Energetic needs before total weaning

At four weeks of age, kittens eat around 10 gr of food per day and the major proportion of their daily requirement is contributed with breast milk. Around five weeks of age, they eat between 15 and 45 gr per day and increases gradually until they reach eight weeks old. This means that the nourishment of the kitten has to do with a considerable proportion of the amount of energy used by the cat and the kitties during the following stages of lactation.

The energetic average a kitten consumes , as a proportion of the whole energy used by the mother as her kittens, goes from 5% at week four in lactation, a 20% and close to a 30% during weeks 6 and 7 respectively.     

Energetic needs as soon as they have been weaned
In this stage, there is no real need to keep providing them with milk. As their digestive tract develop, the capacity to digest the lactose of the milk, gradually starts fading, even there exist cases of intolerance in some adult cats. If there is any desire to give them milk, there are special milks with small contents of lactose, nevertheless, they must always have water. Kittens have a small stomach, so it is better to feed them frequently with dense food rich in energy.

Unlike puppies, kittens must be fed using a free access system since they are not use to eating more than they have to. Kittens must weigh between 600 to 1000 gr at weaning. During that stage, male kittens are heavier than females and this is one characteristic that will maintain during all stages of their life.

Energetic needs come to the highest point around ten weeks of age, after this point, the energetic requirements for unit of corporal weight diminish gradually, though they still remain relatively high at least during the first six months while growing rapidly.