Gestation length can be defined as the period from the date of conception (i.e. when the female gets in calf) to when the subsequent calf is born. Shorter gestation length is generally associated with lighter birth weight, improved calving ease and improved re-breeding performance among dams. In addition, calves born with a shorter gestation length may be heavier at weaning due to more days of growth post-birth.
Interpreting Gestation Length EBVs
Gestation Length EBVs provide an estimate of genetic differences between animals in gestation length. Gestation Length EBVs are expressed in days.
Lower or more negative Gestation Length EBVs are considered to be more favourable. For example, a bull with a Gestation Length EBV of
–2 days would be expected to produce calves that are born earlier, and more easily, than a bull with a Gestation Length EBV of +2 days.
For more information regarding Gestation Length EBVs, please contact staff at your BREEDPLAN processing centre.