Australian Cattle Veterinarians president Robert Bonanno told the Australian Veterinary Association annual national conference in Adelaide this week that acute bovine liver disease could appear in cattle rapidly with mortality rates able to reach 100 per cent.

"It comes on very quick," he said.

"Cattle might be normal when they're bought in for milking in the morning, then dead by the afternoon."

The condition is caused by a type of fungus that grows on the plant - rough dog's tail - and causes severe photosynthesis.

"Cattle that are going into paddocks that have not been grazed in spring and have lots of bulk grass can be at risk," he said.

"The hard thing about all of these diseases is that more funding and testing is needed."

Dr Bonanno said mortality rates could also be high in haemorrhagic bowel syndrome - up to 90pc. "The important thing is for diseases to be identified early, and for producers to call the vet as soon as possible," he said. Zinc toxicity was rarely seen, but hairy heel warts - often seen on dairy cattle - were an increasing challenge.

"With the wet weather over the past few months, conditions have been ideal for hairy heel warts to occur," he said.

"They are caused by the treponema species of bacteria and a manure and mud slurry can cause feet to become affected with this problem."