Ad libitum access to water should also be provided, even though some young horses don't drink water until they are weaned. Feeding Growing Horses Weaning of foals typically is done at about 6 months of age, although weaning at earlier ages is possible. Yearling and older horses should not require additional supplement if they have full access to good pasture. In winter months when forage growth has stopped, hay and grain mix should be provided in quantities and proportions calculated as above. The grain mix should be fortified with vitamins and minerals.
Commercial supplements are available along with mixing instructions for various grains.
Feeding pregnant and lactating mares Mares not carrying or nursing foals, and pregnant mares during the first 8 months of pregnancy can be fed in similar ways as non-working adult horses. Additional nutrient inputs are not required until the final 3 months of pregnancy, and during lactation. Body condition will dictate the level of feeding during these phases, but in general, energy needs will increase to about 1.2 X normal maintenance during the last 3 months of pregnancy and during lactation. If good graze is available, the mare will increase her intake to acquire the additional energy. If graze is not available, the diet should be formulated with additional concentrate to make up the additional energy.