Sheep and Goat Science Commons^™

Annual Ryegrass Toxicity Research Update, A G P Brown, P. Vogal

Journal of the Department of Agriculture, Western Australia, Series 4

Annual ryegrass toxicity (ARGT) is a complex disease that kills sheep and cattle grazing pastures which contain infected ryegrass. The disease results when a nematode (Anguina agrostis) and a batcerium (Corynebacterium sp.) invade annual ryegrass and cause the seed heads to become toxic as the grass dries off.

The bacterium produces a complex toxin of 18 glycolipid compounds or corynetoxins which have been found to be virtually identical to the antibiotic tunicamycin.

Control Strategies For Annual Ryegrass Toxicity, W J. Burdass

Journal of the Department of Agriculture, Western Australia, Series 4

In 982-83, annual ryegrass tocicity (ARGT) was estimated to have cost Western Australian sheep farmers between $7 and $8 million in total economic losses.

The disease can severely disrupt farming operations. Sheep must be checked daily and if affected moved to a 'safe' paddock. The availability of paddock feed is reduced, as is stock carrying capacity. Worry about the possibility of dramatic stock losses, and uncertainty about what decisions to make, are all stressful.

Stock losses from ARGT can be minimised by the use of selective herbicides to control ryegrass in pastures and crops. This breaks the disease cycle - …