A scare campaign linking dairy products to autism by animal activist group People for the Ethical Treatment of Animals has raised the ire of dairy farmers in WA.
It is understood the advertisement, which has gone viral across social media, was originally intended as a billboard campaign in the US.
WAFarmers dairy section president Phil Depiazzi said the claims were outlandish and served only to discredit PETA.
"The average consumer can see right through it; there are no linkages, there are no facts behind this scare campaign," he said.
Mr Depiazzi said he had never seen any scientific study that showed a link between dairy products and autism.
"Most people are smart enough to see that it's just a storm in a teacup and won't be changing their milk-drinking habits because of the extreme view of PETA," he said.
PETA Australia's campaign co-ordinator Claire Fryer said dumping dairy products (from a diet) was a healthy choice and saved mother cows from being repeatedly impregnated and forced to produce milk for humans after their calves have been taken away from them.
"Cows' milk might be the perfect food for baby cows but it might also be making kids sick," Ms Fryer said.
But Mr Depiazzi said it was in the best interest of farmers to look after and care for their animals.
"To suggest otherwise demonstrates that PETA has a total lack understanding of farmers and farming systems," Mr Depiazzi said.
He said PETA and other activist groups were "light on facts" and used "emotive speak" to prey on consumers.
"Nothing that PETA comes out with surprises me," he said.
"Milk is a nutritious food and they have no basis to their claims. They don't understand agriculture and it's extremely disappointing from a farmer's perspective."
A spokesman for Dairy Australia said the PETA campaign in question had been discredited and there was no reliable scientific data to support any of PETA's claims.
He said that in contrast to the PETA advert, milk and dairy products were highly nutritious and formed a core part of a balanced diet.
"Most Australians are under-consuming the recommended (two to four) servings of milk, cheese and yoghurt each day," he said.
"Nutritional advice from a health professional should be sought before changing a diet - particularly if considering eliminating a core food group from the diet of a child."
Ms Fryer said that while the billboard advert was not currently in use, the information on the campaign could still be found on the PETA website.
She said PETA's US affiliate had updated its website to reflect current terminology about autism.
"The website provides parents with potentially valuable information that researchers have backed up from many families' findings that a dairy-free diet can help kids with autism," Ms Fryer said.
"Dumping dairy products - the consumption of which has also been found to contribute to asthma, constipation, recurrent ear infections, iron deficiency, anaemia and even cancer - is a healthy choice that the late Benjamin Spock, author of the bestselling Baby and Child Care, recommended for all families."