Location: Poisonous Plant ResearchTitle: Doença de depósito lisossomal induzida pelo consumo de Ipomoea verbascoidea (Convolvulaceae) em caprinos no semiárido de Pernambuco) Author
Submitted to: Pesquisa Veterinaria Brasileira
Publication Type: Peer reviewed journal
Publication Acceptance Date: 6/4/2013
Publication Date: 7/1/2013
Citation: Lima, D.D., Albuquerque, R.F., Rocha, B.P., Barros, M.E., Gardner, D.R., Medeiros, R.M., Correa-Riet, F., Mendonca, F.S. 2013. Doença de depósito lisossomal induzida pelo consumo de Ipomoea verbascoidea (Convolvulaceae) em caprinos no semiárido de Pernambuco. Pesquisa Veterinaria Brasileira. 33(7): 867-72. Interpretive Summary: In the Northeastern parts of Brazil some goats are found poisoned with clinical signs characteristic of lysosomal storage disease. The plant identified as Ipomoea verbascoidea is believed to be the source of the intoxication in the goats. The objective of this work was to describe the epidemiological, clinical and pathological aspects of both spontaneous poisonings from the field and those induced from experimental feeding protocol with Ipomoea verbascoidea. Plant material used in the feeding program was found to contain the indolizidine alkaloid swainsonine at a concentration of 0.02% dry weight. Swainsonine is the toxin present in locoweeds found in North America and is known for induction of lysosomal storage disease in animals. From the experiments it was found that experimental goats and those from field cases contained the same histological lesions and clinical signs of which are characteristic of those reported by swainsonine containing plants. It is concluded that I. verbascoidea is responsible for the field observed cases of poisoning and that animals consuming plant for 26-28 days after observation of the first clinical signs is enough to cause irreversible damage.
Technical Abstract: The aim of this paper was to reproduce the poisoning of Ipomoea verbascoidea in goats and describe the epidemiological, clinical and pathological aspects of spontaneous poisoning by this plant in Pernambuco. For this, we studied the epidemiology of the disease in seven mu¬nicipalities in the semiarid region of the State. Three spontaneously poisoned goats were exa¬mined and then euthanized and necropsied (Group I). To reproduce the disease, the dried le¬aves of I. verbascoidea containing 0.02% swainsonine were supplied at doses of 4g/kg (0.8mg swainsonine/kg) to two groups of three animals. The goats in Group II received daily doses of the plant during 40 days and were euthanized on the 41st day of the experiment. Goats from Group III received daily doses of the plant during 55 days and were euthanized on the 120th day of the experiment. Other three goats constituted the control group (Group IV). In experi-mental groups, the brain lesions were evaluated by histopathology; additionally the cerebellar lesions were evaluated by morphometry, by measuring the molecular layer thickness, the number of Purkinje cells and the area of the cell bodies of these cells. The main clinical signs and microscopic lesions in goats poisoned were similar to those reported by swainsonine con¬taining plants. In goats of GII and GIII, the first nervous signs were observed between 22th and 29th days; clinically, the disease developed by these animals was similar to the spontaneous cases. The goats of GIII did not recover from the neurologic signs. These results show that the consumption of the plant by 26-28 days after observation of the first clinical signs is enough to cause irreversible damage. By morphometric analysis, the molecular layer of the cerebellum of the goats of Group I and III were thinner than those of goats in the control group, and Purkinje neurons were atrophic. It is suggested that these changes are responsible for the neurological picture observed in goats that stop eating the plant and have sequelae of poisoning.