Natural and experimental poisoning of goats with the pyrrolizidine alkaloid-producing plant Crotalaria retusa L

Authors: MAIA, L - Veterinary Hospital, Federal University Of Campina Grande (UFCG); DE LUCENA, R - Veterinary Hospital, Federal University Of Campina Grande (UFCG); DA T NOBRE, V - Veterinary Hospital, Federal University Of Campina Grande (UFCG); DANTAS, A - Veterinary Hospital, Federal University Of Campina Grande (UFCG); Colegate, Steven; RIET-CORREA, F - Veterinary Hospital, Federal University Of Campina Grande (UFCG)

Submitted to: Journal of Veterinary Diagnostic Investigation
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 7/11/2013
Publication Date: 9/1/2013
Publication URL: http://handle.nal.usda.gov/10113/5491311
Citation: Maia, L.A., De Lucena, R.B., Da T Nobre, V.M., Dantas, A.F., Colegate, S.M., Riet-Correa, F. 2013. Natural and experimental poisoning of goats with the pyrrolizidine alkaloid-producing plant Crotalaria retusa L. Journal of Veterinary Diagnostic Investigation. 25(5):592-595.

Interpretive Summary: Crotalaria retusa L. (family Fabaceae; rattleweed) is a weed reported in the state of Paraíba, northeastern Brazil, as a cause of chronic poisoning in horses11 and acute poisoning in sheep.10,13 Cases of hepatic fibrosis associated with consumption of C. retusa have been reported in cattle,12 but could not be reproduced experimentally in this species by the continuous administration of low doses of monocrotaline (MCT), the principle dehydropyrrolizidine alkaloid (DHPA) produced by C. retusa.2 Lesions of chronic DHPA-related poisoning have been produced experimentally following administration of Jacobaea vulgaris (syn. Senecio jacobaea) to goats.6 However, in dosing experiments with Crotalaria saltiana3 and Heliotropium ovalifolium,1 the typical lesions of acute or chronic DHPA-related poisoning were not reported. In sheep in northeastern Brazil, the ingestion of seeds of C. retusa cause acute liver necrosis.12,13 In the current report, centrilobular liver necrosis is reported in goats that were ingesting C. retusa seed while occupying a paddock invaded by this plant. To demonstrate the association of the disease with the ingestion of C. retusa, the seeds of the plant were administered to experimental goats

Technical Abstract: Crotalaria retusa L. (rattleweed), estimated to contain about 4.96% monocrotaline (MCT) in the seed, was associated with a natural poisoning outbreak in goats. The poisoning was experimentally reproduced by the administration of C. retusa seeds containing approximately 4.49% of MCT. Thus, 1 of 3 goats given a single dose of 5 g/kg bodyweight (bw) of seeds (248 mg MCT/kg bw) and 2 goats given a single dose of 347 mg MCT/kg bw showed acute clinical signs and were euthanized 10-11 days after dosing. Clinical signs and gross and histologic lesions were characteristic of acute centrilobular liver necrosis.