The effect of feeding â-mannanase in starter diets on nursery pig growth, feed intake and feed efficiency performance in a commercial wean-finish setting.

Abstract Text: Nine-hundred weanling pigs (initial BW = 7.59±0.012kg; 21d age) were used to evaluate the effect of a commercially available enzyme Hemicell HT®1.5x (HT) in corn-soybean meal-dried distillers grains with solubles diet on nursery pig growth performance. Pigs were allotted in a randomized complete block design into mixed gender pens, with 15 replicates per treatment, 20 pigs per pen, and fed 1 of 3 dietary treatments. Dietary treatments were: T1, Positive Control (3362, 3362, 3362, 3362 kcal/kg ME; by phase, respectively); T2, Negative Control (3362, 3252, 3252, 3252 kcal/kg ME; by phase, respectively); T3, T2+HT (0.08 MU/kg mannanase). Pigs were fed by budget in 3 dietary phases, 0.91, 2.27, 5.44 kg, respectively and phase 4 to conclusion. A common Phase 1 diet was fed to T1 & T2, T3 differed by enzyme inclusion.  Diets contained 2.5, 5, 10, 20% corn DDGS by phase, respectively. Pen BW and feed disappearance were recorded on d5, 12, 19, 26, and 43. BW on d5 was similar (P=0. 67) for all treatments. Period 2 (d5-12) ADG (319, 305, 313 g/d, T1-T3, respectively) was not significantly different (P=0.383). There was no significant difference (P=0.329) in Period 2 G:F (0.935, 0.899, 0.917, T1-T3, respectively). Period 3 (d12-19) ADG was increased (P<0.05) for T2 versus T3, while T1 was intermediate (0.989, 1.04, 0.951 g/d, T1-T3, respectively) and G:F increased (P<0.05) for T1 and T2 versus T3 (0.666, 0.677, 0.619, T1-T3, respectively). Period 4 (d19-26) ADG improved (P=0.017) (530, 514, 579 g/d, T1-T3, respectively) and G:F increased (P<0.05) (0.732, 0.720, 0.775, T1-T3, respectively) for T3 versus T1 and T2. Period 5 (d26-43) ADG tended to be increased (P= 0.060) for T1 versus T2, while T3 was intermediate (568, 508, 540 g/d, T1-T3, respectively). Period 5 G:F was increased (P<0.05) for T1 versus T2 and T3 (0.661, 0.607, 0.615, T1-T3, respectively). Final BW tended to be increased (P=0.078) for T3 versus T2, while T1 was intermediate (26.08, 25.21, 26.24 kg, T1-T3, respectively). Overall ADG (434, 413, 433 g/d, T1-T3, respectively) was not significantly different (P=0.254). Overall G:F was greater (P<0.05) for T1 versus T2, while T3 was intermediate (0.718, 0.691, 0.700, T1-T3, respectively). Supplementation of Hemicell HT®1.5x to nursery pigs resulted in intermediate overall feed conversion and tended to improve final body weight.

Keywords: swine, β-mannanase, Hemicell HT®1.5x