News & Media

Reminder to test pasture and hay for annual ryegrass toxicity

Released on

Released on:
Friday, 4. December 2020 - 9:45

Owners are reminded to have pasture and hay tested and to monitor stock daily to prevent annual ryegrass toxicity (ARGT) in horses and livestock.

Department of Primary Industries and Regional Development veterinarian Martin Matisons said annual ryegrass was often present in Western Australian pastures and hay and it was important for owners to have feed tested to prevent the disease in their animals.

“ARGT is a serious, usually fatal disease, which occurs when livestock, including horses, eat annual ryegrass seedheads infected with a toxin-producing bacterium,” Dr Matisons said.

“The toxin is cumulative so animals will not show signs of ARGT until they have consumed a toxic dose – this may take weeks depending on the amount of hay or pasture being consumed and the amount of toxin present in the seedheads.”

Signs of ARGT in sheep, cattle and horses include a clumsy or wobbly gait, and dullness followed by being unable to stand and death. Stress or movement worsens the disease signs.

Dr Matisons said two steps were key to reducing the risk of ARGT in stock: testing and monitoring.

“When buying hay, always ask for a commodity vendor declaration and a testing certificate that shows the hay sample tested is low risk for ARGT,” he said.

“However, owners should note that a low risk test result does not eliminate the risk of poisoning, as ARGT could be present in other untested parts of the bales.”

Feed suppliers are encouraged to test hay or chaff containing annual ryegrass for ARGT risk before they sell it.

Dr Matisons said it was also important to monitor livestock daily when on hay or pasture containing annual ryegrass, as affected animals could recover from ARGT if removed from the feed source early.

“It is always recommended to call a vet when animals show signs of illness or die suddenly to ensure a correct diagnosis, which will allow disease in other animals to be prevented,” he said.

“Subsidies may be available to assist with testing costs in some cases – your vet will be able to advise on this.”

More information is available at the department website on annual ryegrass toxicity and hay testing.

Media contacts:

Jodie Thomson, media liaison                        +61 (0)8 9368 3937