Science Explains Why Your Lab Is Always Hungry

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iStock

Dogs love food. Some love it more than others, and some of those are Labrador retrievers—the bottomless pits of the canine world. Scientists announced today that they’ve found a gene variant in labs that may explain that constant state of "Please Feed Me." The findings were published last year in the journal Cell Metabolism.

Dog obesity isn't something we talk about a lot, but there sure is a lot of it. In the U.S. and other wealthy countries, between 34 and 59 percent of dogs are overweight. And yes, fat dogs are cute, but they’re also in danger of some serious health problems. Canine obesity can cause heart disease, strain on a dog’s joints, diabetes, and can even shorten a dog’s lifespan.

Some breeds, like black labs, chocolate labs, and golden retrievers, are more obesity-prone than others. This is likely because, like many of us, they are highly motivated by food. Labs’ human companions learn quickly that a treat is the trick to getting their dog to behave. But those treats add up.

The domesticated dog, Canis familiaris, is a single species with a lot of variations. Great Danes and Chihuahuas are both dogs, but their bloodlines, and therefore their genes, are dramatically different. And all those differences within a single species make dog breeds a great resource for scientists studying genetics.

Researchers recruited nearly 400 adult Labrador participants. Of those dogs, 310 were pets recruited through an email invitation from the UK Kennel Club, and 80 were part of an assistance-dog breeding colony. Some of the dogs were fat, while others were not, but all of them were healthy, with no pre-existing conditions.

First, the dogs were weighed. Then the scientists collected drool samples from 33 of the dogs and sequenced the DNA within. The dogs’ owners then completed a survey about their labs’ eating habits.

As relatives, of course, the labs had a great deal of genetic material in common with each other and with other dog breeds. But they also had one gene variant that stood out: the deletion of 14 base pairs from a gene called pro-opiomelanocortin, or POMC. Previous studies of this POMC variant have shown a relationship with appetite and a feeling of fullness.

Each dog could have one copy of the POMC variant, two copies, or none. The more copies a dog had, the fatter and more food-motivated it was. And about 23 percent of labs are carrying at least one copy of the variant.

"People who live with Labradors often say they are obsessed by food, and that would fit with what we know about this genetic change," Cambridge University metabolism expert and lead author Eleanor Raffan said in a press statement.

Her co-author, Stephen O’Rahilly of the Wellcome Trust-Medical Research Council Institute of Science, says these findings have implications beyond kibble. "Common genetic variants affecting the POMC gene are associated with human body weight and there are even some rare obese people who lack a very similar part of the POMC gene to the one that is missing in the dogs. So further research in these obese Labradors may not only help the well-being of companion animals but also have important lessons for human health."

For the First Time Ever, a Mammal Has Been Declared Extinct Due to Climate Change

The Whitsunday Islands in Australia's Great Barrier Reef
The Whitsunday Islands in Australia's Great Barrier Reef
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An Australian rat-like rodent called the Bramble Cay melomys is the first known mammal wiped out by manmade climate change, The Hill reports. The now-extinct animal (Melomys rubicola) lived on the tiny, uninhabited island of Bramble Cay in the Great Barrier Reef. Despite exhaustive efforts to track down the melomys over seven years, no signs of the rodent could be found, and in 2016, Queensland’s state government declared the animal extinct.

These fears were confirmed when news broke this week that the national government had quietly changed the rodent’s classification from endangered to extinct. Meanwhile, the status of a fruit bat called the spectacled flying-fox was changed from vulnerable to endangered after a recent heatwave in north Queensland, which dealt another blow to a population that had already been cut in half over the last decade.

As for the Bramble Cay melomys, its demise can be attributed to rising sea levels, storm surges, and other weather events that have worsened due to climate change. According to The Revelator, the tides destroyed about 97 percent of the island’s vegetation, which was the rodent’s only food source.

Leeanne Enoch, Queensland's Minister for Environment and the Great Barrier Reef, told The Sydney Morning Herald that the latest animal extinction is evidence “we are living the real effects of climate change right now.”

In a 2018 study commissioned by the World Wildlife Fund, researchers found that up to half of the 80,000 plant and animal species that reside in 35 of the world’s most diverse areas could become extinct by the turn of the century because of climate change.

For some species, it’s already too late. A Hawaiian bird called the poo-uli (or black-faced honeycreeper) was declared extinct last year, largely due to diseases carried by mosquitoes, which thrive in warmer climates. For other endangered species in the U.S.—like the black-footed ferret, red wolf, and rusty patched bumble bee—there might still be time to step in and protect them.

[h/t The Hill]

A Fort Hood Mule With 12 Years of Army Experience Is Looking for a Forever Home

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iStock.com/PamWalker68

Attention, animal lovers: A mule in Fort Hood, Texas with more than a decade of U.S. Army experience is up for adoption. Tina the Army mule has been a part of the Fort Hood military base's 1st Cavalry Division Horse Detachment for most of her life, and now KWTX reports that she needs a place to spend her retirement.

Foaled in 1999, the Fort Hood 1st Cavalry adopted Tina in 2006. Since then, she has assisted in parades, weapons demonstrations, cavalry charges, and color guards for the division. She has experience pulling an M1878 Escort wagon in a harness as well as standing by calmly for ceremonies.

She worked as a draft mule until 2018, and now that she's retiring, Fort Hood officials are looking to find her a forever home. Tina has no health problems or dietary restrictions and enjoys eating Coastal Bermuda hay and pasture grass. Her sister Dolly, who died of bone cancer in 2018, was the only mule she's ever been paired with. Though Tina can perform light solo work, her new owners should be cautious about pairing her with another mule.

If you're interested in making Tina a part of your family, Fort Hood would like to hear from you. You can contact the current owners by emailing your request along with any questions to 1CDHorseCavalryDetachment@gmail.com by March 7. Once your inquiry is received, you'll be sent an application packet with instructions on how to proceed.

[h/t KWTX]

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