Kitten Within the first 2 days after birth, kittens acquire passive immunity from their mother’s milk. Milk within the first few days of parturition is called colostrum, and contains high concentrations of immunoglobulins. These include immunoglobulin A and immunoglobulin G which cross the intestinal barrier of the neonate. The immunoglobulins and growth factors found in the colostrum begin to establish and strengthen the weak immune system of the offspring. Kittens are able to chew solid food around 5–6 weeks after birth, and it is recommended that 30% of their diet should consist of solid food at this time. The kitten remains
Colostrum after calving. Livestock breeders commonly bank colostrum from their animals. Colostrum can be stored frozen but it does lose some of its inherent quality. Colostrum produced on a breeder's own premises is considered to be superior to colostrum from other sources, because it is produced by animals already exposed to (and, thus, making antibodies to) pathogens occurring on the premises. A German study reported that multiparous mares produced on average a liter (quart) of colostrum containing 70 grams of IgG. In most dairy cow herds, the calves are removed from their mothers soon after birth and fed colostrum from a