植酸酶对肉仔鸡生产性能及钙、磷利用率影响的研究

EFFECTS OF SUPPLEMENTAL MICROBIAL PHYTASEON PERFORMANCE AND UTILIZATION OFDIETARY CALCIUM,PHOSPHORUS IN BROILERS FED CORN-SOYBEAN DIETS

本试验研究肉仔鸡低磷日粮中添加植酸酶对生产性能、钙、磷利用率的影响。试验分4个处理 ,每个处理6个重复 ,每个重复15只鸡。试验分0～3、4～6、7～8周三个饲养阶段 ,分别饲喂处理1(含总磷为0.59 %、0.56 %、0.52 %) ,处理2(含总磷0.45 %、0.40 %、0.35 %加植酸酶500FTU/kg)、处理3(含总磷0.55 %、0.50 %、0.45 %加植酸酶500FTU/kg)、处理4(含总磷0.55 %、0.50 %、0.45 %加植酸酶250FTU/kg)。结果表明 :(1)各处理组平均日增重、饲料增重比差异不显著(P>0.05) ,各组腿病鸡数差异不显著(P>0.05)。处理2平均日采食量降低显著 ,为8.46 %(P≤0.05)。(2)采食每千克日粮磷的排泄量处理2、3、4比对照组分别降低24.15 %(P<0.05)、18.90 %(P>0.05)、24.93 %(P<0.05)。(3)各处理胫骨长度、灰分含量、钙含量差异不显著(P>0.05))。胫骨重量处理2显著低于对照组(P≤0.05) ,胫骨灰分中磷含量处理4显著低于对照组(P≤0.05) ,胫骨强度处理2显著低于其它处理(P≤0.05)。(4)各处理血清钙、血清磷、血清碱性磷酸酶差异不显著(P>0.05)。

A 8-weeks feeding trial with 360 day-old AA broiler chickens was conducted to study the effects of microbial phytase(Natuphos 5000) on growth performance.In trial I,the feeding trial involved 3 periods:0～3 weeks、4～6 weeks、7～8 weeks.Treatments involved a normal P level(0.59-0.56-0.52%)corn-soybean diet(Treatment 1),a low-P(0.45-0.40-0.35%)plus phytase(500 FTU/kg) diet(Treatment 2),a middle P(0.55-0.50-0.45%)level plus 500 FTU/kg phytase diet(Treatment 3),and a middle P(0.55-0.50-0.45%)level plus 250 FTU/kg phytase diet(Treatment 4).There were 6 replicates with 15 chickens in each treatment.In 56 days period,feed intake and average daily gain(ADG) were measured.In trial Ⅱ,the excretion of P were measured by total feces collection method.In trial Ⅲ,each treatment had 4 chickens(57 day old).One bird of each replicate was fasted and killed,while the others were fed for 20 minutes freely,and then were killed at 0.5h、1h、2h after feeding.Blood sample was obtained,and serum was made.And both tibia were removed.Serum Ca,P,AKP and tibia weight、length、ash content、Ca content, P content、shear stress were measured.The experimental results showsed that:(1)Treatments had no significant effect on average daily gain(ADG,P>0.05).But in comparison with the control,treatment 2 decreased the ADG by 11.95%、11.70%、11.43% in periods of 0～3 weeks、4～6 weeks、7～8 weeks and 11.80% in 8 weeks.Treatment 3 increased the ADG by 2.14%、5.90%、1.17%, and 3.14% respectively.Treatment 2 decreased feed intake by 8.46%(P≤0.05).Treatments had no effect on feed:gain ratio.(2)Treatment 2 and Treatment 4 decreased the P excretion by 24.15%、24.93%(P<0.05)respectively;treatment 3 decreased P excretion by 18.90%(P>0.05).(3)Treatments had no effect on tibia length,ash contnet,Ca content of ash(P>0.05).Treatment 2 decreased the tibia weight,shear force(P≤0.05).Treatment 4 decreased tibia P contnet(P≤0.05).Treatments had no effect on the serum P、Ca、and AKP.