The Calving difficulty BV evaluates the suitability of a bull for use over yearling heifers. This trait has a low heritability, and therefore generally lower reliability. LIC assigns each bull to one of three groupings – Easy (<0.30), Average (between 0.30 and 7.10), Difficult (>7.10).
Short Gestation Length (SGL)
This trait is a breeding value to evaluate shorter gestation length to tighten calving patterns when used towards the end of the herd’s mating period. On average we would expect to shorten the gestation by three days using a bull with a SGL BV of –6.