People ask why mother cats kill their kittens. Here are five possible reasons.
The first possible reason why a mother might kill one of her kittens is that she is conducting a ‘disease control system’. By killing and eating one of her kittens who is suffering from an infection due to a reduced resistance or hypothermia and inactivity, the mother eliminates the pathogen from the nest thereby protecting the remaining kittens. For the method to work the mother has to act fast to prevent a build-up of the pathogen in the sick kitten who is incubating the disease. The reason why the mother eats the killed kitten is purely functional. It provides her with energy and energy is saved by not having to deposit the deceased kitten outside the nest. The query I have with this theory is that the mother is ingesting a virus. Does it threaten her health? Perhaps her digestive tract kills the virus.
It is suggested by the authors of The Domestic Cat: The Biology of its Behavior, that the mother might make a mistake in carrying out this kind of disease control methodology. This is because, as mentioned, she has to work fast and kill a diseased kitten early on. She has to detect signs of illness at an early stage which opens up the possibility of misdiagnosis. Perhaps she uses her sense of smell to detect an infection. But she has to diagnose a viral infection, which I’d suggest is difficult.
A second possibility is that the mother may detect a congenital defect (an inherited condition) in a kitten. Killing a deformed kitten does not stop the spread of an infectious disease but it does remove a kitten that would probably fail to reproduce when adult. This goes against the survival of the family and therefore the mother’s genes. Also in killing a deformed kitten the mother saves energy that would otherwise be used in maintaining that kitten. This means that more resources are available for the other kittens.
Another possible reason is having a litter which is larger than usual although I don’t fully understand how this can precipitate cannibalism. Perhaps it is a case of not having sufficient resources to feed all the kittens.
A further reason also turns on a mistake. She may eat and kill a kitten while eating her placenta. She may also accidentally kill a kitten while severing the umbilical cord.
Finally, there may be psychological factors causing the mother to feel insecure due to a perceived danger or threat to the mother’s survival. She may respond by killing her kittens. Note: the original photo on this page was of a mother and her 4 killed kittens. I was informed that the mother had killed them but I have doubts now so have replaced the image.
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