Variation in individual piglet birth weights in a Large White × Landrace sow herd
Within-litter birth weight variation in pigs is increasingly becoming important in influencing the profitability of pig enterprises. The objective of the study was to characterize within-litter birth weight variation in piglets from Large White × Landrace sows. The study was conducted using records from 1 768 litters collected between January 1998 and September 2010 from a pig herd in South Africa. The number of piglets born alive (NBA) ranged from three to 18. The mean within-litter birth weight coefficient of variation (CVBWT) was 17.6% and ranged from 0.47% to 50.7%. The distribution of CVBWT in the herd was positively skewed. CVBWT increased as NBA increased. Multiparous sows farrowed litters with higher CVBWT than gilts. To enhance profitability of pig enterprises, the selection for increased NBA should be followed by selection for decreased CVBWT.
Keywords: Coefficient of variation, litter weight at birth, number of piglets born alive, parity