Abstract:To establish an effective supplementary feeding time for grazing Tibetan sheep,two groups of Tibetan sheep with similar nutritional levels and the same grazing methods were supplemented with the same amount of feed at different time periods from October 2,2022 to December 30,2022(experiment 1) and from January 1,2023 to March 31,2023(experiment 2).From the analysis of the weight gain effect,the average total weight gain during the entire period of experiment 1 was 4.50 kg,which was 0.6 kg more than the average total weight gain of 3.9 kg during experiment 2.The supplementary feeding effect was better.From the analysis of the benefits of supplementary feeding,experiment 1 increased the income by 57.15 yuan per animal,while experiment 2 increased the income by 58.65 yuan per animal.The supplementary feeding benefits of experiment 1 were slightly lower than those of experiment 2,but there was no significant difference.From the perspective of ecological benefits analysis,by combining moderate grazing on warm season grasslands with semi captive feeding and fattening in cold season,it is possible to achieve the slaughter of Tibetan sheep at the age of 12 months,which can reduce the pressure on cold season grasslands,promote changes in the production and operation mode of grassland animal husbandry,and make the Gannan pastoral area ecologically sound,productive,prosperous,and socially harmonious.Based on the comprehensive economic and ecological benefits,it can be concluded that timely supplementation of grazing Tibetan sheep is an effective way for the transformation and development of grassland animal husbandry in highaltitude pastoral areas from “relying on the nature” to “scientific animal husbandry”,and to improve the quality and efficiency of the industry.experiment 1(supplementary feeding period from October to December)is the period during which the maximum benefit of supplementary feeding and fattening is achieved for 12-month-old Tibetan sheep.