Efficacy of nosiheptide as a growth promotant for growing-finishing swine--a cooperative study.

A cooperative study involving 296 pigs was conducted at two experiment stations and at a commercial research farm to evaluate the efficacy of nosiheptide as a growth promotant for growing-finishing swine. At each station, five or six replicate pens of four or five pigs/pen were fed a fortified, corn-soybean meal basal diet with 0, 5.5, 11 or 22 ppm nosiheptide. Initial and final weights averaged 11 and 92 kg, respectively. Daily gain increased quadratically (623, 664, 669, 678 g/d; P less than .03) and feed/gain decreased quadratically (3.35, 3.24, 3.24, 3.28; P less than .02) with increasing level of nosiheptide. Breakpoint analysis indicated that gain plateaued at 6.8 ppm and feed/gain at 5.5 ppm of nosiheptide. Averaged across all levels of nosiheptide, gain and feed/gain during the growing phase (11 to 52 kg body weight) were improved by 13.1 and 7.6%, respectively, by feeding the antibiotic. For the entire growing-finishing period, gain was improved by 5.3% and feed/gain by 2.9% in pigs fed nosiheptide. Although there were large differences in gain and feed/gain, the responses to dietary treatments were similar among the three stations. The results indicate that nosiheptide is an effective growth-promoting agent for growing-finishing swine.