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Calves health were related to the quality of entire herd,reducing the mortality rate of calves had important significance to improve the efficiency of pasture. In order to better understand the mortality rate and influencing factors on calves death,the combined methods of field survey and data analysis were adopted to analyze the mortality rate of Xinjiang Brown calves and Holstein calves. Based on the 7 157 calves records of a cattle farm in nearly 16 years, preliminary statistical analysis were taken on these data in Excel. According to the characteristics of Xinjiang climate, the seasons was divided into four parts that from March to May was spring, June to August was summer, September to November was autumn, and December to next year February was winter. Varieties of breeds were the Xinjiang Brown calves and Holstein calves, the years of birth from 1999 to 2014 was divided into 16 levels, the sex of born calves were divided into 2 levels that males and females. The effects of different years, breeds, seasons of birth, sex of calves, and different ages on the mortality rate of Xinjiang Brown calves were analyzed using SAS 8.1 software. The results showed that different breeds, years, seasons of birth, and sex of calves affected the mortality rate of Xinjiang Brown calves with different extent,the mortality rate of Xinjiang Brown calves was higher than Holstein calves (P <0.05);At one month old, the mortality rate of Xinjiang Brown calves was higher than Holstein calves (P <0.05);The mortality rate in 2006, 2009 and 2010 were higher than other years (P <0.05), the calf mortality rate was relatively small from 2011 to 2014;The mortality rate of winter seasons was higher than summer (P <0.05). To reduce the mortality rate of calves was a problem that could not be ignored in the process of cattle breeding. The calves mortality rate was affected by genetic and environmental factors, only by controlling the various environmental factors with reasonable ways, could improve the health level of calves.  相似文献   
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分析了塔吉克斯坦棉花种植区有害生物的种类、发生规律、危害以及棉花产业中有害生物综合管理(IPM)。针对该地区有害生物的特征,利用IPM的管理途径,系统地减少了有害生物对棉花生产的影响,并提出了一些适宜今后在更广泛区域推广的综合管理措施。  相似文献   
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犊牛的健康状况关系到整个牛群的质量,降低犊牛的死亡率对提高牧场的效益具有十分重要的意义。为了掌握犊牛死亡率及影响犊牛死亡的因素,试验采取实地调查与资料分析相结合的方法,对新疆褐牛犊牛及荷斯坦牛犊牛死亡率进行了分析,通过Excel对某牛场近16年的7 157条产犊记录进行初步统计,根据新疆的气候特点划分季节,3~5月为春季,6~8月为夏季,9~11月为秋季,12~次年2月为冬季;品种为新疆褐牛犊牛和荷斯坦牛犊牛,年份从1999年到2014年分为16个水平,出生犊牛性别划分为公、母2个水平。利用SAS 8.1软件分析不同年份、品种、出生季节、犊牛性别及不同月龄等因素对新疆褐牛与荷斯坦牛犊牛死亡率的影响,结果表明,品种、年份、产犊季节和犊牛性别对新疆褐牛及荷斯坦牛犊牛死亡率有不同程度的影响,新疆褐牛的犊牛死亡率显著高于荷斯坦牛(P<0.05),1月龄时,新疆褐牛的犊牛死亡率显著高于荷斯坦牛(P<0.05);2006、2009、2010年的犊牛死亡率显著高于其他年份(P<0.05),在2011~2014年,犊牛的死亡率相对较少;冬季的死亡率显著高于夏季(P<0.05)。降低犊牛的死亡率是牛群繁育过程中一个不可忽略的问题。犊牛的死亡率受到遗传和环境因素的共同影响,只有将各种环境因素给予合理控制,才能提高犊牛的健康水平。  相似文献   
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