Relationships between sow nutrition, milk yield, milk composition and piglet performance during lactation have been studied in numerous experiments. However, the subsequent effects of these pre-weaning factors on post-weaning piglet performance are less well studied. Commonly a growth check in piglets in response to weaning is noted, but to date it is unknown why some piglets do better than others in this period. The present experiment explored some of the pre-weaning factors that could explain the variability in piglet post-weaning growth.

The performance of piglets from 41 litters was monitored during a lactation period of 26 days. Litter size was standardised to 10 piglets, which were not offered creep food. Piglets were weighed individually on a weekly basis from farrowing to weaning at 26 days. Daily litter milk intake was estimated by a weigh-suckle-weigh technique in 24 litters on 4 occasions at 5 day intervals across lactation. On the day after each of these days, the composition of milk was determined from milk samples obtained by hand milking following oxytocin injection. Litter milk intake and composition of milk were used to calculate the mean daily piglet nutrient intakes during lactation. After weaning some piglets were sacrificed for the analysis of body composition and 310 piglets out of the 41 litters were penned in litter groups in controlled environment flat decks for two weeks to monitor daily group feed intakes and weekly individual growth rates.