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草业学报 ›› 2023, Vol. 32 ›› Issue (11): 119-129.DOI: 10.11686/cyxb2022494

• 研究论文 • 上一篇    

燕麦干草不同饲喂水平对牦牛日增重、血液生理生化指标及瘤胃发酵参数的影响

吴刀知才让1(), 裴成芳2, 马志远3, 刘红山1, 曹旭亮1, 刘虎1, 周建伟1()   

  1. 1.兰州大学草地农业科技学院,草种创新与草地农业生态系统全国重点实验室,甘肃 兰州 730000
    2.武威市天祝藏族自治县畜牧技术推广站,甘肃 武威 733200
    3.兰州大学生态学院,甘肃 兰州 730000
  • 收稿日期:2022-12-22 修回日期:2023-03-14 出版日期:2023-11-20 发布日期:2023-09-27
  • 通讯作者: 周建伟
  • 作者简介:E-mail: zhoujw@lzu.edu.cn
    吴刀知才让(1996-),男,藏族,甘肃卓尼人,在读硕士。E-mail: wudzhcr21@lzu.edu.cn
  • 基金资助:
    甘肃省重点研发计划国际科技合作类(21YF5WA117)

Effect of feed level of oat hay on average daily gain, blood physiological and biochemical indexes, and rumen fermentation parameters in yaks

Dao zhi cai rang WU1(), Cheng-fang PEI2, Zhi-yuan MA3, Hong-shan LIU1, Xu-liang CAO1, Hu LIU1, Jian-wei ZHOU1()   

  1. 1.College of Pastoral Agriculture Science and Technology,Lanzhou University,State Key Laboratory of Herbage Improvement and Grassland Agro-Ecosystems,Lanzhou 730000,China
    2.Animal Husbandry Technology Promotion Station of Tianzhu Tibetan Autonomous County,Wuwei 733200,China
    3.College of Ecology,Lanzhou University,Lanzhou 730000,China
  • Received:2022-12-22 Revised:2023-03-14 Online:2023-11-20 Published:2023-09-27
  • Contact: Jian-wei ZHOU

摘要:

通过燕麦干草不同饲喂水平来模拟传统养殖模式下牦牛采食量季节性变化的生产现状,旨在探究其日增重、血液生理生化指标及瘤胃发酵参数对饲喂水平的响应规律,以期为青藏高原牦牛的科学养殖提供一定的理论依据与数据支撑。试验采用4×4拉丁方设计,选取3.5岁、体重[(203.0±6.0) kg]和体况相近的健康去势牦牛6头,额外的2头试验动物作为其中一列拉丁方序列的生物学重复。根据模拟放牧牦牛不同季节采食量变化情况将燕麦干草饲喂水平分别设置为0.45、0.60、0.75及0.90 VI(voluntary intake, 自由采食),进而开展饲养试验。结果表明:1)牦牛日增重(ADG)随着燕麦干草饲喂水平的升高而线性增加(P<0.001),利用ADG(Y)与代谢能(ME, X)摄入量可建立拟合方程Y=973X-513 (R2=0.727),并据此估测得到牦牛的能量维持需要量为0.527 MJ·kg-1·BW-0.75·d-1;2)随着燕麦干草饲喂水平的升高,血液中红细胞数(RBC)线性降低(P<0.05),而血小板数(PLT)线性增加(P=0.05),其余血液生理指标不受影响(P≥0.10);3)牦牛血清尿素氮(BUN)与生长激素(GH)浓度随着燕麦干草饲喂水平升高而线性增加(P<0.05),但葡萄糖(GLU)浓度却线性降低(P<0.05);同时,胰岛素(INS)浓度随饲喂水平升高而呈升高的趋势(P=0.091),但β-羟基丁酸(BHBA)却呈降低的趋势(P=0.063);4)随着燕麦干草饲喂水平的升高,瘤胃液总挥发性脂肪酸(TVFAs)、乙酸和丁酸浓度线性增加(P<0.05),pH线性降低(P<0.05),而丙酸具有上升的趋势(P=0.093)。以上研究结果表明,牦牛血液生理生化参数与瘤胃发酵性能均在不同程度上受牧草饲喂水平的影响,最终又决定了其生产效率的高低。在本试验条件下,根据估算的牦牛维持代谢能需要量,燕麦干草干物质采食量至少在50.7 g·kg-1·BW-0.75·d-1时,其才能达到保膘或增重之目的。

关键词: 牦牛, 饲喂水平, 血液参数, 日增重, 瘤胃发酵

Abstract:

This study was conducted to investigate the response of average daily gain, blood physiological, biochemical indexes and rumen fermentation parameters to different feeding levels of pelleted oat hay in yaks, in order to provide technical data for scientifically informed yak farming on the Qinghai-Tibetan Plateau. Six healthy castrated yaks [(203.0±6.0) kg], aged 3.5 years old, were selected for the experiment which used a 4×4 Latin square design. The two additional animals were considered as biological replicates for one of the Latin square sequences. Voluntary intake of each animal was determined in a 14-day pretrial test, then oat hay feeding levels were set at 0.45, 0.60, 0.75 and 0.90 VI (voluntary intake). It was found that: 1) The average daily gain (ADG) of the yaks increased linearly (P<0.001) with increase in oat hay feeding level. A regression equation ADG (g·day-1)=973 X-513 (R2=0.727) was determined where X denotes metabolic energy allowance [MJ·kg-1·BW-0.75·d-1] established based on the ADG (Y) and metabolic energy (ME, X) intakes in yaks, and the estimated body maintenance ME requirement was 0.527 MJ·kg-1·BW-0.75·d-1. 2) As the feed level of oat hay increased, the population of red blood cells was decreased linearly (P<0.05), while the population of platelets was increased linearly (P=0.05), and the other blood physiological indexes were not affected by feeding level treatments (P≥0.10). 3) With increase in the feed level of oat hay, serum concentrations of urea nitrogen and growth hormone increased linearly (P<0.05) while glucose concentration decreased linearly (P<0.05). Meanwhile, serum insulin concentration tended to increase (P=0.091) with feed intakes whereas β-hydroxybutyric acid level tended to decrease (P=0.063). 4) The concentrations of ruminal total volatile fatty acid, acetate and butyrate increased linearly (P<0.05) with increased oat hay feeding level in yaks, and propionate concentration tended to increase (P=0.093), accompanied with a decrease of ruminal pH (P<0.05). The above results showed that both blood physiological and biochemical indexes and rumen fermentation parameters in yaks were somewhat affected by the feeding level of forages, which in turn ultimately determined the growth performance. According to the maintenance ME requirement of yaks estimated in present study, the dry matter intake of oat hay should be greater than 50.7 g·kg-1·BW-0.75·d-1 in order for the animals to maintain their body weight or gain weight.

Key words: yak, feed level, blood indexes, average daily gain, rumen fermentation