It appears that no domestic cat has beaten Himmy as the heaviest domestic cat on record. Dr Desmond Morris discusses this topic in his book Cat World published in 1996 and at that time Himmy held the world record for the heaviest domestic cat according to The Guinness Book of Records. I’ve checked the internet and he still appears to be the heaviest at 2020. He was a neutered tabby cat belonging to Thomas Vyse of Redlynch, Cairns, Queensland, Australia. He weighed in at 21.3 kg which is 46 pounds, 15.25 ounces. Himmy died of respiratory failure, aged 10, in 1986.
In 1991 an American magazine held a contest to see if there was an American cat who could outweigh Himmy, but they failed to find one. They did find a very heavy tabby cat called Spike living in Iowa but he only managed a relatively modest 37 pounds (16.8 kg). In 1992 the contest was repeated and the heaviest cat that they could come up with was a tomcat called Morris living in Kansas who could not even match the weight of Spike. Morris weighed 35 pounds.
Moving forward to 2012, the Metro newspaper has a photograph of a cat called Meow at the Santa Fe Animal Shelter and Humane Society of New Mexico. We don’t have a photograph of Himmy (correction a colleague of mine has produced a picture – see above and comments) but by way of a comparison in weight I have published on this page a photograph of Meow who weighed 18 Kg and who died of pulmonary failure on May 5, 2012. Eighteen kilograms is 39.7 pounds. This is about 6 pounds short of the weight of Himmy but his picture gives you an idea as to what Himmy must have looked like. To be clear, these heaviest of all domestic cats were not heavy because they were large in stature but because they were overfed and obese. I think nowadays people are far more reluctant to celebrate through records extemes in domestic cat anatomy if health is negatively affected as there is a concern that obesity might be encouraged.
Comment: the average weight of the domestic is about 10 pounds. Therefore Himmy was more than four times the average weight.
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