An outbreak of suspected poisoning of cattle by Dichapetalum sp. in Tanzania.

Between September and December 1995, 72 out of 476 cattle on 15 dairy farms in the Dar es Salaam region of Tanzania, died of suspected Dichapetalum poisoning. Following a drought and a resultant forage shortage, 12 of the farms had purchased hay from commercial farms in the Coast region, particularly from one seed and hay farm located about 60 km west of Dar es Salaam city. Following ingestion of the purchased hay, affected animals were acutely ill and their clinical signs included inappetence, dullness, high stepping gait, disinclination to move, jugular vein distension and gastrointestinal malfunctions. Fatal cases died suddenly after a short course of illness. Toxic plants identified as Dichapetalum mossambicense Engl. and D. stuhlmannii Engl. were found mixed in the hay. A diagnosis of Dichapetalum poisoning was made on the basis of history, clinical signs and post-mortem findings in fatal cases. On withdrawal of the contaminated hay, the outbreak subsided and deaths ceased. The findings of the investigation are discussed.