Animal-welfare officials are calling on Montrealers to help them cope with more than 500 dogs seized in a weekend raid on a rural Quebec property that was home to an alleged puppy mill.

Rebecca Aidworth of Humane Society International Canada told the Montreal Gazette it needs supplies - everything from dog toys to bowls and bedding - as well as volunteers to help care for the dogs.

"We're calling on Montrealers to open up their hearts and give a desperately needed second chance to these dogs," Aidworth said.

Authorities descended on a kennel in Clarendon, 90 kilometres northwest of Ottawa, and removed some 525 dogs in what's termed the largest animal-cruelty case in Quebec history.

It took until late Saturday night to transport all the animals to an emergency centre, Aidworth said.

"It was quite the logistical effort," Aldworth said Sunday. "We're used to transporting animals in emergency situations but this was a very intensive, long operation."

Aidworth said both puppies and adult dogs were seized, numbering 30 breeds from chihuahuas to golden retrievers.

The dogs were denied basic needs and lacked socialization, Aidworth said. Veterinarians were also treating them for a variety of health conditions, including skin problems and breathing difficulties, she told the Gazette.

Quebec's Agriculture and Fisheries Department said the dogs will stay in their care until a judge decides if they should be returned to the kennel's owner or put up for adoption.

"Our primary goal is the successful prosecution of this case so we never have to return the dogs to this facility," Aldworth.

Paws "R" Us owner Charlene Labombard defended her treatment of the animals at her kennel. She said her family had a pig farm but turned to breeding dogs on the property 20 years ago after the pork market collapsed.

Puppies were kept in open pens in a barn and an addition to the farmhouse, the Gazette reported, while larger dogs were housed in plastic-lined pens. She said inspectors told her the dogs were being seized because of cobwebs on the ceiling, floors that weren't tiled and inadequate ventilation.

"I'm losing my livelihood and I'm very upset," she said. "It just breaks my heart."

She's not getting much public sympathy though.

"I'm smiling from ear to ear about the raid on the Quebec puppy mill," tweeted Donna Dempsie. "It's a good day for 400 dogs taken from hell."

It turns out Labombard has been fighting accusations for some time that she was running a puppy mill.

She successfully sued former customer Lorie Gordon for defamation and was awarded $14,000 in damages, though the case remains under appeal, according to the blog onebarkatatime.