The live cattle eye muscle area, back-fat thickness, height of eye muscle and intramuscular fat content were determined by ultrasonic technology. The prediction model for meat production performance was established. T...The live cattle eye muscle area, back-fat thickness, height of eye muscle and intramuscular fat content were determined by ultrasonic technology. The prediction model for meat production performance was established. The numerical value had high reliability and accuracy, which reached extremely significant difference via analysis of variance. The study provides scientific basis for breeding and meat evaluation of beef cattle.展开更多
为了筛选适用于规模化牛场的最佳肉牛定时输精方案,探究定时输精技术对经产母牛繁殖性能的影响,试验将膘情良好且子宫、卵巢发育良好的产后未观察到自然发情的不同胎次西门塔尔母牛111头随机分为试验1,2,3,4组,每组分别为30,28,28,25头...为了筛选适用于规模化牛场的最佳肉牛定时输精方案,探究定时输精技术对经产母牛繁殖性能的影响,试验将膘情良好且子宫、卵巢发育良好的产后未观察到自然发情的不同胎次西门塔尔母牛111头随机分为试验1,2,3,4组,每组分别为30,28,28,25头,分别采用4种不同定时输精方案(双同期-11、G-6-G、G P E和G P A法)进行处理,测定同期发情率、情期受胎率、产后空怀天数、体况评分(BCS)等指标,用于评价不同方案的输精效果,同时分析了不同胎次和体况评分对输精效果的影响。结果表明:试验1组(双同期-11法)情期受胎率最高,为68.97%,显著高于其他组的41.67%~48.15%(P<0.05);体况评分5分组的情期受胎率最低,为16.67%,与体况评分7分组差异显著(P<0.05),与体况评分6分组差异极显著(P<0.01);3胎次及以上组情期受胎率最低,为35.29%,与1,2胎次组差异显著(P<0.05),且2胎次发情头数最多。说明试验1组(双同期-11法)定时输精方案效果最好,体况评分为6〜7分的母牛情期受胎率较高,且胎次对定时输精效果影响较为明显。展开更多
Breeding high-yielding and nutrient-efficient cultivars is one strategy to simultaneously resolve the problems of food security,resource shortage,and environmental pollution.However,the potential increased yield and r...Breeding high-yielding and nutrient-efficient cultivars is one strategy to simultaneously resolve the problems of food security,resource shortage,and environmental pollution.However,the potential increased yield and reduction in fertilizer input achievable by using high-yielding and nutrient-efficient cultivars is unclear.In the present study,we evaluated the yield and nitrogen use efficiency(NUE) of 40 commercial maize hybrids at five locations in North and Northeast China in 2008 and 2009.The effect of interaction between genotype and nitrogen(N) input on maize yield was significant when the yield reduction under low-N treatment was 25%-60%.Based on the average yields achieved with high or low N application,the tested cultivars were classified into four types based on their NUE:efficient-efficient(EE) were efficient under both low and high N inputs,high-N efficient(HNE) under only high N input,low-N efficient(LNE) under only low N input,and nonefficient-nonefficient under neither low nor high N inputs.Under high N application,EE and HNE cultivars could potentially increase maize yield by 8%-10% and reduce N input by 16%-21%.Under low N application,LNE cultivars could potentially increase maize yield by 12%.We concluded that breeding for N-efficient cultivars is a feasible strategy to increase maize yield and/or reduce N input.展开更多
基金Supported by Major Science and Technology Project of Xinjiang Uygur Autonomous Region(201230116-10)
文摘The live cattle eye muscle area, back-fat thickness, height of eye muscle and intramuscular fat content were determined by ultrasonic technology. The prediction model for meat production performance was established. The numerical value had high reliability and accuracy, which reached extremely significant difference via analysis of variance. The study provides scientific basis for breeding and meat evaluation of beef cattle.
文摘为了筛选适用于规模化牛场的最佳肉牛定时输精方案,探究定时输精技术对经产母牛繁殖性能的影响,试验将膘情良好且子宫、卵巢发育良好的产后未观察到自然发情的不同胎次西门塔尔母牛111头随机分为试验1,2,3,4组,每组分别为30,28,28,25头,分别采用4种不同定时输精方案(双同期-11、G-6-G、G P E和G P A法)进行处理,测定同期发情率、情期受胎率、产后空怀天数、体况评分(BCS)等指标,用于评价不同方案的输精效果,同时分析了不同胎次和体况评分对输精效果的影响。结果表明:试验1组(双同期-11法)情期受胎率最高,为68.97%,显著高于其他组的41.67%~48.15%(P<0.05);体况评分5分组的情期受胎率最低,为16.67%,与体况评分7分组差异显著(P<0.05),与体况评分6分组差异极显著(P<0.01);3胎次及以上组情期受胎率最低,为35.29%,与1,2胎次组差异显著(P<0.05),且2胎次发情头数最多。说明试验1组(双同期-11法)定时输精方案效果最好,体况评分为6〜7分的母牛情期受胎率较高,且胎次对定时输精效果影响较为明显。
基金supported by the National Basic Research Program of China (2011CB100305,2009CB11860)the National Natural Science Foundation of China (31121062,31172015)the Special Fund for Agriculture Profession (201103003)
文摘Breeding high-yielding and nutrient-efficient cultivars is one strategy to simultaneously resolve the problems of food security,resource shortage,and environmental pollution.However,the potential increased yield and reduction in fertilizer input achievable by using high-yielding and nutrient-efficient cultivars is unclear.In the present study,we evaluated the yield and nitrogen use efficiency(NUE) of 40 commercial maize hybrids at five locations in North and Northeast China in 2008 and 2009.The effect of interaction between genotype and nitrogen(N) input on maize yield was significant when the yield reduction under low-N treatment was 25%-60%.Based on the average yields achieved with high or low N application,the tested cultivars were classified into four types based on their NUE:efficient-efficient(EE) were efficient under both low and high N inputs,high-N efficient(HNE) under only high N input,low-N efficient(LNE) under only low N input,and nonefficient-nonefficient under neither low nor high N inputs.Under high N application,EE and HNE cultivars could potentially increase maize yield by 8%-10% and reduce N input by 16%-21%.Under low N application,LNE cultivars could potentially increase maize yield by 12%.We concluded that breeding for N-efficient cultivars is a feasible strategy to increase maize yield and/or reduce N input.
