Premium Nutrition For Broodmares & Young Growing Horses

By Gail Sramek BApplSc Agr – Consulting Nutritionist to Mitavite


The aim for all horse owners and stud managers is to produce a sound, healthy foal that is then grown out into a well-developed sound athlete. Correct care, management and feeding practices during pregnancy and foaling should be incorporated into a breeding program to ensure the young growing horse that is produced is in good health, is sound, is well developed and grown to reach its genetic potential. In addition to ensuring the health of the mare is maintained through all phases of pregnancy and her ability to care for her new foal and to be put back in foal in a timely manner after foaling are addressed.


Young Growing Horses

To produce a well-developed horse there is a balancing act between optimal growth and minimising skeletal problems that could affect the athletic ability and appearance of the horse. Poor management, genetics, exercise, hormones, conformation, growth and nutrition can interact together to contribute to developmental orthopedic disease (DOD), osteochondritis dissecans (OCD), physitis and angular limb deformities. We cannot help the horse if it has poor conformation or genetics, but it is imperative that a balanced feeding regime is provided to young growing horses to minimise growth related disorders to produce a sound elite athlete.


Contributing Factors to Bone Diseases in Young Horses:


The energy a young growing horse receives contributes to the growth rate of that horse. It is important that optimal growth rates are obtained, not maximum when growing out young growing horses. Maximum growth rate will only give the most rapid rate of gain. Feeding excess energy levels above 129% of maintenance have been shown to induce skeletal abnormalities in some horses. Ideally, optimal growth rate should be encouraged to contribute to athletic performance, longevity and soundness.


A young horse will attain 90% of its estimated mature height by the time it’s a yearling. Providing a ‘Good Quality Protein’ and the correct levels and ratios of minerals will support optimal skeletal development. A ‘Good Quality Protein’ will have the correct amount of protein, will contain the correct amount and level of amino acids and is well digested. Good Quality Protein needs to be provided in the diet for the skeletal muscle and bone to be correctly built and formed.


Bone diseases can affect the future career of young growing horses. If nutrition is compromised during the growth of the young horse or during pregnancy the strength and integrity of bone development can be reduced. It is important that the correct level of minerals are fed, not too much and not too little. Deficiencies in bone building minerals such as Vitamin K1, Calcium, Phosphorus, Copper and Zinc can contribute to bone diseases. Deficiencies in Copper can affect normal cartilage development, yet excess levels of Zinc affect Copper absorption and high levels of phosphorus can affect Calcium absorption. Too little Vitamin K1, Zinc, Calcium, Phosphorous and Copper or incorrect ratios of some minerals can cause poor bone development.


New research on the function of Vitamin K1 has found it has an integral role in the formation of strong, dense bone. A protein in the bone called oestocalcin needs Vitamin K1 to stick the major components of bone together, Collagen and Hydroxyapatite. Without adequate levels of Vitamin K1 the oestocalcin cannot bind the major components of the bone together to build bone with good structure and density. Research by Ray Biffin and his associates have shown that there has been a reduction in the incidence of bone diseases in young growing horses supplemented with Vitamin K1. The bone density of these trial horses has improved over the period of supplementation. We would strongly suggest that any diet for a young growing horse or pregnant mare should contain Vitamin K1 to ensure good bone density and geometry.



The best way to ensure your young growing horses are obtaining the nutrients they need at the correct levels is by feeding a highly digestible, well profiled, well formulated feed, such as Mitavite Breeda or Mitavite Promita.



Nutrition of the breeding mare is paramount to ensure she is healthy, has a good pregnancy rate, maintains her pregnancy, produces a strong, viable foal and can get back in foal in a timely manner.


Maximise Pregnancy Rates

The ability of the mare to ‘cycle’ greatly affects her reproductive performance. Cycling is affected by increased day length, a rise in temperature and the condition of the mare. Ideally mares should be on an increased plane of nutrition, making spring the ideal time for conception. If the mare is thin or overweight fertility can be affected. Mares that are maintained in a moderate to fleshy condition i.e condition score 6 (on a scale of 1-9) cycle earlier in the year, need fewer cycles to conceive, have a higher rate of pregnancy and have a higher likelihood to maintain pregnancy than thin mares.  A difficult foaling can affect the ability of the mare to conceive within the first two cycles after pregnancy, delaying the foaling date the following year.


Early Pregnancy

During early pregnancy, the mare has nutritional needs that are comparable to a spelling horse. Pasture alone will not meet the mares requirements so a well formulated concentrate such as Mitavite Breeda or if pastures are good, Mitavite Promita, should be fed depending on the pasture quality and quantity available.


Late Pregnancy

By the 7-8th month of pregnancy the foal has only grown to approximately 17% of its birth weight. In the last 3 months of pregnancy, over 75% of the growth of the foetus occurs and the nutritional demands in protein, macro minerals, micro minerals, energy and vitamins increase as foal can grow as much as 0.4-0.5kg per day. Ideally the pregnant mare should be kept in a moderate condition. The ribs should be covered but easily felt. Overweight and obese mares can have more complications during foaling and produce a lesser volume of milk after foaling. The foal has certain developmental periods of growth. The major periods for bone growth start to occur during the last trimester of pregnancy and it is important that all of the bone building nutrients such as Vitamin K1, Calcium, Phosphorous, Magnesium, Copper, Zinc and Manganese are available for optimal growth.



During the last trimester the appetite of the mare increases which is stimulated by the increased needs of the growing foetus for protein, vitamins, minerals and energy. As the foal grows it is taking up more room in the mare’s abdomen, restricting the digestive capacity of the mare. This coupled with the increased incidence of abdominal rupture and colics during the peri-foaling period increases the need to feed a well digested, steam-extruded, high nutrient dense feed to ensure the mare is obtaining optimal nutrients without overloading her digestive tract.


The mare’s milk is very low in trace minerals such as copper, manganese, zinc, selenium, iodine and iron. It is imperative that during late pregnancy the unborn foal has access to adequate levels of minerals, vitamins and protein so they can be used for bone growth and joint development. These nutrients need to be fed to the late pregnant mare so the foal can store them in his/her liver for use during the first three months of lactation, when the foal only has access to the mares milk.


One Month Before Foaling

Mares should be taken to the location of foaling and given a booster injection of tetanus toxoid four weeks before foaling. The injection allows the mare to be protected against tetanus, if tearing occurs during foaling, and the foal will receive colostrum that contains a source of antitoxin. By accustoming the mare to her foaling environment, she produces antibodies to fight the bacteria in the local environment, transferring her immunity in her colostrum to the newborn foal.



During the last month of pregnancy the mares udder will begin to swell and is given the term ‘bagging up’. Some mares can pre-lactate or ‘run their milk’, depleting precious supplies of colostrum that contain the protective antibodies foals need in their first milk. If the mare has large amounts of white, sticky milk down the sides of her hind legs there may be a need to give the foal a full dose of colostrum at birth. Your equine veterinarian will be able to suggest if this is needed and provide you with colostrum or a concentrated antibody drench.



During lactation the mare literally needs to eat enough for two. She needs to be fed a ration that will meet the protein, mineral and energy demands placed on her and produce enough milk to correctly feed her foal. The total milk yield is determined by the makeup of the mare, her condition and the consumption of energy, protein, nutrients and water during lactation. Therefore, the quality of the ration is paramount during lactation, ensuring it contains well digested energy sources, the best quality protein, amino acids and those all important bone building nutrients in a bioavailable form. Studies on protein levels have revealed a correlation between the quality of the protein and the growth rate of foals and the quantity of milk produced during the lactation. Lactating mares fed a diet low in minerals such as Calcium intensified bone demineralization, affecting the mares wellbeing. Alternatively, over feeding of nutrients to the mare may not flow through to the milk. Research in this area found over feeding of copper, zinc, calcium and phosphorous to the mare did not affect the concentrations of these nutrients in the milk. It is therefore important to get the balance right and minimise wastage by feeding a well profiled concentrate that will provide all the nutrients at the correct levels.


Pregnancy, foaling and lactation are an exciting time for stud managers and owners. Feeding pregnant and lactating mares and young growing horses a well formulated, highly digestible concentrate that contains the right amount of nutrients will ensure both the mare and the young growing horse are receiving premium nutrition to optimize the growth of the young horse and wellbeing and health of the mare.


For more information on feeding breeding mares and young growing horses contact Mitavite on 1800 025 487.