Colostrum is the first secretion produced by the udders after giving birth (it comes before milk). Bovine colostrum is a mixture of milk secretions and blood-serum components, such as IgG and other proteins, which build up in the mammary gland shortly before giving birth. Its composition gives it a high nutritional value and helps to protect newborns.
It is an important source of:
- proteins (in particular, IgG – antibodies);
- vitamins and minerals (magnesium, zinc, selenium);
- growth factors
| Density °/00 | Fat (g/kg) | Lactose (g/kg) | Total proteins (g/kg) | Casein (g/kg) | Vitamin A (UI/L ) | Vitamie E (mg/l) | Magnesium (g/kg) | Zinc (mg/kg) | Selenium (mg/kg) | |
|---|---|---|---|---|---|---|---|---|---|---|
| Bovine colostrum | 1,060 | 50 | 30 | 140 | 48 | 10 000 | 10 | 0,4 | 12 | 0,05 |
| Cows’ milk | 1,032 | 39 | 49 | 31 | 48 | 1 000 | 1 | 0,12 | 3,6 | 0,02 |
Colostrum requirements vary from species to species, depending on their physiology. For example, calves are born without antibodies, which is not true for other species. As a result, their only source of antibodies is colostrum. However, the intestine of the newborn calf is only permeable to antibodies for the first 24 hours of its life. Rapid administration of colostrum is the only way for the antibodies to travel from the intestine to the bloodstream. Ideally, newborn calves require around three to four litres of high-quality colostrum during the first 12 to 24 hours of their lives, which is approximately 200 g of antibodies.
Lambs and kids need 25 to 30 g of Ig during the first 12 to 24 hours of their lives.
For other species (pigs, domestic animals, etc.), their needs vary depending on their stage of life and the desired health benefit.