A local producer made contact the about losing 7 month old weaners overnight. He had lost 15 out of 2000. They have been fed barley, lupins and a bit of triticale on a trail for weeks with no apparent change in feeding schedules or practices. The producer had noticed no problems until the previous day when they found 14 dead and one sick. They were fully vaccinated with 5 in 1 and drenched with Genesis in three months previously.
The sick animal was presented for examination and post-mortem.
The lamb was euthanised and necropsied with the following results:
Based on the history, clinical findings and post-mortem examination, grain poisoning is the most likely cause of the problem. Sloughing of the lining, associated with the rumen acidity is a common finding in grain overload.
On further questioning of the owner, these weaners were on a stubble paddock and being supplemented with grain by trail feeding. There has been rain over the past few days prior to feeding the grain. The rain may have prevented the weaners from getting out and feeding on the paddock feed, thus making them very hungry, with limited fibre to buffer the grain fed.
Advice was to start feeding out hay as well as the grain, as the stubble may have lost some of its value. Also to watch that the trail does not get too thick where a single animal can get in and gorge itself.