For foals to be fit, healthy and have the best start in life, good nutrition for broodmares is key with the correct nutrients and feed required throughout the gestation period and after the youngster is born.
Owners need to consider two things which are maintaining the mare’s health while also ensuring there is support for the development and growth of the fetal foal.
In the early stages of a mare’s pregnancy the fetus grows slowly, therefore the nutritional requirements are very similar to those of a non-pregnant mare.
By the time the mare has been pregnant for five months, this is when the fetal growth rate starts to increase, which results in corresponding increases in the mare’s nutritional requirements.
Even at seven months, the fetus is still very small – less than two percent of the mare’s body weight and only approximately 10 to 15 per cent of its weight at birth.
Fetal growth is most rapid in late gestation and during the final trimester the fetal foal grows approximately one pound per day, this gain is about 70 to 75 per cent of its birth weight.
At this stage with the fetus growth accelerating at a great rate, the mare’s diet must be monitored closely with the nutrient level increased to ensure support for this growth, and the greater demand on the broodmare’s body.
In cases where a mare is undernourished during pregnancy, the mare will naturally use her own bodily stores to nourish the foetus. The mare will quickly lose condition, with her vital mineral stores becoming depleted.
When body reserves are low during late pregnancy and lactation this may result in reduced colostrum quality, poor milk production and reduce re-breeding success.
However also bear in mind that when broodmares become overweight this can lead to problems at foaling and also increase the risk of issues such as laminitis.
What should an owner do?
In an ideal situation when looking at condition mares should have a score of 3-3.5 out of 5 or 5-6 out of 9, depending on the system used. But bear in mind that during late gestation they may have less fat cover over the ribs due to the weight of the foetus and associated tissues.
When developing a feeding regime for the broodmare it should be put together with the aim of feeding as much forage as possible while limiting mixes and cubes to satisfy the mare’s energy needs.
During early to mid-gestation, good quality forage from pasture and hay as well as a vitamin/mineral supplement may be enough to meet the mare’s nutrient requirements.
Whilst ensuring the mare is receiving enough protein, energy and calories it is also important not to over-feed especially in the early stages of pregnancy as the mare can easily become overweight.
It is also essential to look at the quality of the feed and its effect on the diet and condition. A broodmare will generally enter the final trimester during the winter months, when understandably, forage will be of a lower quality.
Look for the best quality forage you can as this should be the basis of the feeding plan. Forage is most important when the mare’s diet is also feeding nutrients to the fetal foal as well as to her own body.
When looking at vitamins and minerals for the broodmare there are a number that are of special importance. These include calcium, magnesium and phosphorus.
For the healthy development of the fetus calcium and phosphorous are very important. It is recommended that in the final trimester, an increase of 85 per cent in the amount of calcium and a 100 per cent increase in the amount of phosphorus in the mare’s diet are vital in order to meet the fetal foal’s increased uptake of these minerals in late gestation.
Other essential trace minerals are iron, selenium, zinc, copper and manganese which are required for healthy bone and muscle development in the foal.
Some of the most commonly deficient vitamins for the broodmare in the final trimester are A and E, both of which are present in pasture and fresh hay, but it may also be necessary to add a supplement to the diet.
The mare will also have a requirement for protein during the gestation period as it is vital when it comes to the foal’s birth weight.
If protein is restricted during the last three months of pregnancy the newborn foal may not be able to absorb antibodies that are essential from the colostrum by 50%.
Contact the British Horse Feeds team for any feed advice.
Read more about our feeds here.