低蛋白日粮调整TSAA水平对肉鸡生长和氮代谢的影响  

Effects of different TSAA levels in low protein diets on performance and nitrogen excretion in broilers

作　　者：段晓翔[1] 张丽明[1] 陈洪影 廖先东 周长海[1] 

机构地区：[1]吉林大学动物科学学院,吉林长春130062

出　　处：《饲料工业》2015年第2期10-14,共5页Feed Industry

基　　金：吉林省科技发展计划项目(国际科技合作项目[20120731];自然科学基金项目[20140101131JC])

摘　　要：试验旨在研究在玉米-豆粕型低蛋白日粮中添加不同含硫氨基酸水平（TSAA）对AA肉鸡生长和氮代谢影响。300只体重接近的8日龄AA肉鸡随机分为5个处理组,每个处理组设置4个重复。肉鸡的饲养按照NRC标准分为生长期（8-21日龄）和育肥期（22-42日龄）。对照组（前期CP23%、ME 13.20 MJ/kg、TSAA为0.90%;后期CP 20%、ME 13.45 MJ/kg、TSAA为0.72%）为正常蛋白、正常氨基酸水平,其余4个试验组为低蛋白组（前期CP 21%、ME 13.21 MJ/kg;后期CP 18%、ME13.42 MJ/kg）,粗蛋白含量比饲养标准降低2%。4个试验组TSAA水平分别为0.80%、0.90%、1.00%、1.10%（生长期）和0.62%、0.72%、0.82%、0.92%（育肥期）。结果显示：在试验结束时,0.92%的TSAA低蛋白日粮组肉鸡生长最快,平均体重达到2.55 kg,并且相比0.62%TSAA水平呈现显著性差异（P〈0.05）;在整个饲养阶段,低蛋白日粮组不同程度降低了肉鸡采食量,改善了料肉比（P〈0.05）,增加了饲料利用率;在42日龄时,不同处理组对肉鸡血清中Ca2＋和总蛋白无显著影响（P〉0.05）,低蛋白日粮组可以在不同程度上降低肉鸡尿素氮和尿酸的含量（P〈0.05）;在生长期,当低蛋白日粮中TSAA水平为0.80%时,可以显著降低肉鸡氮的消化率（P〈0.05）,但是对氮的排泄量无明显影响（P〉0.05）,在育肥期,低蛋白日粮各组可以降低肉鸡氮的排泄量（P〈0.05）,但对排泄率和消化率无明显影响（P〉0.05）。综上所述,低蛋白日粮调整TSAA水平不仅可以降低育肥期肉鸡氮的排泄,而且当TSAA水平为0.72%时,可以促进肉鸡生长,使肉鸡出栏重达到正常蛋白组,并且可以降低料肉比,增加饲料利用率。To investigate the effects of the TSAA levels in low protein corn-soybean diets on growthand nitrogen metabolism in broilers, a total of 300 8 days old AA broilers were randomly assigned tofive groups, each group has four replicates with 60 broilers. The raising term was divided into two peri-ods： starter（8-21 d） and finisher（22-42 d）. The diets in control group（starter CP 23%, ME 13.20 MJ/kg;finisher CP 20%, ME 13.45 MJ/kg） were formulated based on NRC（1994）, the level of TSAA and crudeprotein were met the standard, which meant that the level of TSAA were 0.90% and 0.72% in two peri-ods respectively. The other four groups were low protein diets（starter CP 21%, ME 13.21 MJ/kg; finish-er CP 18%, ME 13.42 MJ/kg）; the crude protein was decreased 2% lower. The level of TSAA were0.80%, 0.90%, 1.00% and 1.10% in starter dietsand 0.62%, 0.72%, 0.82% and 0.92% in finish-er diets. The results showed that the growth wasfastest in low protein diets with 0.92% TSAA,the average body weight was 2.55 kg significant-ly increased compared with the 0.62% TSAA di-ets（P〈0.05）; in whole periods, the low protein diets could decrease the feed intake and improve the FCR（P〈0.05） and the protein utilization in broil-ers; at 42 d, different diets could not affect the Ca2＋and TP in serum（P〉0.05）, however, the low pro-tein diets could decrease the serum UA and BUN in broilers（P〈0.05）. In starter, the digestibility of ni-trogen was decreased in low protein diets with low level TSAA in broilers（P〉0.05）, but it did not influence the nitrogen excretion（P〈0.05）; in finisher, the low protein diets could decrease the nitrogen ex-cretion（P〈0.05）, but the digestibility of nitrogen was not significant（P〈0.05）. In conclusion, the lowprotein diets could decrease the nitrogen excretion in fattening period, and the 0.72% may be the mod-est level of TSAA in low protein diets, as it can raise the growth, reduce the FCR and improve the pro-tein utilization in broilers.

关 键 词：低蛋白日粮 肉鸡 TSAA 氮代谢 

分 类 号：S816.7[农业科学—饲料科学]