日粮尿素添加水平对秦川肉牛瘤胃发酵性能的影响

发布时间：2018-05-19 03:28

  本文选题：秦川肉牛 + 日粮　； 参考：《家畜生态学报》2017年04期

【摘要】：为研究秦川牛肉用补饲尿素(非蛋白氮)对瘤胃发酵环境的影响,试验选用3头饲养条件一致且装有瘤胃瘘管的秦川肉牛(公牛),正常饲粮预饲25d,随后每25d为一个饲养阶段,每个饲养阶段逐步对其日粮添加不同水平尿素0%(干物质百分比,对照组)、0.5%(A组)、1.0%(B组)、1.5%(C组)和2.0%(D组),每个饲养阶段中每5d采集一次瘤胃液,检测分析pH、氨态氮、微生物蛋白以及挥发性脂肪酸等瘤胃发酵关键参数。结果表明,随着尿素添加水平的提高,瘤胃液pH先下降后上升,B组pH最低,与其余各组差异显著(P0.05);随着尿素添加水平的提高,各处理组(除D组外)总挥发性脂肪酸量均显著高于对照组(P0.05),其中B组最高,与其余处理组差异显著(P0.05)。A组和B组挥发性脂肪酸与对照组均差异显著(P0.05),两处理组之间除总挥发性脂肪酸(TVFA)差异显著外(P0.05),其余四项挥发性脂肪酸指标均差异不显著(P0.05);随尿素添加水平的提高,四个处理组NH3-N含量均显著高于对照组(P0.05),其中D组显著高于其他处理组(P0.05);随着尿素添加水平的提高,微生物蛋白量除D组与对照组差异不显著(P0.05)外,其余三个处理组均高于对照组,B组最高,与其余处理组差异显著(P0.05)。秦川肉牛日粮中添加尿素可以有效提高瘤胃氨态氮、微生物蛋白、乙酸、丙酸等,且日粮中添加量1%(干物质百分比)为最适安全添加量,可提高秦川肉牛饲养效率,降低饲养成本。
[Abstract]:In order to study the effect of supplemental feeding of urea (non-protein nitrogen) on rumen fermentation environment, three Qinchuan beef cattle (bulls, normal diet, 25 days) with the same feeding conditions and rumen fistula were used in the experiment, followed by a feeding stage every 25 days. In each feeding stage, the diets were fed with different levels of urea (percentage of dry matter, the percentage of dry matter in group A and B) and group C and group D, respectively. Rumen fluid was collected every 5 days in each feeding stage to detect pH and ammonia nitrogen. Microbial protein and volatile fatty acids are the key parameters of rumen fermentation. The results showed that the pH of rumen fluid decreased first and then increased with the increase of urea level, and the pH of group B was the lowest, which was significantly different from that of other groups (P 0.05), and with the increase of urea addition level, the pH of group B was lower than that of other groups. The content of total volatile fatty acids in each treatment group (except group D) was significantly higher than that in the control group (P 0.05), and the highest in group B; There were significant differences between the two treatment groups in volatile fatty acids (VFA), except total volatile fatty acids (TVFA) and total volatile fatty acids (TVFAs), but there were no significant differences in the other four indexes of VFA between the two treatment groups. With the increase of urea level, The content of NH3-N in the four treatment groups was significantly higher than that in the control group (P 0.05), and the content of microbial protein in group D was significantly higher than that in other treatment groups (P 0.05), and with the increase of urea level, the amount of microbial protein in group D was not significantly different from that in control group (P 0.05). The other three treatment groups were all higher than the control group B the highest, and the other treatment group was significantly different from the other treatment group (P 0.05). The addition of urea to the diet of Qinchuan beef cattle could effectively improve the rumen ammonia nitrogen, microbial protein, acetic acid, propionic acid, etc. The optimum safe addition amount of urea in the diet was 1 (dry matter percentage), which could improve the feeding efficiency of Qinchuan beef cattle. Reduce the cost of feeding.
【作者单位】： 西北农林科技大学动物科技学院;国家肉牛改良中心;
【基金】：国家肉牛牦牛产业技术体系(CSRS-38) 陕西省科技统筹计划(2014KTZB02-02)
【分类号】：S823.5
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本文编号：1908533