AN ANIMAL welfare group says a Pyramid Hill puppy farm is one of many that are covertly operating across central Victoria.
More than 100 dogs were rescued from wire cages at the site in August and September.
RSPCA staff described the farm as one of the worst cases of animal cruelty in recent history.
The founder of Oscar’s Law campaign to abolish puppy farms, Debra Tranter, said the Pyramid Hill set-up was just the tip of the iceberg.
“It’s typical of many that are out there," she said.
"There are literally hundreds of puppy farms and backyard breeders in the state.
"There's no doubt there are more operating in central Victoria. They tend to be set up in very rural areas, where there are no neighbours in sight and people can't hear the dogs barking."
Ms Tranter said the Pyramid Hill farm was believed to be operating through a broker to sell the puppies to pet stores.
She said there were council permits required to breed dogs, but many breached the codes of practise.
"It's a huge issue," she said.
“I’m relieved that the dogs at Pyramid Hill are finally getting out. It's brilliant that they've shut it down... Realistically I don't think there are resources from RSPCA or councils to shut down all of them."
Ms Tranter has campaigned for more than 20 years to get people to choose alternatives in buying dogs, such as adopting or buying from an ethical breeder.
Between 2011 and 2012 she fought police and the Macedon Ranges Shire to gain care of a number of sick and malnourished dogs from a Macedon puppy farm.
She said the campaign, named after her new friend Oscar, was just the beginning.
"I think the solution is in the hands of the consumer," she said. "Every time puppy farms are mentioned, more people are educated and aware of what is actually going on."
The operator of the Pyramid Hill puppy farm is set to be prosecuted.