GROVE - Four dogs rescued from an abandoned shack in rural Delaware County are thought to be part of puppy mill located on Grand Lake.

“This is the worst case of abuse I have ever seen, including puppy mill rescues,” said Carol Houghton, Heartland Lab Rescue intake coordinator.

Houghton said the Oklahoma City shelter received an email asking for help over the past weekend. The Labrador Retrievers were near death when they were found Saturday morning.

The malnourished dogs, three males and a female, were left with no food or water, and had limited access to shelter near the abandoned shack, she said.

“They appear to have been left there alone for weeks,” Houghton said.

The dogs, which are between 9-months-old and 4-years-old were taken to Oklahoma City for medical care. Houghton said.

“The older dogs should weigh 100 pounds, but they weighed around 40 to 45 pounds and the puppy weighs 25 pounds,” Houghton said.

All of the dogs are skin and bones and the 9-month-old male puppy is extremely sick, she said. Out of the group, the puppy got the least amount of food when it was available, Houghton said.

“The female has a diseased uterus from over-breeding and she's not even a year-old yet,” Houghton said.

Three of the Labs are yellow and one Lab is white, which is quite rare, she said.

White Labs sell for $350 to $500 and Yellow Labs sell for $150 to $250 each, Houghton said.

Because of the dogs' coloring Houghton thinks they are part of a puppy mill and because they were male, she thinks the dogs were dumped from a puppy mill.

“If the female dog wasn't breeding, they would kick her out too,” Houghton said.

Delaware County Sheriff Jay Blackfox said he has not received any reports of abused animals or an operation of an illegal puppy mill.

Oklahoma has the second highest number of puppy mills in the United States. A rural area is the perfect place to set up a puppy mill, Houghton said.