267 Evaluating the Interaction Between Nursery Diet Complexity and Pharmacological Zinc and Copper

Weaned pigs are typically fed complex, highly digestible diets to maximize feed intake and weight gain as they transition into the nursery. Further, pharmacological concentrations of zinc (Zn) and copper (Cu) are commonly fed to mitigate weaning-related diarrhea and performance reductions. A 2 x 2 factorial design was utilized to determine the effect of diet complexity with or without Zn and Cu. Four-hundred and thirty-two weaned pigs were randomly allotted to 48 pens (n = 9 pigs/pens). Pens were assigned to one of four diets: 1) A high soybean meal diet (Simple), 2) Simple + ZnCu, 3) Low soybean meal diet with spray-dried plasma, casein, and oats (Complex), and 4) Complex + ZnCu. Diets were fed in two 14 d phases. For ZnCu there were 3,000 and 2,000 ppm Zn in phase 1 and 2, and 200 ppm Cu in both phases. Bodyweight and feed intake were determined in phase 1 (d 0–14) and phase 2 (d 15–28). Pen was the experimental unit and all data were analyzed by diet complexity, pharmacological minerals and their interaction. No complexity by ZnCu interaction or diet complexity effects were observed in the 28 d study. However, ZnCu increased ADG (0.23 vs. 0.16 kg/day, P < 0.0001), ADFI (0.28 vs. 0.24 kg/d, P < 0.0001), and GF (0.80 vs. 0.69, P < 0.0001) in phase 1. In phase 2, ZnCu increased ADG by 9% (P = 0.008) and ADFI by 16% (P = 0.0001) compared to non-supplemented counterparts. Overall (0–28 d), ZnCu pigs had heavier end bodyweight (15.9 vs. 14.5 kg, P = 0.009), and greater ADFI (0.47 vs. 0.41 kg/d, P < 0.0001). In conclusion, diet complexity (high levels of soybean meal versus specialized protein alternatives) did not alter nursery performance. Irrespective of diet complexity, pharmacological Zn and Cu improved performance parameters.