Effect of different protein sources on growth and carcass traits in growing-finishing pigs

Crossbred gilts (n = 180) and barrows (n = 180) from the Louisiana State Un iversity (LSU) Agricultural Center and the University of Illinois (UI) were used to compare the effect of soybean meal in swine diets, relative to oth er protein sources, on growth performance and carcass traits of growing-fin ishing pigs. Four replications with five pigs each at each location were al lotted to nine dietary treatments: soybean meal control (SBM), crystalline AA (corn-AA), extruded soybeans (ESB), canola meal (CAN), peanut meal (PNT) , sunflower meal (SFLR), ground peas, meat and bone meal (MBM), and poultry by-product meal (PLTY). The diets were formulated to meet or exceed NRC nu trient requirements and to have equal Lys:ME according to dietary phase and sex. Corn was the grain source in all diets and the protein sources were t he sole source of supplemental protein in all diets except when AA were add ed to meet the requirement. Pigs (three per pen at each location) were kill ed at an average final BW of 114 kg in the LSU or UI Meat Science Laborator ies. Pigs fed SBM had greater (P < 0.05) ADG than pigs fed the corn-AA, CAN , SFLR, MBM, or PLTY and greater (P < 0.05) ADFI relative to pigs fed the c orn-AA, ESB, MBM, or PLTY. Gain:feed was decreased (P < 0.05) in pigs fed c orn-AA or SFLR but increased T < 0.05) in pigs fed ESB compared with pigs f ed the SBM diet. Loin muscle area was decreased (P < 0.05) in pigs fed the corn-AA or MBM diets compared with pigs fed the SBM diet. Tenth-rib backfat thickness was greater (P < 0.10) in pigs fed corn-AA, peas, or MBM than in those fed SBM. The NPPC percentage acceptable quality lean and kilograms o f lean were decreased (P < 0.10) in pigs fed corn-AA, peas, or MBM compared with those fed SBM. Results from this experiment suggest that pigs fed SBM have equal or better growth performance and carcass traits than pigs fed o ther protein sources.