Feeding Broodmares for Optimal Foal Health

NRM Breed To Succeed

Providing your broodmare with correct nutrition during pregnancy and lactation is important to the development and health of the foal. 

Broodmare Nutrition during Late Pregnancy

At seven months’ gestation, the foetal foal weighs only 20% of its birth weight.  This means that during the last four months of pregnancy the majority of the foetal growth occurs. At this point, the mare’s nutrient requirements increase significantly and adjustments should be made in the mare’s feeding program to ensure healthy development of the foetus. 

Digestible energy (DE) requirements only increase about 15 percent, however, protein, vitamin and mineral requirements increase to a greater extent. This is due to the foetal tissue being synthesised during this time being quite high in protein, calcium and phosphorus.  Trace mineral supplementation is also very important during this period because the foetus stores iron, zinc, copper, and manganese in its liver for use during the first few months after it is born. The foetus has developed this nutritional strategy of storing trace minerals during pregnancy because mare’s milk is quite low in these elements.

It is vital that mares receive correct vitamin and mineral supplementation during late pregnancy.  An example of this is the supplementation of copper.  New Zealand researchers have studied the effect of copper supplementation on the incidence of orthopaedic disease in foals.  When copper was given to pregnant mares, there was a significant reduction in physitis (inflammation of bone growth plates) scores of foals.  There was also a significantly lower incidence of articular cartilage lesions in foals from supplemented mares.  It appears that if the mare is not supplemented with copper in the final stages of pregnancy the negative effects on the foal cannot be reversed by supplementing the foal once it is born.

Selenium and vitamin E supplementation in late pregnancy has been shown to increase immunity in both the mare and foal. Vitamin A has also been found to be important to the late pregnant mare, with studies showing that growth rates of foals are significantly reduced when pasture is scarce and mares are maintained on hay without vitamin A supplementation. 

Maintaining an ideal body condition score is important for broodmares.  It is important that mares (like other classes of horses) are able to consume at least 1.5% of their body weight in forage per day.  While many broodmares will maintain weight well on pasture and hay, it is crucial that the additional vitamin and mineral requirements needed at this time are met through supplementary feeding. 

For good doers, a balancer pellet such as NRM Mare Balancer is a convenient way of meeting the increased protein, vitamin and mineral requirements without an increase in energy intake.  For mares who require additional calories to maintain condition as well as increased protein, vitamin and minerals above and beyond her roughage intake, a high quality concentrate such as NRM Evolve is ideal.  However, make sure you feed them at the correct daily rate to ensure nutrient requirements are met.  If your mare has any special dietary needs or metabolic conditions, it is best to contact an equine nutritionist for individual feeding advice. 

It is a good idea to supplement late pregnant and lactating mares with an omega 3 fatty acid supplement, preferably in the form of fish oil as these supply the preformed long chain omega 3 fatty acids EPA and DHA.  Studies have shown enhanced passive transfer of antibodies to foals which in turn have stronger immune systems as well as improved fertility, lowered incidence of uterine inflammation and decreased risk of abortion for pregnant mares fed omega 3 fatty acids.  KERx EO∙3 is a deodorised fish oil which provides a concentrated source of EPA and DHA omega 3 fatty acids.

 Broodmare Nutrition during Lactation

Once the foal is born, the mare’s nutritional requirements change.  The lactating mare requires approximately three times the amount of energy she would at maintenance.   Mares can produce milk at a rate of 3% of their body weight per day and require increases in the energy, protein, calcium and phosphorus during lactation.  It is important not to underfeed the lactating mare. 

Many mares cannot maintain their weight on forage only diets during lactation.  High quality supplementary hay should be fed to help meet the high energy demands placed on the mare at this time.  Calcium and phosphorus are the minerals that should be of primary concern during lactation, so lucerne hay is often the forage of choice due to its high calcium content. 

The quality of the protein supplied in the diet is important – high quality protein supports milk production and in turn supports foal growth.  An appropriate feed such as NRM Evolve can be fed to help meet both energy and other nutrient requirements.  It is important to follow intake rates recommended on the back of the bag, as feeding less than this will compromise nutrient intake.  If feeding less than the recommended amount, a high quality vitamin and mineral supplement or balancer pellet such as NRM Mare Balancer should be added to make up the shortfall.  It is advisable to speak with an equine nutritionist if you are concerned and they will be able to help you balance the diet.

After about three months of lactation, milk product begins to decline.  At this time, feed intake can be reduced to keep the mare in ideal body condition.  If you have any concerns about the body condition of the mare, it is best to consult an equine nutritionist for further advice.

For further information on feeding your broodmare to achieve optimum health of her and the development of the foal, please contact NRM on 0800 800 380 or via the website www.nrm.co.nz.