Keano, from Plymouth, England, UK, was so overweight at 101.4 pounds, he could not roll over on his back before joining the People's Dispensary for Sick Animals (PDSA) scheme.
Five obese dogs and one cat completed PDSA's 100-day diet and fitness program, devised by vets.
The charity said canine obesity rose by 9% in the last year, which can cause potentially fatal conditions.
By Lindsay Beaton
As work continues on creating a new nutrition label that focuses on simplifying information for consumers, challenges remain.
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