Maintenance of venomous snakes in captivity for venom production at Butantan Institute from 1908 to the present: a scoping history

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.(AU)

Maintenance of venomous snakes in captivity for venom production at Butantan Institute from 1908 to the present: a scoping history

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.(AU)

Estudo anatômico, morfológico, histoquímico e ultra-estrutural da glândula de Duvernoy de seis espécies de colubrídeos opistóglifos (Serpentes - Colubridae - Xenodontinae) / Anatomical, morphological, histochemical and ultra structural study of Duvernoy´s gland of six species of opisthoglyphous colubrids (Serpentes - Colubridae - Xenodontinae)

Os colubrídeos tem sido responsáveis por diversos acidentes graves, inclusive fatais, em seres humanos por todo o mundo. No Hospital Vital Brazil do Instituto Butantan, em São Paulo, 40% dos acidentes ofídicos registrados são causados por serpentes consideradas não-peçonhentas. Dentre estas, 97,3% pertencem à família Colubridae, onde 54,5% apresentam dentição áglifa e 42,8% dentição opistóglifa. Contudo, alguns acidentes envolvendo os colubrídeos opistóglifos podem desencadear manifestações clínicas semelhante ao acidente botrópico. Este fato tem causado muitas discussões, pois devido a um diagnóstico errôneo ou pela gravidade do acidente, muitas vezes é administrado o soro anti-botrópico, que em muitos casos pode ser ineficaz ou até prejudicial ao paciente. Vale ressaltar que raros são os estudos relacionados ao aparelho de \"veneno\" dos colubrídeos. Deste modo, tivemos como objetivo estudar as características anatômicas, morfológicas e ultra-estruturais da glândula de Duvernoy de seis espécies de colubrídeos opistóglifos. São eles, Philodryas olfersii e Philodryas patagoniensis da Tribo Philodryadini, Oxyrhopus guibei e Phimophis guerrini da Tribo Pseudoboini e Thamnodynastes strigatus e Tomodon dorsatus da Tribo Tachymenini. As glândulas de Duvernoy das espécies em questão foram analisadas macroscopicamente para descrição das características anatômicas. Foram então, fixadas em líquido de Bouin para posterior processamento histológico para análise morfológica e histoquímica. Para o estudo ultra-estrutural, as glândulas de Duvernoy foram fixadas em glutaraldeído 2,0% em tampão cacodilato 1,0M (pH 7,3) para posterior preparação de acordo com o protocolo pré-estabelecido. Os resultados obtidos mostraram que a referida glândula apresenta duas porções bem distintas, sendo a glândula supra-labial e a glândula de Duvernoy propriamente dita, as quais variam de forma e tamanho segundo a espécie. A glândula de Duvernoy é constituída basicamente por túbulos secretores e ductos excretores. As células dos túbulos secretores podem produzir substâncias de diferentes composições químicas, dependendo da espécie. Os resultados histoquímicos mostraram que a maioria das espécies analisadas apresenta uma glândula de natureza seromucosa, e apenas uma espécie teve a glândula de Duvernoy classificada como mucoserosa. Os grânulos de secreção presentes no citoplasma das células secretoras, observados nas eletromicrografias, corroboram os resultados histoquímicos, já que a eletrondensidade dos mesmos caracteriza a natureza das células. A função da glândula de Duvernoy está diretamente relacionada ao hábito alimentar destas serpentes e ao modo pelo qual subjugam as suas presas. As serpentes que apresentam a glândula de Duvernoy com características mucoserosas subjugam as suas presas por constricção. Já as espécies que possuem a glândula de Duvernoy com natureza seromucosa utilizam o processo de envenenamento das presas para se alimentarem. Deste modo, as serpentes garantem o sucesso na imobilização das presas, impedindo que estas utilizem táticas defensivas perigosas à serpente, independente do uso da constricção

The colubrids have often been responsible for severe accidents, sometimes fatal for humans, all over the world. In the Hospital Vital Brazil of the Institute Butantan, in São Paulo, 40% of the snakebite registered is caused by serpents that are considered no poisonous. Among these, 97.3% belong to Colubridae family with 54.5% presenting aglyphous dentition and 42.8%, opisthoglyphous dentition. However, some accidents that involve the opisthoglyphous colubrids can break out clinic manifestation similar to the botropic accident. This fact has caused many debates, because due to an erroneous diagnosis or to the gravity of the accident, very often it is administered the anti-botropic serum, which in many cases may be ineffective or even harmful for the patient. It is important to mention that rare are the studies related to the venon-delivery-system of the colubrids. Thus, we propose to study the anatomical, morphological, histochemical and ultra structural characteristics of the Duvernoy´s gland of six species of opisthoglyphous colubrids. They are Philodryas olfersii and Philodryas patagoniensis of Tribe Philodryadini, Oxyrhopus guibei and Phimophis guerrini of Tribe Pseudoboini and Thamnodynastes strigatus and Tomodon dorsatus of Tribe Tachymenini. The Duvernoy´s glands of the species in question were analyzed macroscopically for description of the anatomical characteristics. They were then fixed in Bouin´s liquid for posterior histological procedures for morphologic and histochemical analysis. For the ultra structural study, the Duvernoy´s glands were fixed in glutaraldehyde 2.0% in buffer cacodylate 1.0 M (pH 7.3) for further preparation according to the established protocol. The results showed that the above-mentioned gland presents two well distinct portions, the salivary supralabial gland and the Duvernoy´s gland itself, with diversified form and size according to the species. The Duvernoy´s gland is formed by secretory tubules and excretory ducts. The secretory tubules cells may produce substances of different chemical compositions according to the specie. The histochemical results showed that the majority of the analyzed species present a gland of seromucous type, and only one species has the Duvernoy´s gland classified as mucoserous. The secretion granules present in the cytoplasm of the secretory cells observed in the eletronmicrographics corroborate the histochemical results, since the electron density itself characterizes the cells. The function of the Duvernoy´s gland is directly related to the feeding habit of these serpents and to the way they subjugate preys. The serpents that present the Duvernoy´s gland with mucoserous characteristics subjugate their preys by constriction. On the other hand, the species that have the Duvernoy´s gland of seromucous type use the prey poisoning for feeding. Therefore, the serpents guarantee the success of the immobilization of preys, impeding them to use dangerous defensive tactics against the snake, independently of the use of the constriction