When it comes to greedy canines, Labradors take the biscuit. Now, researchers have discovered why this breed is prone to gaining weight.
Scientists previously revealed that mutations in a gene called POMC (proopiomelanocortin) predispose dogs to obesity. This genetic variation is found in about one-quarter of Labrador retrievers and two-thirds of flat-coated retrievers, with the former being slightly more affected.
Two explanations for this association are currently emerging. This means that dogs with this mutation not only feel more hungry between meals, but also burn fewer calories at rest.
“This means these dogs are suffering a double whammy,” said study leader Dr Eleanor Laffan from the University of Cambridge.
But obesity in dogs is not a fait accompli.
“What we know is that there are [are] “There are many owners who manage their dogs carefully and keep them slim, and they do it with great effort,” Laffan said.
Writing in the journal Science Advances, Laffan and his colleagues describe an initial experiment in 36 adult Labradors that carried one, two, or no copies of the POMC mutation. .
The dogs, all fed a standard diet, were given breakfast, and three hours later researchers showed them a transparent box with a perforated lid and placed a sausage inside. The dog was then allowed access to the box.
Researchers found that dogs with the POMC mutation spent much less time resting and exploring the room and spent more time trying to get a bite to eat than dogs without the POMC mutation. did.
“The dogs with the mutation just had a stronger obsession with sausage,” Laffan said, adding that this suggested they were hungrier.
However, subsequent tests on 24 Labradors with one or no copies of the mutation revealed that this was not because they felt less full immediately after eating. Regardless of genetics, the dogs voluntarily ingested similarly large amounts of wet dog food (approximately 2 kg). Average – if offered a can every 20 minutes.
The researchers also analyzed the calories burned by 19 adult flat-coated retrievers at rest by measuring oxygen consumption and carbon dioxide production in specially modified kennels.
The researchers found that dogs with two copies of the mutation burned about 25% fewer calories than dogs without a copy. This is enough to significantly reduce the amount of food needed to maintain a healthy weight, the researchers say.
Although the human situation is more complex, Laffan said this study is a powerful example of how genes influence behavior around food.
“This is a message about the fact that obesity is not a choice,” she says. “This reflects an underlying desire to eat, driven by a combination of genes and environment.”
