环境温度、饲料、性别对肉鸡氨基酸表观消化率和氮、能代谢的影响

STUDIES ON THE EFFECTS OF ENVIRONMENTAL TEMPERATURES ON APPARENT AMINO ACID AVAILABILITY AND NITROGEN-ENERGY METABOLISM IN BROILERS

利用72只32日龄京白904肉仔鸡公母各半研究环境温度简称温度、饲料种类和鸡的性别对氨基酸表观消化率AAAA、氮能代谢的影响。试验采用3×2×2析因设计。试验鸡在8℃、24℃、30～32℃下处理14天,43日龄时,采用改进的真代谢能TME法测定3种温度下肉用公母鸡对玉米和豆粕的AAAA、代谢能及与氮代谢有关的指标。试验结果如下:饲料种类极显著地影响AAAAP<0.01。温度和性别对AAAA测值无显著影响P>0.05。内源干物质EDM排量不受温度的影响P>0.05。高温组表观代谢能AME显著高于低温组P<0.05,而常温组与高温组及低温组间差异不显著P>0.05。性别间AME无显著差异P>0.05。温度及性别对氮校正表观代谢能AMEn无显著影响P>0.05。尿酸FUA受温度影响极显著P<0.01。氮沉积率NR不受温度的影响P>0.05。氮平衡值NB受温度影响极显著P<0.01。

Seventy-two Beijing White 904 broilers,at thirty-two days of age,were used to study the effects of ambient temperature(Ta) on the apparent amino acid availability,the nitrogen and energy metabolism.The temperature controlling period lasted fourteen days.Three-factor factorial design was used in this study.At forty-three days of age,broilers(males and females)raised at three different temperatures(8℃,24℃,30～32℃)were force-fed two feedstuffs(maize and soybean meal(SBM))with″TME″method to determine the apparent amino acid availability,the apparent metabolizable energy(AME),apparent metabolizable energy with a nitrogen correction(AMEn) and other indices relative to nitrogen and energy metabolism.The results were as follows:apparent amino acid availability (AAAA) was affected by feedstuff significantly(P<0.01).Neither Ta nor sex had significant effect on AAAA(P>0.05).The endogenous dry matter(EDM)flow was not affected by Ta (P>0.05).The EDM flow of males was higher than that of females but it didn't reach significance (P>0.05).AME at 30～32℃ was higher than that at 8℃(P<0.05),AME at 8℃ had no difference with that at 24℃,so is AME at 30～32℃(P>0.05).Sex had no significant effect on AME(P>0.05).Neither Ta nor sex had significant effect on AMEn(P>0.05).The fecal uric acid(FUA%) of broilers force-fed with maize was lower than that of broilers force-fed with SBM,however,nitrogen retention(NR) was on the contrary.FUA(%) was affected by Ta significantly(P<0.01).FUA(%) at 30～32℃ was lower significantly(P<0.01) than at 8℃ or 24℃.There was no difference between FUA(%) at 8℃ and that at 24℃(P>0.05).NR wasn't affected by Ta(P>0.05).Sex had no effect on FUA(%) and NR(P>0.05).Nitrogen balance(NB) was affected by Ta(P<0.01).The NB at 8℃ was more negative than that at 24℃ or 32℃.