ABOUT OVER-MATING

The aim of over-mating is to ensure that only in- calf heifers are used as replacements. In most beef herds, between 15% and 25% of cows are culled each year and must be replaced. The replacement rate is commonly 20%.

With over-mating, 20% to 30% more heifers than the number needed for replacement are mated and kept as replacement heifers. For example, if 20 replacements are needed for a 100- cow herd, 25 heifers are mated and the following year 20 are selected as replacements.