Abstract:
The occurrence of annual ryegrass toxicity (ARGT) in sheep and cattle is reported for the first
time in South Africa. To date it has been diagnosed conclusively in South African Mutton Merino
sheep on a farm in the Caledon district and in cattle on 3 farms, 2 of which are situated in the Bredasdorp
district and 1 in the Ceres district. It is a neurological disease characterized by symptoms of
tremor, ataxia, intermittent epileptiform seizures, nystagmus, opisthotonus, abortions and high
mortality.
The history, clinical signs and experimental reproduction of the disease as well as the pathology
of 4 experimental and 10 natural cases in sheep and 2 in cattle are described.