Toxicity of the leaves of Macrozamia spp. for cattle

Abstract

An account of feeding tests with three groups of cattle is given. One group was fed the leaves of Macrozamia pauli guilielmi, a second group mixture of leaves of M. douglasii and M. spiralis, and a third group the leaves of M. spiralis. Two distinct syndromes were produced. One was liver damage seen in animals in the group fed M. pauli guilielmi and then only when fresh green leaves were used. The other was an ataxia seen in animals in all three groups. This ataxia affected only the hindquarters and was characterised by a swaying to both left and right and a dropping of the rump. This was associated, in particular, with poorly controlled movements of the tibio-tarsal and metatarso-phalangeal articulations. No lesions to account for this disability were found. The toxicity of the leaves is evidently rapidly lowered by drying and withering on exposure to air.