The average (and ideal) litter for a queen seems to be about four kittens. Robinson’s Genetics for Cat Breeders and Veterinarians tells us that ‘statistics kept on pedigree cats indicate that most breeds tend to produce litters of about this size’.
The author makes an interesting observation which is why they used the word ‘ideal’. They say they ‘few females seem capable of nursing more than this number unaided, particularly if rapid growth of the kittens is to be expected’.
They suggest that when there is a large litter of kittens some of the kittens should be placed with queens who have small litters. Alternatively the kittens’ diet may be supplemented with milk in a special cat feeding bottle.
Cat breeders are advised to breed from females who are known to be good mothers as ‘the ability to suckle a complement of four young is not inherited’.
This is another interesting statement because I’d have thought that the ability is inherited. But if the mother fails in her task to suckle her kittens there must be an element of her character which makes her a bad mother and which overrides the natural and inherited desire and ability to suckle kittens. Or the circumstances affect her to the extent her natural instincts are overridden.
It can be added that a female cat can give birth to anywhere between one and ten kittens. The largest recorded litter from my source is 13 kittens (The Cat: History, Biology and Behaviour 1977 by M Beade).
Delivery times for a kitten to be born varies between one and fifty minutes. The interval between births is also very variable. It is said that newborn kittens have a special tolerance to a lack of oxygen as they can survive in the birth sac for a short while after birth (Wild Cats of the World).
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