What is the ideal age for a heifer for insemination?

Most heifers should be around 15 to 18 months of age to be receptive and be able to get bred. Of course this depends on the breed and the type of cattle. For dairy cattle, a farmer aims to have a heifer calve by 24 months, or two years of age. The gestation period for a cow is approximately the same as for humans - nine months. Hence, a farmer usually aims to inseminate a heifer at 15 months of age, but this also depends on the health and condition of the animal and whether is is physically fit to become pregnant.

For beef cattle, a heifer generally should be inseminated at around the same age. However, some breeds are quite late maturing, and will only be able to get bred at 18 to 22 months of age. Brahmans (or Zebu-type cattle) are late maturing, enough that only sees heifers getting bred or inseminated at this age.