Feeding PMU mares
According to the PMU Code of Practice, stallions must be put into the breeding pasture no sooner than June 1, and removed no later than the end of the first week in August.
With a gestation period of 11 months, foals will be born approximately May 1 to July 7. Mares come off the line about March 20-25.
Time from foaling until the beginning of the breeding season can be anywhere from zero to 60 days.
For many producers, the feeding program from the time mares come off the line in March until good pasture is available in June needs to be tuned up, especially when the mares have only 60 days to get back into foal.
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Mare condition at time of foaling and level of nutrition, particularly energy, are major factors that affect breeding performance.
While on the line, it is recommended mares be fed a ration averaging 62 percent total digestible nutrients on a dry matter basis. This is usually made up of mature forage plus approximately one pound of grain per 100 pounds (45 kilograms) of body weight.
When these mares are turned out, common practice is to feed them better quality hay but no grain. This reduces the mares’ energy intake just when it is most needed.
To provide adequate energy, good quality legume hay or very good quality grass/legume hay is required. Both types should be from an early cut. If hay can’t meet this quality standard, producers should supplement with grain.
Some producers are tempted to put mares out to pasture as soon as it turns green.
But until native pastures are approximately 15 centimetres (six inches) high, the forage is too high in water and too low in dry matter to provide adequate energy for a mare nursing a foal.
Keeping mares on a high level of energy after turning out, providing two to three ounces of mineral per day, and keeping them off pasture until the grass growth is adequate will pay handsome dividends in getting a high percentage of mares rebred.
– Animal Industry Nutrition Update
