PSVIII-4 Effect of coarse wheat bran and crude protein level in nursery diets without zinc oxide on pig performance

Abstract

Abstract A total of 355 pigs (DNA 200x400; initially 5.6 kg) were used to evaluate the effects of coarse wheat bran and crude protein (CP) level in diets without pharmacological levels of zinc oxide on nursery pig performance and fecal dry matter (DM%). Pigs were allotted to 1 of 6 treatments in a completely randomized design with 5 pigs per pen and 12 pens per treatment. Treatment diets were fed in two phases (d 0 to 7 and 7 to 21) followed by a common diet fed d 21 to 45. Treatments included a positive control diet with ZnO, negative control without ZnO, and negative control with 4% wheat bran and formulated to contain 21, 19.5, 18, or 16.5% CP. All diets contained 1.35% SID lysine except the 18 and 16.5% (1.25 and 1.20% lysine) CP diets. Data were analyzed using the lmer function from the lme4 package in R. During the experimental period, decreasing CP decreased (linear, P< 0.05) ADG, G:F, and d 21 BW, but increased (linear, P=0.005) fecal DM%. Pigs fed the diet containing ZnO had increased (P< 0.050) ADG, ADFI, and G:F compared to the negative control and diet with 21% CP and wheat bran. From d 21 to 45, pigs previously fed the 21% CP diet with wheat bran had increased (P< 0.05) ADG compared to the positive control. Fecal DM on d 45 and G:F increased (P< 0.05) for pigs fed the 21% CP, wheat bran diet and negative control compared to those fed the positive control. Overall, pigs fed low CP diets had decreased (P< 0.05) ADG while pigs fed the positive control had greater (P< 0.05) ADG compared to the negative control. Additional research is needed to determine if modifying low CP, wheat bran diets will elicit benefits of increased fecal DM% while maintaining growth performance.