Hufstedler G D, Greene L W
Texas A & M University System, College Station 77843, USA.
J Anim Sci. 1995 Dec;73(12):3785-8. doi: 10.2527/1995.73123785x.
Fourteen crossbred wether lambs (average BW, 28 kg +/- 2.3) were either implanted (12 mg of zeranol) or not implanted and group-fed an 86% concentrate diet for 21 d. Lambs were then moved to metabolism stalls and fed .8 kg/d for a 10-d stall adjustment followed by a 7-d total collection of feces and urine. Feed, feces and urine were analyzed for Ca, P, Mg, Zn, Mn, Cu, and N. Apparent absorption of Mn, Cu, and N, were similar for implanted and nonimplanted lambs. Zeranol did not affect (P > .10) the retention of Mn or Cu. Zeranol decreased fecal excretion of CA 22% (P < .01), P 27% (P < .05), Mg 11% (P < .03) and Zn 9% (P < .10). This increased apparent absorption of CA 88% (P < .01), P 193% ( P < .05), Mg 9% (P < .05) and Zn 45% (P < .10) in zeranol-treated lambs. Urinary excretion of all nutrients analyzed was similar for implanted and control lambs with the exception of N, which was reduced by 24% (P < .06) in implanted lambs. The amount of Ca, Mg, and Zn retained increased 98% (P < .01), 138% (P < .03), and 60% (P < .10), respectively, in implanted lambs compared with controls. These results indicate that zeranol improved N balance and enhanced the absorption and retention of Ca, P, Mg, and Zn in lambs.
14只杂种去势公羔羊（平均体重28千克±2.3），一部分被植入（12毫克玉米赤霉醇），另一部分未植入，两组均采用86%精料日粮进行21天的群饲。然后将羔羊转移至代谢笼，每天饲喂0.8千克，进行10天的代谢笼适应期，随后进行7天的粪便和尿液全收。对饲料、粪便和尿液进行钙、磷、镁、锌、锰、铜和氮的分析。植入和未植入玉米赤霉醇的羔羊对锰、铜和氮的表观吸收率相似。玉米赤霉醇对锰或铜的保留没有影响（P＞0.10）。玉米赤霉醇使钙的粪便排泄量降低了22%（P＜0.01），磷降低了27%（P＜0.05），镁降低了11%（P＜0.03），锌降低了9%（P＜0.10）。这使得玉米赤霉醇处理的羔羊钙的表观吸收率提高了88%（P＜0.01），磷提高了193%（P＜0.05），镁提高了9%（P＜0.05），锌提高了45%（P＜0.10）。除氮外，植入和对照羔羊所有分析营养素的尿排泄量相似，植入羔羊的氮排泄量减少了24%（P＜0.06）。与对照组相比，植入羔羊钙、镁和锌的保留量分别增加了98%（P＜0.01）、138%（P＜0.03）和60%（P＜0.10）。这些结果表明，玉米赤霉醇改善了羔羊的氮平衡，增强了钙、磷、镁和锌的吸收与保留。
