BLACK SOIL BLINDNESS - A NEW MYCOTOXICOSIS OF CATTLE GRAZING CORALLOCYTOSTROMA-INFECTED MITCHELL GRASS (ASTREBLA SPP)

A new, fatal mycotoxicosis of cattle has been recognised in north-west ern Australia. A feeding trial confirmed the toxicity of a previously unknown species of Corrallocytostroma that grows on Mitchell grass (As trebla spp). The disease has been colloquially named 'black soil blind ness' because its most prominent features are its confinement to pastu res on black soil, and blindness and death of affected animals. Over 5 00 cattle have died and considerable subclinical disease is present. A bove average wet season rainfall and extended growing seasons may expl ain the emergence of the fungus. The disease is important because catt le production in large areas of Australia utilise Mitchell grass pastu res.