Date Full Report Received02/16/2016
Date Abstract Report Received02/16/2016
Funded ByNational Pork Board
The objective of the study was to associate preweaning factors in gilt multiplication with the subsequent lifetime productivity of females in commercial sow herds. Sows were farrowed at two Smithfield Hog Production multiplication farms located in North Carolina between May 2013 and December 2013. From these sows, preweaning data was collected on 12,943 individual gilts. Preweaning factors of the gilt’s birth litter included total number born, number nursed, number weaned, litter sex ratio, cross-foster status (0 or 1), weaning age, birth dam parity and individual traits birth weight, weaning weight (adjusted to 21 d of age) and preweaning average daily gain. Gilts were traced from finishing facilities to commercial sow farms (n = 11) in eastern North Carolina. Of the 12,934 gilts individually tagged at birth, 10,613 (82.1%) survived to weaning and 6,249 (48.3%) eventually entered a commercial sow farm. When including all gilts tagged at birth in the analysis, a lower litter size at birth, gilts not cross-fostered and greater piglet birth weight, piglet weaning weight and preweaning average daily gain were associated with increased stayability to parity 1. Yet only a lower litter size at birth tended to increase stayability to parity 4. When including all gilts that were delivered to commercial sow farms, a greater weaning age, weaning weight and preweaning average daily gain were associated with more total pigs farrowed through 4 parities. Similarly, when including all gilts that were delivered to the commercial sow farms, a greater weaning age, weaning weight and preweaning average daily gain were associated with more total pigs produced per day of herd life through 4 parities. Results suggest gilt multiplication farms should not cross-foster gilts, increase weaning age to 25 days, increase piglet birth weight and preweaning average daily gain to enhance subsequent sow lifetime productivity.
– Gilts that were cross-fostered were 2.45% less likely to farrow a litter. Hence multiplication farms should only cross-foster males.
– Increasing weaning age by one day increased a gilt’s subsequent reproduction by 0.185 piglets per year. Hence, based on weaning ages observed in the current study, multiplication farms should increase weaning age to 25 days.
– Greater piglet birth weight increased the proportion of gilts that farrowed a litter. Hence strategies to improve piglet birth weight and/or reduce preweaning mortality will increase the efficiency of gilt production.
– Greater piglet preweaning growth improved the proportion of gilts that farrowed a litter and lifetime reproductive throughput. Hence management strategies that improve colostrum production, milk production and preweaning piglet growth should enhance subsequent lifetime productivity.