184 Effects of phytogenic feed additives and Ractopamine HCl on growth performance and carcass characteristics in grow-finish pigs

Abstract

Abstract The objective of this experiment was to evaluate the effects of a phytogenic feed additive (PFA-F, Digestarom® Finish, BIOMIN America Inc.) on growth performance and carcass characteristics of grow-finish pigs compared to a control, two commercial PFA products (A and B), and a ractopamine feeding program. Two hundred pigs (Choice Genetics, BW = 24.88 ± 0.53 kg) were randomly allotted to 5 dietary treatments and fed diets based on 4 dietary phases. Dietary treatments consisted of: CON, a corn-soybean meal based diet; RAC, 4.5 ppm Ractopamine HCl was added into CON for the last 21 d; PFA-A (commercial product A) was added into CON when pigs reached 90 kg of BW; PFA-B (commercial product B) was added into CON from 75 kg of BW; PFA-F was added into CON from the beginning (25 kg of BW). Body weight and feed disappearance were recorded at the end of each phase, and carcass traits were measured at the end of the trial. Data were analyzed using the Mixed procedure of SAS. No differences were observed from phase 1 to phase 3 among the treatments. At the end of phase 4, RAC had a higher (P < 0.05) BW than the CON, PFA-A, or PFA-B (127.5 vs.123.1 or 121.5 kg); however, no difference between RAC and PFA-F in BW (127.5 vs.124.0 kg) was found. Pigs fed PFA-F had a higher (P < 0.05) hot carcass weight than those of fed CON or PFA-B (93.0 vs. 88.8 or 88.8 kg). No differences were found in lean percentage, fat depth, and loin depth among the treatments. In conclusion, PFA-F (Digestarom Finish) supplementation resulted in similar growth performance and hot carcass weight when compared to a Ractopamine feeding program during the grow-finish period, whereas either commercial product A or B had significantly lower performance than feeding Ractopamine.