暖季补饲精料对三江源区1岁放牧牦牛生长速度的影响
Effect of Supplementing Concentrate on Growth Speed of One-year-old Grazing Yak in Three-river Source Region

为探讨暖季三江源区1岁高原型放牧牦牛生长速度潜力，于2014-06-08在青海省玉树州称多县歇武镇牧业村三社对1岁放牧牦牛进行精料补饲对比试验。结果表明：试验36 d (7月14日)、80 d (8月27日)和120 d(10月6日)时，补饲组牦牛的平均体质量分别达到(75.79±10.93) kg、(101.71±11.20) kg和(117.54±13.07) kg，而对照组牦牛的体质量分别为(71.00±10.03) kg、(90.90±13.36) kg和(101.44±12.19) kg，且试验80 d时补饲组牦牛体质量显著高于对照组（P<0.05），120 d时补饲组牦牛体质量极显著高于对照组（P<0.01）；同时，夏初（6月8日-7月14日）、盛夏（7月14日-8月27日）和夏末（8月27日-10月6日）3个阶段的补饲组牦牛增质量和日均增质量均极显著高于对照组（P<0.01）；20项血清生化指标分析表明，除试验36 d时补饲组牦牛乳酸脱氢酶显著高于对照组（P<0.05）、血清磷极显著高于对照组（P<0.01）和80 d 时补饲组牦牛血清尿素氮极显著低于对照组（P<0.01）、血清镁显著低于对照组（P<0.05）外，其他指标均差异不显著（P>0.05）。可见，三江源区高原型牦牛在暖季“放牧+补饲精料”的饲养模式下，1岁牦牛平均日增质量为489 g，是传统全放牧方式下（295 g）的1.7倍，且对牦牛血清生化指标的影响不大，在产草量最高、牧草营养品质较好的暖季，适时合理的营养补饲能够有效挖掘出放牧牦牛具备的生长速度潜力。
To explore the effect of supplementary concentrate on growth speed of one-year-old plateau yak grazing in three-river source region.During warm season,supplementary test had been conducted in third clubs of husbandry village of Xiewu town of Tibetan Autonomous prefecture of Qinghai province on June 8, 2014. The result showed that the average body mass of yaks in experimental group was (75.79±10.93) kg,(101.71±11.20) kg and (117.54±13.07) kg on the 36th day (July 14), the 80th day (August 27) and the 120th day (October 6, 2014) respectively. However, the average body mass of yaks in control group was only (71.00±10.03) kg,(90.90±13.36) kg and (101.44±12.19) kg respectively.Treatment group was significantly heavier than control group on the 80th day（P<0.05）,while exactly heavier than control group on the 120th day（P<0.01）. At the same time, the body mass gain and average of daily body mass gain of treatment group were significantly higher than control group during the following three periods: early summer(from June 8 to July 14, 2014), midsummer(from July 14 to August 27, 2014) and late summer(from August 27 to October 6, 2014). Analysis of serum biochemical index was found that lactate dehydrogenase of treatment group was significantly higher than that of control group（P<0.05）, and serum P was also significantly higher than that of control group on July 14, 2014（P<0.01）. However, the blood urea nitrogen of experimental group was significantly（P<0.01）lower than control group and serum Mg significantly (P<0.05) lower than the control group on August 27, 2014. Other indexes was not significantly different (P>0.05). In conclusion, the average of daily body mass gain of one-year-old yak can reach 489 g by supplementary feeding concentrate during warm season, and is one point seven times than yak of traditional feeding mode. But there is not