Location: Poisonous Plant ResearchTitle: Alpha-mannosidosis in goats caused by the swainsonine-containing plant Ipomoea verbascoidea Author
Submitted to: Journal of Veterinary Diagnostic Investigation
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/1/2011
Publication Date: 1/1/2012
Publication URL: http://vdi.sagepub.com/content/24/1/90
Citation: Mendonca, F.S., Albuquerque, R.F., Evencio-Neto, J., Freitas, S.H., Doria, R.G., Boabaid, F.M., Driemeier, D., Gardner, D.R., Riet-Correa, F., Colodel, E.M. 2012. Alpha-mannosidosis in goats caused by the swainsonine-containing plant Ipomoea verbascoidea. Journal of Veterinary Diagnostic Investigation. 24(1): 90-5. Interpretive Summary: It has been observed that goats from some areas of northeastern Brazil have a disease affecting the nervous system. Upon examination of fields of farms with affected animals the plant Ipomoea verbascoidea was identified. This plant has been reported to contain the toxin known as swainsonine which can poisoning animals with symptoms of the nervous system and was therefore suspected as the cause of poisoning in the goats. The plant was collected and experimentally administered to 3 goats. The clinical signs and histologic lesions were found to be similar to those observed in reported field cases. Specifics of the histologic lesions are described along with chemical analysis of the plant that identified the toxin swainsonine as well as related compounds calystegine B1, B2 and C1.
Technical Abstract: A disease of the nervous system is reported in goats in the semiarid region of northeastern Brazil. Histological examination showed diffuse vacuolation of neurons and epithelial cells of the pancreas, thyroid, renal tubules, and liver. The swainsonine-containing plant Ipomoea verbascoidea was found on both farms where the goats originated. This plant was experimentally administered to 3 goats, inducing clinical signs and histologic lesions similar to those observed in spontaneous cases. On the lectin histochemical analysis, cerebellar cells and pancreatic acinar cells gave positive reactions to Triticum vulgaris agglutinin (WGA), succinylated Triticum vulgaris agglutinin (sWGA), Lens culinaris agglutinin (LCA), Canavalia ensiformis agglutinin (ConA), Pisum sativum agglutinin (PSA), Ricinus communis agglutinin (RCA 120), Arachis hypogaea agglutinin (PNA), and Phaseolus vulgaris erythroagglutinin (PHA-E) suggesting storage of a-fucose, a-D-mannose, a-Dglucose, ß-D-N-acetyl-glucosamine, N-acetyl-galactosamine, and acetyl-neuraminic acid. This pattern of lectin staining partially agrees with results previously reported for poisoning by swainsonine-containing plants. The chemical analysis of dried leaves of I. verbascoidea detected swainsonine (0.017%), calystegine B1(0.16%), calystegine B2(0.05%), and calystegine C1(0.34%). It is concluded that I. verbascoidea causes a-mannosidosis in goats.