Intoxicação experimental por Metternichia princeps (Solanaceae) em coelhos

Abstract

Metternichia princeps, a tree that belongs to the Solanaceae family, occurs in the Atlantic Forest of Brazil, from the state of Rio de Janeiro to Bahia. In the county of Itaguaí, state of Rio de Janeiro, M. princeps was suspected to cause a lethal kidney disease in goats. The poisoning was experimentally reproduced in goats conϐirming the suspicion. Experiments were then performed in rabbits. Leaves of M. princeps were collected in the county of Itaguaí, where the poisoning in goats occurred. Eleven rabbits received the dried plant material, ten received the fresh plant and one rabbit served as control. The dehydrated leaves were ground and mixed with water. Initially the suspension was administered by stomach tube to nine rabbits and caused death of seven of them at doses from 0.125g/kg on. Two rabbits that got sick, but survived at doses of 0.0625g/kg and 0.125g/kg, received doses of 0.5 and 0.25g/kg respectively, two months later and died, indicating that no tolerance to the plant poisoning effects developed. Additionally the dried leaves administered six months after collection to two rabbits at doses of 0.5 and 1g/kg respectively, caused death only of the rabbit that received the dose of 1g/kg, indicating that the stored leaves lost toxicity. Fresh sprouts caused death in three of six rabbits at doses of 1.55g/kg to 3g/kg. Fresh mature leaves caused death in one of four rabbits at the dose of 2g/kg, what suggests that there is no difference in toxicity between mature leaves and sprouts. The dried leaves caused death of rabbits at smaller doses than fresh leaves, what can be explained by the way of administration of the plant; dried leaves were given within a few minutes, whilst fresh leaves were ingested during one or two days, a fact that may inϐluence absorption of the toxic principle. In all experiments with the dried and fresh leaves (sprouts and mature leaves) of M. princeps, liver and heart lesions predominated. The course of the poisoning was peracute to acute. The rabbits became apathetic with pale and cyanotic mucosae and cold ears; they fell down with struggling movements, vocalization and spaced breathing and died. At postmortem examination, the liver was pale with marked hepatic lobules; the other organs were congested and blood vessels were ingurgitated. The histopathological examination revealed as the more important changes in the liver, intense, especially centrilobular congestion, severe swelling of the hepatocytes, and foci of incipient necrosis of hepatocytes. In the heart, beside congestion, small groups of eosiophilic cardiac ϐibers, with nuclear picnosis and vacuolation were found. In the kidney, congestion and swelling of epithelial cells

Intoxicação por Metternichia princeps (Solanaceae) em caprinos no Estado da Bahia

“…A partir de casos espontâneos e experimentais, verificou-se que em caprinos, ovinos e bovinos predominam as alterações renais, enquanto que na reprodução experimental em coelhos observaram-se alterações cardíacas e hepáticas , Maran et al 2012. Em experimentos realizados em bovinos e ovinos o quadro clínico-patológico foi semelhante aos observados nos caprinos .…”

“…Casos de intoxicação espontânea só foram registrados em caprinos no Estado do Rio de Janeiro (Caldas et al 2011). Experimentalmente a intoxicação foi reproduzida em caprinos, bovinos, ovinos e coelhos , Maran et al 2012. Os principais sinais clí-nicos incluem dificuldade de locomoção, incapacidade de se manter em estação, prostração e decúbito, seguidos de morte.…”

“…Casos de intoxicação espontânea só foram registrados em caprinos no Estado do Rio de Janeiro (Caldas et al 2011). Experimentalmente a intoxicação foi reproduzida em caprinos, bovinos, ovinos e coelhos , Maran et al 2012 Out of eight goats three showed symptoms of poisoning and died; on two of them post-mortem examinations were performed. The main clinical signs were nasal mucous secretion, weight loss, diarrhea, lethargy, mild weakness, staggering gait, flexion of the fore and hind limbs, sternal recumbence, and lateral recumbence followed by death after approximately two days of clinical manifestations.…”

Intoxicação experimental por Metternichia princeps (Solanaceae) em ovinos e bovinos

“…Nos ovinos foi constatada adicionalmente lesão hepática, sob forma de uma tumefação difusa de todos hepatócitos (em todos menos no Ovino 5783), alteração que não foi veriϐicada nos bovinos. Esta tumefação dos hepatócitos foi observada em todos os coelhos experimentais (Maran et al 2012). Nos caprinos esta tumefação dos hepatócitos foi observada em 5 dos 10 casos naturais e em 6 dos 9 casos experimentais da intoxicação por M. princeps.…”

“…Sugeriu-se que o princípio tóxico de M. princeps responsável pelo quadro clínico-patológico da intoxicação em coelhos não seja o mesmo princípio responsável pela intoxicação nos caprinos, ou que os coelhos reagem de maneira diferente dos caprinos; nos coelhos predominam alterações cardíacas e hepáticas enquanto que em caprinos as lesões são renais. (Maran et al 2012) O presente estudo foi realizado para veriϐicar se ovinos e bovinos são sensíveis a intoxicação por M. princeps, qual a sua sensibilidade e qual é o quadro clínico-patológico.…”