【作者】 孙冰锋；

【导师】 龚月生；

【作者基本信息】 西北农林科技大学 ， 动物营养与饲料科学， 2005， 硕士

【摘要】 为了适应人们对绿色食品的需要,减少抗生素在肉鸡饲料中的应用,本文研究了不同类型复合酸化剂对肉仔鸡的影响,并将其与益生素进行组合,研究其对肉仔鸡的组合作用效果,以期达到减少甚至替代抗生素在肉鸡饲料中应用的目的。试验一:不同类型复合酸化剂对肉仔鸡生产性能的影响。试验选用1 日龄健康艾维因商品代肉仔鸡200 只,随机分成4 组,其中试验组3 组,对照组1 组,每组设5 个重复,每个重复10 只鸡(公、母各半)。试验组日粮按0.15%的量添加复合酸化剂,其中试验组1 添加的为磷酸型复合酸化剂,试验组2 添加的为柠檬酸型复合酸化剂,试验组3 添加的为乳酸型复合酸化剂,对照组使用基础日粮(不含抗生素)。试验结果表明:不同类型复合酸化剂均不同程度的提高了肉仔鸡的生产性能,其中试验2 组最好,前期(0~3 周龄)日只增重比对照组提高了5.80%,且差异显著(P<0.05),后期(4~5 周龄)日只增重比对照组提高了4.9%,但差异不显著(P>0.05),全期料肉比比对照组下降了1.6%,且差异显著(P<0.05),比对照组多耗料3.5%,死亡率下降了66.67%,差异均不显著(P>0.05)。试验二:酸化剂、益生素及其组合添加对肉仔鸡生产性能、肠道pH 值以及肠道微生物数量的影响。试验选用1 日龄健康艾维因商品代肉仔鸡765 只,随机分成17 组,每组设3 个重复,每个重复15 只鸡。酸化剂添加水平为0.1%,0.2%,0.3%,益生素添加水平为0.2%,0.4%,0.6%,并将其进行两两组合,共计9 个组合,再加上一个空白对照组和一个抗生素对照组(金霉素,50mg/kg),共计17 组。试验结果表明: 在肉仔鸡日粮中添加不同水平的酸化剂,均不同程度的提高了肉仔鸡的生产性能,其中以0.2%的添加水平效果最好。与对照组相比,提高日只增重12.5%且差异显著(P<0.05),提高日只耗料量3.68%,但差异不显著(P>0.05),降低料肉比13.21%且差异显著(P<0.05),降低死亡率33.31%,但差异不显著(P>0.05),效果不如抗生素对照组(P<0.05)。在肉仔鸡日粮中添加不同水平的益生素,均不同程度的提高了肉仔鸡的生产性能,其中以添加0.4%的益生素效果最好。与对照组相比,提高日只增重18.07%,且差异显著(P<0.05),提高了日只耗料量0.98%,差异不显著(P>0.05),效果不如抗生素对照组(P<0.05),降低料肉比14.47%,差异显著(P<0.05),降低死亡率49.96%,差异不显著(P>0.05)。不同水平酸化剂和益生素组合添加的效果优于单一添加益生素或者酸化剂,其中酸化剂0.1%和益生素0.4%组合效果最好。提高日只增重28.30%,提高日只耗料量8.12%,降低料肉比15.72%,降低死亡率66.69%,与空白对照组相比,更多还原

【Abstract】 In order to meet the needs of people for green food, decreasing the uses of antibiotics in broiler’s feeds, we studied the effects of different style acidifer in broilers, at the same time, combined it with probiotics to study their combinative effects, hopining to decrease or replace the uses of antibiotics in broiler’s feed. Experiment 1: The experiment were conducted to study the effects of adding 0.15% different kinds of acidifier on the performance of broilers. 200 one-day old commercial broilers were allocated randomly to four treatments of five replicates, ten birds each (male: female, 1:1), the control group using basic diet (no antibiotics). The results shows that adding acidifier can improve the average daily gain,decrease the feed gain ratio and dying ratio of broilers. Effects of former stage are better than that of the latter stage. Among them, the best is treatment 2, the second is treatment 1, and the last is treatment3. Compare with the control group , treatment 2significantly increased the 0~3 week broiler’s average daily gain of 5.80%(P<0.05),increased4~5 week broiler’s average daily gain of 4.9%(P>0.05),decreased feed gain ratio of 1.6%(P<0.05), dying ratio of 66.67%, increased feed intake of 3.5%,but both insignificant(P>0.05). Experiment 2: The experiment were conducted to study the effects of acidifer, probiotics and their combintion on the broilers performance, intestinal pH and intestinal microflora population of broilers.765 one-day old commercial broilers were allocated randomly to 17 treatments of three replicates,15 birds each,among them ,treatment 1 use basic diets , treatment 17 use antibiotics(aureomysin, 50mg/kg) The addition levels of acidifer are 0.1%,0.2%,0.3%,the addition level of probiotics are 0.2%,0.4%,0.6%. The results show that: Adding different level of acidifer can improve the performance of broilers, the fitting adding level is 0.2%,it significantly increased the broiler’s average daily gain of 12.5%(P<0.05), increased feed intake of 3.68% , but insignificant(P<0.05),significantly decreased the feed gain ratio of 13.21%(P<0.05),decreased dying ratio of 33.31%,but insignificant (P>0.05),its effects is worse than the antibiotics treatment(P<0.05). Adding different level of probiotics can improve the performance of broilers, the fitting adding level is 0.4%.Compare with the control group, it significantly increased the broiler’s average daily gain of 18.07% ( P<0.05 ) , increased feed intake of 0.98% , but insignificant(P<0.05),significantly decreased the feed gain ratio of 14.47%(P<0.05),decreased dying ratio of 49.96%,but insignificant (P>0.05). Effects of combinative addition of acidifer and probiotics are better than only adding one of them. The best combination is adding 0.1% acidifer and 0.4% probiotics. Compare with the control group, significantly increased the broiler’s average daily gain of 28.30%, feed intake of 8.12% ,decreased the feed gain ratio of 15.72%,dying ratio of66.69%(P<0.05), its effects is as good as adding antibiotics. Adding 0.2% acidifer or combinative adding0.1% acidifer and 0.4% probiotics in broiler’s daily diet can both significantly decrese the broiler’s intestinal pH(P<0.01). Adding 0.2%acidifer or 0.4% probiotics or combinative adding0.1% acidifer and 0.4% probiotics in broiler’s daily diet can all decrease the E.Coli concentrion of jejunum and cecum, increasing the Lactobacillus concentrion of jejunum and cecum, but effects of combinative adding 0.1%acidifer and 0.4% probiotics is the best. significantly decreased the E.Coli concentrion of jejunum and cecum(P<0.01),as good as the antibiotics treatment ,significantly increased the Lactobacillus concentrion of jejunum and cecum, its effects is better than then adding antibiotics. Experiment 3: At the 21 day, after weighed the brioers, selected 6 bird (2 each replicates one is male, the other is femal) from the best treatment of only adding acidifer (2,3,4), only adding probiotics (5,9,13) and combinativeadditon of acidifer and probiotics (6,7,8,10,11,12,14,15,16) and zero control group, antibiotics group to study their effects for CPU and MEU. The result shows that adding 0.2% acidifer or adding 0.4% probiotics or combinatively adding o.2% acidifer and 0.4% in broiler feed can all improve the utilization of CP and ME of broiler’s daily diets. The effects of Adding 0.4% probiotics is better than that of adding 0.2% acidifer, among them ,the combinative addition is the best , it significantly increased the utilization of CP(P<0.01), decreased the utilization of ME of broiler’s daily diets(P<0.05), Its effects is as good as adding antibiotics(P>0.05).更多还原