摘要
利用240只5—8周龄的罗曼×星布罗杂交肉仔鸡,在环境温度控制室内进行了两次试验,研究六种环境温度:32、27、23、17、12和7℃对其生产性能、体成分、营养物质沉积及其利用率的影响。结果表明:1.温度对日增重有明显的影响,日增重效果以27℃和23℃最高,分别为37.31克和38.80克;7℃最低,仅24.61克。并且在日增重(Y)与温度(X)之间有一定的二次抛物线关系,其中在公鸡为:Y=4.7450+2.9348X-0.0617X^2(P<0.10);在母鸡为:Y=8.9259+2.1105X-0.0457X^2(P<0.10)。2.高温和低温对饲料利用率均有明显的影响,27℃和23℃单位增重的耗料量最少,7℃最多;并且在饲料效率(y)和温度(x)之间有极显著的倒二次抛物线关系,其中在公鸡为:y=3.8541-0.1 12 5x+0.002 4x^2(P<0.01)母鸡为:y=4.06-0.1153x+0.0024x^2(P<0.01)。因此,根据试验结果综合,可以认为温度在23-24.5℃时,鸡的日增重和饲料效率较好。3.随环境温度的升高,胴体的发热量和脂肪含量增加,蛋白质和水分含量减少,4.能量、脂肪和蛋白质的沉积量在23—27℃时最多,7℃时最少。5.随温度的升高,肉仔鸡对饲粮 ME 和 CP 的利用率提高,27℃时达最高值,高于27℃,两者的利用率均下降。
The experiment was conducted to study the effects of environmental temperature on the perfomance,body oomposition,nutrient gain and nutrient efficiency of the 5—8week old broilers.The temperatures used in the experiment were 32,27, 23,17,12 and 7℃.The broilers used in the experiment were Lohmann×Starbro cross—bred.The following results were noted: 1.There was a significant effect of temperature(X)on daily gain(Y). The optimum temperature of the 5—8week old broiler was 23—27℃.It conformed to a second degree polynomial equation;Y=4.7450+2.9343X-0.0617X^2 for males and Y=8.9259+2.1105X-0.0757X^2 for females. 2.Both high temperature and low temperature(X)had significant effcets on feed efficiency(Y).The best efficiency could be obtained between 23℃ and 27℃. For males,Y=3.8501-0.1125X+0.0024X^2 for females,Y=4.0600—0.1153X+0.0024X^2. 3.Carcass combustible and fat content increased as temperature was increased, but protein and moisture content decreased. 4.Energy,protein and fat gain increased with temperature from 7℃ to 23℃, reaching a peak between 23℃ and 27℃,followed by a decrease as the tempera- ture was raised further. 5.The efficiency of dietary ME and CP increased as temperature was increased, reaching a peak between 23℃ and 27℃,followed by a decrease as the temperatu- re was raised further.
