Reproduction in the gilt. 2. The influence of gilt age at boar introduction on the attainment of puberty

Abstract

SUMMARY: Ten Landrace × (Landrace × Large White) young female pigs (gilts) were allocated to each of three growth rate treatments so that they attained 73 kg live weight at 135, 160 or 190 days of age. At 73 kg live weight the gilts were introduced to a vasectomized boar for 30 min each day, and were subsequently mated at the second oestrous period. The interval from boar introduction to puberty was 15·2 and 19·0 days respectively for gilts having first boar contact at 190 and 160 days of age, these intervals being significantly shorter (P<0·05) than the 34·3 days for the 135-day group. However, the mean ages at puberty of the 135- and 160-day groups (169·4 and 178·2 days respectively) were not significantly different but these gilts were significantly younger at puberty than the 190-day group (205·3 days). There were no significant differences between treatments for gilt live weight at puberty or first litter size.