State government issues warning about dangers of summer weeds

THE Victorian government is warning farmers about the dangers of summer weeds in the south-west, following recent and sporadic rainfall.

Heliotrope, also known as potato weed, is one of the toxic weeds germinating.

Agriculture Victoria meat and wool livestock industry development officer Dr Hannah Manning said the weed flourished in degraded pastures after summer rain so the conditions had been perfect for growth.

“Heliotrope contains a toxin known as pyrrolizidine alkaloid that damages livestock’s liver, which is also the same toxin that is found in Paterson’s curse.

“Heliotrope is not tasty so stock tend to avoid it but if there is no other feed available, they will consume it.

“The damage that is done is cumulative, which means, the liver damage increases each time an animal eats heliotrope. This may lead to liver failure or impaired copper metabolism leading to a build-up of copper in the liver.

“All animals are susceptible to heliotrope poisoning.”

Signs of liver damage associated with heliotrope poisoning often occur soon after cattle and horses are exposed to it and large losses of stock occasionally occur.

Dr Manning said sheep were more affected by the chronic copper poisoning, which can result in sudden death when stored copper is suddenly released from the liver.

“This can happen well after sheep have been exposed to heliotrope.”

The control of heliotrope involves using a combination of pasture management, grazing management, cultivation, and chemical control, and farmers are encouraged to consult a pasture agronomist for advice.