucosa, com exceção a de Oxyrhopus guibei que não apresentou positividade à presença de proteínas indicando um caráter mucoseroso. Observou-se ainda, uma variação na quantidade das células serosas dentre as espécies estudadas. Esta variação pode estar relacionada com a presença de substâncias ricas em um complexo carboidrato-proteína e, conseqüentemente, com a função tóxica da secreção.

Since some colubrids can cause human envenomation, the importance of studies relating biological mechanisms to their venom apparatus is crucial. The present work dealt with morphological and histochemical characteristics of Duvernoy's gland of six opisthoglyphous colubrid species. The Duvernoy's gland of most species presented characteristics of a seromucous gland, except that of Oxyrhopus guibei, which did not show positive reaction to proteins indicating a mucoserous feature. We found variation in the quantity of serous cells among the species. This variation may be related to the presence of substances rich in carbohydrate-protein complex, and consequently to the toxic function of the secretion.

Micrurus corallinus (Merrem, 1820) kept in laboratory animal rooms swallow voluntarily various colubrid species. The most accepted species belong to the genera Sibynomorphus Fitzinger, 1843, Oxyrhopus Wagler, 1830 and Liophis Wagler, 1830. The voluntary feeding guaranteed resistance against pathogenic agents. The forced feeding was unsatisfactory due to stress resulting from handling, feeding frequency (30 days), susceptibility to pathogenic agents and high occurrence of pathologies.

The weight variation in Micrurus corallinus (Merrem, 1820) during the first 60 days in laboratory animal rooms was very remarkable. This fact demonstrates the difficulty in adaptation of these animals to the captive environment. The weight loss was observed in animals under voluntary feeding as well as forced feeding. The survival rate was significantly higher in voluntarily fed animals. Sex differences were also observed with higher survival rates for males. Low survival rates were observed in both sexes under forced feeding.