氯化铵对肉仔鸡热应激的影响

Effect of ammonium chloride on heat stress of broilers

通过离子平衡途径,在肉仔鸡日粮中添加氯化铵,观察其对家禽热应激的影响。将270只1日龄艾维茵肉雏鸡随机分为5个处理,每处理设3个重复,试验持续到5周龄。试验模拟夏季高温环境,全期人工控温28～35℃。1～28日龄进行饲养试验;29～34日龄进行代谢试验。5组试验日粮为:Ⅰ为正对照组,21%CP;Ⅱ为Ⅰ组日粮+0 62%氯化铵;Ⅲ为负对照组,19%CP;Ⅳ为Ⅲ组日粮+0 62%氯化铵;Ⅴ为Ⅲ组日粮+1 00%氯化铵。试验结果表明:Ⅱ、Ⅲ、Ⅳ和Ⅴ组肉仔鸡期末体重、日增重、采食量和饲料转化率与对照组无显著差异,Ⅴ组21日龄体重显著降低(P<0 05);Ⅱ和Ⅴ组显著提高CP、Ca和P的表观代谢率(P<0 05),Ⅴ组P除外;Ⅴ组粪便含水率明显增加(P<0 01);Ⅲ、Ⅳ组与对照组代谢指标差异不显著。

Heat stress in summer usually causes descending performance and increasing mortality of broiler chicks. An experiment was conducted through adding ammonium chloride (AC) to broilers diets to examine the effect of the additive on their heat stress. 270 broiler chicks one day posthatching were randomly assigned to five groups with three replicates per treatment: (1) Positive control, 21%CP; (2) Positive control ration+0.62% ammonium chloride; (3) Negative control, 19%CP; (4) Negative control ration+0.62%AC; (5) Negative control ration+1.00%AC. The temperature was controlled in 28～35℃ through five weeks in which feeding experiment was conducted from 1 to 28 day and metabolizing experiment from 29 to 34 day. Treatment two、three、four and five were similar to positive control in live weight (LW)、average daily gain (ADG)、feed consumption (FC) and feed efficiency (FE). However, treatment five lowered significantly in LW than other treatments on 21 day (P<0.05). There were significant improvements in apparent metabolizing of CP、Ca and P in treatment two and five comparing with the control (P<0.05) except of P in treatment five. Treatment five increased water content of manure (P<0.01). No significant differences were observed in treatment three and four comparing with the control in metabolizing parameters..