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出 处:《家畜生态学报》2011年第3期90-95,共6页Journal of Domestic Animal Ecology
摘 要:随气候变暖,仔畜成活率呈上升趋势,牲畜死损率呈下降趋势。冬季气温对牛犊成活率是主要气候影响因子,暖冬成活率高,冷冬成活率低;盛夏最低气温的变化影响牧草的生长状况,进而影响到牛群抓膘;初冬和晚冬牛群在自然游牧环境下,极端低温天气对牛群膘情的影响十分明显;秋末降水量多,冬季易形成坐冬雪使冬季放牧采食的牛群掉膘严重。初秋日照充足羊易增肥,寡照多雨羊易掉膘;初冬在自然游牧环境下,母羊产羔和羊群膘情受极端低温天气影响明显。气候生态因子通过逐步回归筛选,其影响程度通过通径系数分析用数量表达,由此建立的预测模型就更接近实际情况,对指导畜群生产及合理安排畜群结构提供科学依据。Along with climate become warm,flocks and herds pup's survive rate is rising but livestock's death rate is declining.Winter air temperature is positive impact factors for calf,warm winter calf survive rate is higher,cold winter it is lower;Midsummer lowest temperature change affect pasture's growth and cattle herd's fat;It is very distinctness which extremeness low temperature on early winter and late winter affect cattle herd's fat in naturalness feed condition;snow of the end of autumn pass by winter badly arouse cattle herd drop fat in naturalness feed condition.Sheep is fat in early autumn because sunlight is enough,Sheep is poor in early autumn because it is raininess and fewness sunlight;It is distinctness which extremeness low temperature on early winter affect ewe procreating and sheep herd's fat.it is filter meteorological factors which pass stepwize regression analysis,it is number grade which pass path coefficient analysis,the model of Predicting that build up even more near to the actual circumstance,which afford science gist in drove produce and rational plan drove structure.
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