Effects of level of soybean meal and Yucca schidigera addition to diets on growth performance of nursery pigs

Abstract Text:  A total of 180 crossbred pigs (average BW = 6.1 kg) were used to determine the effects of addition of Yucca schidigera (Micro-Aid; Porterville, CA) to a soybean meal-based diet on growth performance of nursery pigs in a 43-d experiment. Pigs were weaned at 20 d of age and allotted to 1 of 3 treatments in a completely randomized design (5 barrows, 5 gilts/pen; 6 pens/trt). The three dietary treatments consisted of: 1) control diet (CNT) containing animal protein sources (plasma, fish meal), 2) a high soybean meal-based diet without animal protein sources (HSBM),  and 3) the HSBM-based diet plus 125 ppm of Micro-Aid (MA). Pigs were fed in four dietary phases.  During d 0-21, animal plasma and fish meal were replaced in the CNT diet with soybean meal.  Soybean meal was included at 30% in phases 1 (d 0-7), 2 (d 7-14), and 3 (d 14-21) for the HSBM and MA diets.  Soy protein concentrate, soybean oil, L-lysine HCl, DL-methionine, L-threonine, dicalcium phosphate, and limestone were added to the HSBM and MA diets to equalize ME, amino acid, Ca, and P concentrations. During phase 4 (d 21-43), due to decreasing use of animal protein sources, the concentration of soybean meal was similar across the three dietary treatments. Feed disappearance and BW were recorded to calculate ADG, ADFI, and G:F for d 0-14, 0-21, 21-43, and 0-43. For d 0-14, pigs fed CNT had greater (P < 0.02) ADG (222 vs 186 g/d), ADFI (281 vs 254 g/d), and G:F (0.79 vs 0.73) compared with pigs fed the HSBM diet. There was no difference (P > 0.10) in growth performance between pigs fed CNT and MA diets during d 0-14. Pigs fed MA tended to have greater (P < 0.10) ADG (209 vs 186 g/d) and greater (P < 0.04) G:F (0.78 vs 0.73) compared with pigs fed the HSBM diet during d 0-14. However, for d 0-21, 21-43, and 0-43, there were no differences (P > 0.10) among treatments. These results suggest pigs fed the HSBM diet from d 0-14 have decreased performance, but recover in the following phases, such that no differences in performance were noted at the end of the nursery phase. Addition of Micro-Aid tended to partially alleviate the negative effects of high soybean meal on growth performance during d 0-14 in the nursery. This work was partially supported by NPB SREE.

Keywords: pigs, soybean meal, Yucca schidigera