制霉菌素对肉鸡的生长效果及抗饲料霉变性能的研究

１６００羽红宝肉鸡分分为４组，饲喂４种含不同制霉素预混剂饲料，活性分别为（０．７０×１０８，１．４×１０８，２．１×１０８μ·ｔ－１）．进行了为期５４ｄ（１～５４ｄ日龄）的饲养试验，对各组鸡群成活率，日增重、料重比进行测定，并观察鸡群发病情况，并对制菌素饲料防霉变效果进行试验。结果表明：与对照组相比２８日龄成活率（０．７×ｌ０８μ·ｔ－１）差异显著（Ｐ＜０．０５）；高剂量组（１．４×１０８，２．１×１０８μ·ｔ－１）差异极显著（Ｐ＜０．０１）．日增重随日粮中制每菌素的增加呈提高趋势（Ｐ＞０．０５）；料重比随制霉菌素的增加呈下降趋势（Ｐ＞０．０５）．５４日龄成活率对照组与添加制霉菌素组差异极显著（Ｐ＜０．０１）；日增重对照与添加组间差异极显著（Ｐ＜０．０１）；料重比随制霉菌素增加而下降（Ｐ＜０．０５）．制霉茵素能提高日粮中Ｇｌｕ，Ｌｙｓ和Ｖａｉ三种氢基酸的代谢率，饲料中添加１．４×１０８μ·ｔ－１以上剂量制霉菌素具有良好的抑制细菌和生长作用，并且具有良好的预防雏鸡曲霉病的效果。

EFFECTS OF NYSTATIN ON GROWTH PERFORMANCE OF BROILER AND INHIBITIING MOLD GROWTH IN FEED

In experiment l,1 600 Hong Bao broilers wcre divided into four groups, and fed 0, 0.7×10 8,l.4×10 8and 2.1×10 8μ·t -1 nystatin in diets respectively from 1 to 54 days of age.Growth performance of broiler and apparent mctabolic ratc of protcin, dry matter and amino acids of diets were investigated. And than disease of chickens was observed. Experiment 2 was conducted to study the effect of nystatin on inhibiting bactcria and mold growth. The results were as follows: Addition of nystatin in broiler diets improved groweth performance of broilcrs at forcstage (1￣28 days) and whole atage (1￣54 days). Livability of birds was incrcased with nystatin increasing in dicts ( P < 0.01). Average daily gain at forestagc was increased and feed gain ratio was decrcased with nystatin increasing in dicts ( P >0.05). Compared with control, the whole stage averagc daily gain and fecd gain ratio were significantly improved with nystatin treated ( P <0.05). Nystatin increased apparent mctabolic rate of Glu. Lys and Val. When the supplementation was over l.4×10 8μ·t -1 ,nystatin had better effect on inhibiting bacteria and mold growth, and more efficiency on prcvcnting chick from mold toxicosis than the lowcr lcvel.