0
No gender × BP interactions were observed (P > 0.30) for any of the growth performance and carcass responses. During the growing phase, G:F improved (P = 0.001) and ADG tended to increase (P = 0.07) as the BP level increased in the diet. The greatest improvements were achieved with the highest BP level containing 0.89% standardized ileal digestible Lys. Gilts had improved (P < 0.001) G:F from d 0 to 28 compared with barrows. During the finishing phase, BP levels did not affect (P > 0.05) growth performance which may have been confounded by a relatively long duration (60 d) of the finishing phase. Over the entire 88-d period, ADG and G:F improved (P < 0.02) as the dietary BP levels increased. Gilts had lower ADFI and improved G:F (P < 0.01) than barrows during the entire period. Carcass characteristics (yield, backfat depth, loin depth, lean percentage) and income over feed cost were not affected by feeding varied levels of BP.
These results suggest that today′s pigs with high lean potential respond to a higher BP than current recommendations.
NW Shelton, RD Goodband, MD Tokach, SS Dritz, JL Nelssen, JM DeRouchey, MS Redshaw, and JK Htoo, 2010. Journal of Animal Science, 88 (E-Suppl. 2):490.
