The colostrum or ‘first milk’ plays an important role in the development of the foal. Colostrum makes up the first 1.5 – 2.0 litres of milk, and is generated during the last month of lactation. It contains key antibodies, also known as immunoglobulin’s that are essential for developing the foal’s immune system. Mare’s milk will have on average, 26 grams of protein, 19 grams of fat and 61 grams of lactose per litre. It also provides hormones, enzymes and growth factors.
The milk is the main source of nutrients for the first three months, so it’s important to make sure the mares’ diet is properly balanced and her needs are met. A lactating mare has the same calorie requirement as a racehorse in training! Pasture does provide a lot of calories and protein, so if you mare foals when there is grass a plenty then two nutrients are taken care of. However grass is short on the minerals the foal will need for bone development. Using a vitamin and mineral balancer pellet will make sure the milk is nutritious and it won’t add weight to the mare.
Mare’s body condition influences what is in the mare’s milk. An overweight mare will have more fats and fewer proteins in her milk than a mare of healthy weight. Too much fat and not enough protein means the foal gets lots of calories and can grow fast, but there won’t be the necessary proteins for a strong structure to support the growth.