目的 研究高海拔地区采用微贮干草饲喂白牦牛的育肥效果，指导养殖场（户）科学合理利用干草实现降本增效。 方法 选择3周岁左右、体质量285 kg左右、健康无病的天祝白牦牛36头，随机分为试验Ⅰ组（对照组）、试验Ⅱ组、试验Ⅲ组，每组12头。按照精料与粗料（4∶6）进行混合饲喂，在日均饲喂精饲料相同的情况下，试验Ⅰ组饲喂干草，Ⅱ组饲喂（50%干草+50%微贮干草），Ⅲ组饲喂微贮干草。经过90 d舍饲育肥试验，分别测定其生长性能、屠宰性能并计算经济效益。 结果 试验Ⅲ组较Ⅱ组、Ⅰ组平均日增质量分别提高0.05和0.09 kg，试验Ⅰ组、Ⅱ组和Ⅲ组料重比分别为11.03、10.97和10.65，在生长性能方面Ⅲ组与Ⅰ组差异显著；试验Ⅰ组、Ⅱ组和Ⅲ组屠宰率、净肉率、胴体产肉率和眼肌面积差异均不显著；平均增加1 kg体质量，试验Ⅲ组较Ⅱ组、Ⅰ组饲料总成本平均降低0.33、0.25元，平均效益分别提高0.40、0.46元。 结论 高海拔地区利用微贮干草饲喂白牦牛育肥，可以有效提高干草利用率，降低干草损耗，提高白牦牛育肥效益。

Objectives The effects of feeding white yak with micro-storage hay for fattening in high-altitude areas were studied to guide breeding farms (households) to scientifically and reasonably utilize hay to achieve the goal of cost decreasing and benefit increasing. Methods 36 healthy Tianzhu white yaks around 3 years old with a body weight of about 285 kg were randomly divided into the Group Ⅰ(control group), Group Ⅱ, and Group Ⅲ, with 12 yaks in each group. The feed was mixed according to the ratio of concentrated feed to coarse feed (4∶6). Under the same daily feeding of concentrated feed, group I was fed with dry hay, Group Ⅱwas with fed (50% dry hay+50% micro-storage dry hay), and group III was fed with micro-storage dry hay. The growth performance, slaughter performance, and economic benefits of white yaks were measured separately after 90 days of feeding and fattening inside house. Results The average daily weight gain in Group Ⅲ increased by 0.05 and 0.09 kg, compared to that in Group Ⅱ and the Group Ⅰ, respectively. The feed to weight ratio in Group Ⅰ, Group Ⅱ, and Group Ⅲ was 11.03∶1, 10.97∶1, and 10.65∶1, respectively. There were significant differences between the Group Ⅲ and Group Ⅰ in terms of growth performance.There were no significant differences among the three groups in the rate of slaughter, rate of net meat production, rate of carcass meat production and average eye muscle area. The total feed cost and the average benefits in the experimental group Ⅲ decreased by 0.33 and 0.25 yuan, and increased by 0.40 and 0.46 yuan compared to that in the experimental group Ⅱ and the experimental I with an average increase of 1 kg body weight. Conclusions Using micro-storage hay to feed white yaks for fattening in high-altitude areas can effectively improve the utilization of hay, reduce the loss of hay, and enhance the efficiency of fattening white yaks.