Joe A. Little

Longevity and maternal productivity of F1 crossbred landrace sows managed in two different gestation systems

Longevity and maternal productivity of 83 Duroc-Landrace (DL), 86 Hampshire-Landrace (HL) and 87 Yorkshire-Landrace (YL) sows were evaluated. Half of the sows of each cross were penned by cross in pasture lots during gestation. The remaining sows were confined in individual-sow gestation stalls. The 3 crosses of sows were bred in all possible combinations to 16 Duroc, 19 Hampshire and 19 Yorkshire boars. Litter sizes and weights at birth, 21 and 56 days were summed across 4 parities for each sow to form maternal productivity variables for each stage of production. The 256 sows farrowed 844 litters. A greater percentage of HL sows confined in gestation stalls completed 4 lactations than confined YL sows (88.0 vs 69.8%, P < 0.10). In the pasture gestation system, more total live pigs were produced at birth, 21 and 56 days in 4 parities by DL (40.0, 32.5, 30.9) and HL (38.2, 30.9, 30.2) sows, respectively, than by YL (31.1, 24.7, 24.3) sows (P < 0.10). In the pasture gestation system, DL (66.3, 168.9) and HL (56.5, 159.0) sows produced more kilograms of litter weight at birth (P < 0.10) and 21 days (P < 0.05), respectively, than YL (45.6, 124.8) sows. Confined HL (173.6) sows produced more kilograms of litter weight at 21 days in 4 parities than confined YL (143.1) sows (P < 0.10). Results from this study indicate that the breed of crossbred sows used in a production unit should be selected for the type of gestation system used on the farm.