'Most obese' chihuahua at SF's Muttville Dog Rescue loses astounding two-thirds body weight

SAN FRANCISCO (KGO) -- The second Friday of the year is National Quitters Day, the day when most of us give up on our New Year's resolutions. But a tiny dog in Vallejo is giving inspiration for us to never give up.

When Vallejo resident Amanda Tull met then seven-year-old chihuahua mix, Sox, it was love at first sight.

"I think so. She's pretty easy to love," Tull said with a laugh.

But little did Tull know, her precious pooch hadn't always been a ball of energy.

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"When I saw her pictures, I was really stunned," Tull said.

When Sox arrived at Muttville, a senior dog rescue in San Francisco, Sox was more accustomed to being carted around in a stroller than running around like she can today.

A Muttville employee can even be heard in a cell phone video saying, "This dog may be in the running for the most obese dog ever!"

The dog was even named Sweet Tomato, given her weight -- a robust 30 pounds.

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The nonprofit Association of Pet Obesity Prevention reports dogs like Sweet Tomato are not alone. Its 2022 Pet Obesity Prevalence Study showed nearly 60% of dogs being overweight and obese. That's about a 3% increase from 2018.

"She was a very, we say, a 'potato-y' dog -- big and chunky!" said "Mutt Manager" Jen Coudron.

Coudron explained how the senior owner, who fed the dog a steady diet of bacon and eggs, had fallen ill and could no longer care for a pet. So began Sweet Tomato's weight-loss journey.

Videos provided by Muttville showed the dog exercising and breathing heavily while walking on a treadmill and being doted on by those at the senior rescue center. One video, provided by the chihuahua's foster, shows the animal making a very focused effort at -- and successfully -- jumping onto a couch. Her foster can be heard exclaiming "Oh my God!" in delight.

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After about three months, Sweet Tomato dropped 10 pounds, a whopping one-third of her body weight!

By the time Tull adopted her a few months later, the stroller was long gone. Her chihuahua mix had shrunk to a cherry tomato size and was renamed "Sox."

"Now she can jump and chase the cats and all kinds of things," said a proud Tull.

Things were challenging for this former heavyweight, who was not accustomed to her new healthy diet and did not eat for several days. But by day four, she was getting used to her new lifestyle and relishing her meals.

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"I home cook all their food, rice or quinoa, vegetables, fruit and then either chicken or salmon, sometimes ground beef or pork or turkey." Says Tull.

Now at a svelte 10 pounds, Sox has attained her weight loss goals and is right where she needs to be.

"Her life has been given back." Says Tull, who points out a lack of teeth does not stop Sox from jumping onto her lap.

So while many of us are having a hard time sticking to our New Year's Resolutions, take a moment to think about little Sox.

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"I think what she provides is inspiration when you want to quit." Says Tull.

Sox and her new owner hope to live a long life.

Cheers to never giving up.

You can learn more about Muttville here.

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