Study On Animal Production System Of Summer-autumn Grazing And Winter-spring Shed Feeding In Cropping-pastoral Interlacing Regions

This study was conducted on the typical grassland of Helinger,through the study of summer-autumn grazing and winter-spring shed feeding,the characteristics of grassland community under different grazing patterns were compared.The experimental results are as follows:(1)Through a three-year field survey,it was found that there were 20 families and 52 genera in the study area.Gramineae,Asteraceae,and Leguminosae account for a large proportion.Xerophila perennials account for more than half,and perennial Gramineae are the dominant species.From the ecological and life forms of plants,the type of grassland is typical grassland.(2)Through the determination of grassland conditions,it was found that the seasonal changes in vegetation productivity were obvious,and greening was completed in late May.Grazing at this time had little effect on grassland vegetation and can achieve sustainable use of grassland.(3)Evaluation of indicators such as community size characteristics,grassland productivity and diversity indices showed that rotational grazing methods such as rotational grazing,free grazing,and continuous grazing were the best among rotational grazing areas compared with non-grazing areas..(4)A two-year grazing experiment showed that after 6 months of grazing,the sheep can only reach a weight of 45 kg or more.Comparing the weights of sheep under different grazing methods,the sheep in the zoning and grazing areas had the highest weight gain,and the weight gain of the grazing animals was 13.29 kg/ha for 6 months.The free grazing area was similar to that of 12.87 kg/sheep.In the continuous grazing area,the weight gain of the sheep was the smallest,only 6.94kg/sheep.However,there was a problem of high investment in infrastructure construction cost and impact on short-term economic benefits.(5)The results of 4 feeding trials using local forage materials for feeding and formulating showed that there was no significant difference in the average weight gain of the sheep,and no dropping was observed.Sheep that had been formulated with 60% Caragana korshinskii + 20% corn stover + 20% premixed concentrate only gained 2 kg during the 4-month winter feeding period.When the daily feed amount is 2 kg/sheep,the feed cost for the four formulas was 242.4-290.4 yuan/sheep.For the predominant use of local crop products(70% corn stover + 20% corn seed),the formula with a small amount of premixed concentrate(10%)was the most economical.