I am also pretty sure that they don't do the world's heaviest domestic cat for similar reasons. People will tend to overfeed a large cat to win the prize. This is not something that Guinness World Records want to promote as it is bad for business.
Here she is, the world's biggest domestic cat, "Magic", playing with Andreas, the son of Marti and Kathrin Stucki who raised them both:
Then we have the world's fattest cat. This is a cat I have not met. I wrote on this subject and so did a colleague of mine Finn Frode.
Here are the two articles:
Fattest Cat in the World
Clauz - World's Fattest Cat 1950
Then we have the world's longest cat, which is a Maine Coon. Maine Coons are more long than big although they are the biggest non-wildcat hybrid domestic cat breed in the world and the biggest registered by the Cat Fanciers' Asscociation (CFA), the best known cat association in the world.
To these landmark events we can now add the world's loudest cat! He is Smokey and I am glad to say that he is British and he is a silver mackerel tabby moggie (random bred). In fact he looks like a silver smoke tabby. His voice is louder that a Boeing 737 landing. I presume this is at max volume! On his website he is seen next to a decibel meter that shows 90.6 decibels. Apparently he purred at 67.7 decibels for the Guinness World Record.
Here he is:
He has a nice rather high pitched purr. It doesn't sound that intrusive but it is noticeable louder than any purr I have heard.
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