Answer: Many cats do prefer the test of milk to that of water, but this doesn’t mean there is any to provide milk. Milk consists mainly of water, though it is useful source of calcium and contains other nutrients. But it is supplies nothing that can not be obtained more cheaply from other foods. A cat receiving a good balanced diet has no nutrition requirement for milk, so that if it is provide at all it should be given as a treat after the cat has eaten its normal ration.
Perhaps surprisingly, many adult cats (including a high protection of oriental, breeds, particularly Siamese) are intolerant of cow’s milk and get severe diarrhea if they consume it. There are two possible reasons for this diarrhea. Certainly many cats have deficiency of the enzyme lactase needed to digest milk sugar. But some cats appear to be able to consume other types of milk (e.g. goat’s milk which also contains lactose) without getting diarrhea, and it is probable that these animals have an allergy to the protein in cow’s milk. Clearly, if this intolerance is suspected it would be wise not to feed any milk or any other dairy products to your cat. And it may in fact account for why so many Siamese are unwilling to drink milk.
Milk should not be regarded as a substitute for water and, regardless of whether milk is also provided, a bowl of fresh water should always be available so that the cat can satisfy its normal water requirements.
