全放牧条件下不同载畜率对BMY母牛生产性能的影响

Effect of Different Stocking Rates on Production Performance in BMY Cows under 24-hour Grazing System

通过在一个产犊周期内对BMY(婆莫云杂种牛)母牛的增重和繁殖情况进行监测,探讨在全放牧条件下不同载畜率对BMY母牛生产性能的影响。结果表明:①在牧草生长期轻牧组的增重率42.2%,平均日增重0.59 kg±0.36 kg;中牧组增重率34.2%,平均日增重0.48 kg±0.30 kg;重牧组增重率27.6%,平均日增重0.35 kg±0.32 kg;试验期内相对增重及平均日增重表现为轻牧组>中牧组>重牧组,差异均不显著(P>0.05);但轻牧组由于牧草旺盛造成大量浪费。②在枯草期轻牧组的增重率0.01%,平均日增重0.03 kg±0.45 kg;中牧组的增重率-0.04%,平均日增重-0.11 kg±0.27 kg;重牧组的增重率-0.08%,平均日增重-0.21 kg±0.35 kg;试验期内增重率及平均日增重也是轻牧组>中牧组>重牧组,差异均不显著(P>0.05)。③在一个产犊周期内,繁殖成活率的排序为轻牧组83.3%>中牧组75.0%>重牧组66.6%。④综合效益分析,在3个载畜率的监测中,以中牧组的载畜率是南方类似昆明小哨的人工草场适宜的全日制轮牧模式,3个区每季度循环一次,载畜率2头/hm2,牧草生长期补矿盐,枯草期补饲青贮料、营养舔砖及混合精料,生长性能表现最佳。在云南省中海拔地区人工草地载畜率以2头/hm2为宜,外加枯草期补饲青贮和营养舔砖。

A survey on the changes of live weight gain and reproduction performances on the improved pasture during a calving period was done to investigate the effects of different stocking rates on production performances under 24-hour grazing system in BMY cows.The results showed that：① The weight gain rates and average daily gains （ADGs） of light grazing （1 cattle/hm2）,moderate grazing （2 cattle/hm2）and heavy grazing （3 cattle/hm2）groups during the grass growing season were 42.2％ and 0.59 kg ±0.36 kg,34.2％ and 0.48 kg±0.30 kg,27.6％ and 0.35 kg±0.32 kg,respectively（P＞0.05） ;② The weight gain rates and ADGs of the light grazing,moderate grazing and heavy grazing groups during the hay period were 0.01％ and 0.03 kg±0.45 kg,-0.04％ and -0.11 kg±0.27 kg,-0.08％ and-0.21 kg±0.31 kg,respectively （P＞0.05）;③ The reproductive survival rates of the light grazing,moderate grazing and heavy grazing groups were 83.3％,75.0％ and 66.6％,respectively; ④ Through comprehensive benefit analysis,it was suggested that the stocking rate of moderate grazing be available for the similar improved pastures under 24-hour grazing system patterns in South China,in which three rotational grazing plots would quarterly be recycled one time for 2 cattle/hm2.BMY cows showed the best growth when supplied lasting mineral salt during grass growing season,and silage,nutrient block and concentrate feed during dry period.Then,the suitable stocking rate for the mid-altitude improved pastures with addition of silage and nutrient block during dry period in Yunnan province would be 2 cattle/hm2.