Cross fostering of low-birthweight piglets

The objective of the present study was to determine low-birthweight cross fostered piglets performance and suckling behaviour when grouped with high-birthweight or average-birthweight littermates in small or large litters. Within small litters either with high-or average-birthweight littermates, the low-birthweight piglets' behavioural variables did not differ (P>0.05) significantly. In contrast to small litters, low-birthweight piglets in large litters missed more nursing episodes and spent more time in "teat disputes" than their heavier littermates both in high-birthweight (P<0.01) and average-birthweight (P<0.05) litters. Relative weight of littermates had a significant effect on low-birthweight piglets mortality both in large litters with highP<0.001) and average-birthweight (P>0.05) littermates. Weight gain of piglets until day 3 postpartum was not significantly (P>0.05) affected by litter type and litter size, or the interaction of litter type and litter size. Low-birthweight piglets in small litters with high-or average-birthweight littermates had significantly higher 21-day weights compared to low-birthweight piglets-in large litters. High-birthweight (P<0.001) and average-birthweight piglets (P<0.01) gained significantly more by day 21 of lactation than low-birthweight piglets in large litters. The criteria measured are then mainly affected by litter size, and secondary by the weight of littermates in the large litters only. (C) 2004 Elsevier B.V. All rights reserved.