Abstract

There are both clinical and sub-clinical effects on grazing ruminants that ingest the toxin sporidesmin produced by the fungus Pithomyces chartarum, with the clinical effects of the toxin giving rise to the colloquial name of the disease “facial eczema”. The sub-clinical effects of Facial Eczema (FE) have been documented and impact on most aspects of production from fertility through to growth. Data used to estimate the effects of the sporidesmin ingestion have ranged from natural exposure to high levels of sporidesmin in the outbreak in 1981 (Moore et al. 1990) through to differences in genetic selection lines and in trials where animals are artificially dosed with sporidesmin (Morris et al. 1991). Whilst the size of the impact does vary between studies, their overall conclusions are consistent, with decreased ewe fertility observed. In all studies, how the animal has tolerated (or not) the sporidesmin that it has been exposed to, is estimated through measuring serum gamma-glutamyl transferase (GGT) levels which have been shown to be a strong indicator of liver damage, the body organ most directly affected by the toxin (Towers & Stratton, 1978)...

Johnson, PL, HV Henderson, R Proffit, and NG Cullen

Proceedings of the New Zealand Society of Animal Production, Volume 77, Rotorua, 197-199, 2017