In the natal den, soon after birth, kittens recognise their mother immediately via three senses: warmth, feel and smell. However, they probably have little idea what their mother is meant to smell like. The smell of their mother is not in their DNA. This has been proved when kittens suckled an artificial ‘mother’ which did not smell like a cat. It was imprinted on the kittens nonetheless.
The scientists did an experiment. They built a fake mother cat using fake fur through which they stuck fake nipples. Some of the nipples provided milk. Each teat was made to smell differently. Apparently two of the smells were cologne and oil of wintergreen. The kittens figured out which smells were associated with milk production.
That information comes from Dr Bradshaw. A study: “Olfactory guidance of nipple attachment and suckling in kittens of the domestic cat: Inborn and learned responses“, concluded that kittens are born with the skill and motivation to seek a teat on their mother’s belly (ventrum). They quickly learn that the scent of the teats are specific to their mother and they identify their nipple by smell.
The identification of the nipple is through odour not position and it occurs during the first few days after birth. This is confirmed by the fact that kittens identify their nipple not matter how their mother is lying down. A kitten will use the same nipple until they can leave the nest and feed independently of the mother at around 32 days old (source: “Suckling Behaviour in Kittens” – Author: R.F. Ewer).
Once they’ve claimed their nipple, it seems that they follow the scent trail that they’ve created in getting there when they return for a feed. This trail is made up of their own saliva and, it is believed, secretions from scent glands under their chins.
Also, kittens are flexible when bonding with their mothers who are part of a social group i.e. related. The mums share nests and pool their kittens. You can have three mothers sharing in the feeding of ten kittens, for example.
It seems too that under these sharing circumstances mums are relaxed about who to feed. If the kitten is in the mum’s nest it must be hers. This is why animal rescuers can successfully place an orphaned squirrel in the nest. The nursing mother accepts the baby squirrel as her offspring. You’ll see videos of this behavior on the internet. The same goes for slipping in an extra kitten even if he/she is much older.
Some mothers accept an entirely new batch of kittens placed with them after she has weaned her own. Provided she is well fed, no harm is done to the mother.
Pre-weaned kittens do not produce stress hormones. This protects them from a negative emotional connection and trauma in the nest which might otherwise deter them from feeding.
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