Sorghum 'ergot' feeding trials

High-priority research trials into the effect of ergot-infested sorghum in feedlot rations is under way at Queensland's Department of Primary Industries (QDPI), backed by growers through the GRDC.

The trials will help QDPI determine clear tolerances for ergot in sorghum and convince domestic and overseas grain buyers that it poses no significant risk, either to animal production or to human health at these tolerances.

The research may also have benefits for the dairy industry. Its blood-sampling component will allow an assessment of the risk of reduced milk production in cows fed infested grain.

The sorghum ergot poison belongs to the alkaloid family of commonly occurring substances, widely used in pharmaceuticals yet capable of such contradictory effects in animals and humans as lowering and raising blood pressure and body temperature.

The potential to affect body temperature is a major concern to the feedlot industry in the subtropics of Queensland and northern NSW, given major losses of lotfed cattle through heat stress in 1988.

Alarm bells rang in the $180 million sorghum industry earlier this year when a number of piggeries and dairy farms in central Queensland reported cases of feed refusal and reduced milk production in sows and cows being fed late-harvested grain heavily infested with ergot.

Investigation on these farms and preliminary feeding trials by the QDPI — involving pigs, poultry and beef cattle consuming an infested crop — confirmed the world's first proven instances of toxicity caused by sorghum ergot.

They also led QDPI to stipulate, in the Queensland Stockfood Regulations, a maximum level of 0.3 per cent sorghum ergot.

"Sorghum ergot has emerged rapidly as a potential problem for the grains industry around the world and Australia, as a result of its outbreak here, is leading the world in this research," said program leader Barry Blaney.

The trials are a cooperative effort involving also the University of Sydney and University of Queensland and an international information flow by email and via the Internet.

Mr Blaney said preliminary results will be presented at grower information workshops in March or April this year.

Program 2.3.1 Contact: Mr Barry Blaney 07 3362 9570

Region North