273 Longitudinal Investigation of Nutrient Intervention During Gilts Development on Sow Reproductive Performance and Longevity

Abstract

Abstract The objective of this study was to evaluate the dietary nutrient level and vitamin D source during gilt development on sow reproductive performance and longevity. Three groups of gilts (n = 60 in each group, PIC Camborough) were received at 9 weeks of age (average BW: 21.2 ± 0.67 kg) and assigned to one of four dietary treatments. Treatments comprised two levels of dietary nutrients (Adeq: optimal growing diets that exceed NRC 2012 recommendations or Low: moderate slow growing diet that SID lys and ME levels were gradually reduced by 0.03% and 0 kcal/kg, 0.15% and 146 kcal/kg, and 0.15% and 150 kcal/kg, respectively) and two sources of vitamin D [StD: 1653 IU cholecalciferol/kg or HyD: 500 IU cholecalciferol/kg + 50 mcg calcifediol (ROVIMIX HY-D DSM Nutritional Products North America)] during development phase 1 (22 to 57 kg), 2 (57 to 91 kg), and 3 (91 until breeding). Dietary nutrient level treatment was withdrawn during gestation and lactation stages, while sows remained on their vitamin D treatments through three reproduction cycles. Replacement gilts (n = 12 in each cycle) were handled and treated the same as the initial three groups of gilts and introduced to each group at the end of each cycle. Gilts fed Low diets had decreased ADG (P = 0.01), lighter BW (P < 0.01), increased ADFI (P < 0.01), and poorer feed efficiency during development (P < 0.01) when compared with gilts fed Adeq. Gilts fed Low were lighter (149.8 kg) than the Adeq (153.9 kg) fed gilts. Sows fed Low diets during their development had reduced number of stillborn (P < 0.01), 0.79 more pigs born alive (P = 0.10), and weaned a total of 238 more pigs than Adeq sows (2,127 vs 1,889, P < 0.01). Numerically greater lactation intake allowed sows developed using Low diets to have greater backfat at weaning compared with those developed using Adeq diets (weaning backfat: 13.0 vs 11.9 mm, P = 0.03). Gilts and sows fed HyD had significantly greater born alive litter weight (P = 0.03) due to numerical greater born alive (14.2 vs 13.47, P = 0.14) but average born alive piglet BW (P = 0.86) was not different. Piglets from sows fed HyD_Low diets had greater preweaning mortality compared with piglets from sows fed StD_Low diets because of greater number of pigs born alive observed in HyD_Low sows (1.323.vs.1,143, P = 0.02). Interestingly, a total of 5 sows that were culled due to lameness were all from the first cycle and StD treatment. Moreover, the percentage of sows rebred tended to be greater in sows fed HyD diets (P=0.08). These data indicate that the level of dietary nutrients fed during gilt's development and feeding HyD continuously from gilt development through subsequent reproductive phases, modulated reproductive performance.