For the first time ever, a cat has been named the charity PDSA's Pet Slimmer of the Year. Puss Amber lost 1.2 kg - that's 17 per cent of her bodyweight!
This was the rather large Amber before her diet. Her owner said her cat now plays much more and no longer "waddles".
Second place also went to a cat! This is Socrates before his weight loss. He used to be more than double his ideal weight.
But now he's lost 14 per cent of his bodyweight and is a much happier cat.
Tara the Labrador was in joint third place. She lost 11 per cent of her bodyweight and now has "boundless energy," her owner said.
Here's before and after shots of Sasha the Staffordshire Bull Terrier, who came joint third. Apparently she's a "new dog" since she started her healthy eating programme.