Colostrum is the first secretion of the mammary gland at the termination of the gestation period and in the first day or at most into the second or early part of the third day of lactation.
It is thick, viscous yellow liquid and is heat coagulable.
It is a mixture of blood plasma and milk, is particularly valuable to newborn calves for its high concentration of immunoglobulins.
Colostrum provides about 580 – 700 kcal/L and is higher in protein and lower in casein, carbohydrate and fat than mature milk.
It usually also contains more vitamins than milk, depending on the vitamin status of the cow. Colostrum contains larger amount of B vitamins like thiamine, riboflavin and folic acid.
In addition, colostrum has higher concentration of sodium, potassium and chloride than more mature milk.
Secretory immunoglobulin A and lactoferrin are the primary proteins present colostrum, but other proteins present in mature milk not present. Heat coagulability of colostrum is due to presence of increased amounts of globulins and lactalbumins.
The concentration of mononuclear cells is higher in colostrum.
A trypsin-like inhibitor present in colostrum may help to preserve the immunoglobulins in the alimentary canal of new born by preventing hydrolysis.
It is important that the cow’s colostrum is consumed within the first day of life, preferably about 7kg for each calf, which is sufficient to provide about 400 g of immunoglobulin.
What are the contents of cow colostrum?
