Dennis H. Sigler, Ph.D.
MFM Horse Nutrition Specialist
As spring is now upon us, it vital to consider the effects of nutrition on broodmare performance and foal development in utero and after birth. Obviously, energy (caloric) needs are very important. We know from research that energy intake and body condition have a profound effect on reproductive traits. Thin mares in a body condition score of less than 5 (those who’s ribs are showing) take longer to start normal cyclic activity in the spring, have lower conception rates, average more cycles per conception and fail to maintain their pregnancy more often than mares in good condition. Thin foaling mares will use all available energy reserves to produce adequate milk for the foal and will sacrifice their own body condition and reproductive activity to maintain milk production for the foal. This is why we recommend that mares go into the breeding or foaling season with a little excess condition. A body condition score of 6 – 6.5 is about right for foaling mares. That way if they lose some condition during the early lactation period, they will still be above a 5 at breeding time.
From the standpoint of foal nutrition, not only is adequate caloric intake crucial, but those nutrients most needed for bone development – protein and mineral also should be evaluated. Since we are trying to produce and grow equine athletes, skeletal structure is of utmost importance. In the pregnant broodmare, proper nutrition of the developing foal, in utero, is a key component of the total nutrition program for your horse herd. Scientific research has shown that mineral supplementation during the last 3 months of pregnancy can help reduce the incidence of developmental orthopedic disease in young horses.
Calcium and phosphorus are the major mineral components of skeletal tissue in the developing foal. Therefore, it is vital that adequate Ca and P be provided to the mare during late pregnancy and early lactation. The recommended daily intake of Ca and P for the mare in late pregnancy is 36 grams of Ca and 26 grams of P. The recommended ratio of Ca:P in the total ration needs to be between 1.4 and 2.0. Forages contain much more Ca than P and since both of these minerals are usually severely lacking in late fall and winter forages, supplementing with a high-quality mineral with a 1:1 Ca:P ratio is recommended throughout the year, but especially during these crucial spring and winter months.
MFM XL HORSE MINERAL or MFM 12:12 LIVESTOCK MINERAL can be provided free-choice to pastured horses to meet their Ca and P needs as well as trace mineral needs such as copper, zinc and manganese. Consumption should average between 3-5 ounces per day. If horses have not previously been on a mineral program, consumption will be much greater, even as much as 8 to 16 ounces, for several days until they catch up on their mineral needs.
Maintaining proper mineral balance, good quality protein intake and good body condition, are the keys for nutritional management of broodmares. By practicing good management during late gestation and early lactation, producers can assure optimum health and skeletal development of the new-born foal and optimum reproductive performance of the mare.