Authors : C.E. White , F.D. Lopez and L.R. McDowell
Abstract: A feeding trial and a balance trial were conducted to study the effects of adding virginiamycin and fat to grain sorghum-soybean meal (S-SBM) diets fed to swine. During the feeding trial, 96 crossbred pigs with an average initial bodyweight (BW) of 8.6 kg were assigned to groups of 24 each to be fed one of four S-SBM dietary treatments. Treatment one (T1) consisted of the basal S-SBM mixture and served as the experimental control diet. Treatment two (T2) was the control diet plus 11 ppm virginiamycin. In treatment three (T3), 3% of the S-SBM control diet was replaced with fat. Treatment four (T4) was both virginiamycin and added fat. Average daily gain (ADG), average daily feed intake (ADFI) and the ratio of feed consumed to BW gain (F:G) was not different (P>0.05) during the starting and growing periods (8.6-56.9 kg). However, during the finishing period (56.9-95.6 kg), and overall, the addition of 3% fat to T3 and T4 improved (P<0.05) F:G by lowering ADFI. Eight crossbred pigs with initial BW of 25.3 kg were used in a balance trial conducted within a 4x4 latin suare statistical design replicated twice to determine the nutrient utilization of the four diets used during the feeding trial. Additions of virginiamycin to T2 and T4 improved (P<0.05) intake, digestibility and retention of N. Apparent digestibility of nitrogen free extract (NFE) was also improved (P<0.05) in T2 containing virginiamycin but not when the antibiotic was combined with 3% fat in T4. Additions of fat to T3 and T4 increased (P<0.05) apparent digestibility of ether extract and crude fiber. Additions of virginiamycin (T2 and T4), fat (T3 and T4) or the combination of the two (T4) improved (P<.05) gross energy intake, DE and metabolizable energy (ME). Data from this experiment suggests that utilization of S-SBM diets fed swine was favorably influenced by additions of virginiamycin or fat, but the mode of action for these additives differed.
C.E. White , F.D. Lopez and L.R. McDowell , 2004. Effects of Virginiamycin and Fat on Utilization of Grain Sorghum Diets by Swine . Journal of Animal and Veterinary Advances, 3: 74-80.