Himmy

Himmy was a tabby from Cairns in Queensland, Australia, who in 1986 was recorded at 21.3 kilograms — a little over 46 pounds — making him the heaviest domestic cat ever formally documented. He measured 96.5 centimetres from nose to tail tip and had a girth of 84 centimetres, and by the end of his life he had to be transported in a wheelbarrow.

He died of respiratory failure in 1986 at the age of ten. His weight was, straightforwardly, the cause: a cat carrying three times its healthy body mass places enormous strain on its heart, lungs, joints and liver, and feline obesity is strongly associated with diabetes mellitus, hepatic lipidosis, osteoarthritis and a shortened lifespan.

Himmy's record still stands in the sense that no heavier cat has been verified, but Guinness World Records made a decision after his death that has shaped the category ever since: they retired the heaviest-pet record entirely. The reasoning was that publicising such records created an incentive for owners to deliberately overfeed animals in pursuit of a certificate, and that the organisation did not want to be complicit in animal suffering. It was an early and unusually clear-sighted piece of welfare policy from a body better known for cataloguing curiosities.

Himmy is therefore remembered twice over — once as a genuine record holder, and once as the cat whose case ended the record. His name still appears in veterinary literature and in obesity-awareness campaigns, where he serves as a stark visual argument at a time when a substantial proportion of pet cats in developed countries are overweight or obese. Most vets would say the most useful thing about Himmy's story is that it is entirely preventable.