论文标题:“富硒益生菌”在蛋鸡生产中的应用研究
Study on the Application of Selenium-Enriched Probiotics in Hen Production
论文作者
论文导师 黄克和,论文学位 硕士,论文专业 临床兽医学
论文单位 南京农业大学,点击次数 93,论文页数 72页File Size4179K
2007-05-01论文网 http://www.lw23.com/lunwen_3564562/
selenium-enriched probiotics;; hen;; productive performance;; egg selenium;; antioxidation function;; digestive enzyme;; intestinal microflora;; cholesterol
硒是人和动物所必需的微量元素，具有提高机体免疫力、抗癌、抗自由基、延缓衰老、拮抗有毒元素、防治某些地方性流行病等多种功能。日粮补硒已是许多国家养殖业采取的常规措施，当前广泛使用的补硒方法是在日粮中添加亚硒酸钠，但由于其利用率低、毒性大、而且会对环境造成潜在的污染，因此在有些国家已被限量使用。富硒益生菌是利用生物转化的原理，应用益生菌将无机硒转化为有机硒的有机硒制剂，可发挥有机硒和益生菌的双重作用。本论文主要研究了富硒益生菌对蛋鸡生产性能、抗氧化能力、肠道菌群与消化酶活性及鸡蛋中硒、胆固醇含量的影响，为富硒益生菌在蛋鸡生产中的应用提供理论依据。具体研究内容如下： 1．研究了富硒益生菌对蛋鸡生产性能、蛋品质及蛋硒含量的影响。将700羽58周龄罗曼蛋鸡随机分为7组，每组5个重复，对照组饲喂基础日粮，其它各组在基础日粮中以两个水平分别添加富硒益生菌、亚硒酸钠和益生菌，进行为期35 d的饲养试验。试验过程中记录蛋鸡的生产性能，每7 d从各组每个重复中随机任取2枚蛋测定蛋硒含量，并于试验第32 d从各重复中任取12枚蛋，其中6枚当天进行常规蛋品指标测定，另外6枚室温贮存5 d后测定哈夫单位。结果表明，日粮中添加富硒益生菌可显著提高蛋鸡产蛋率(P<0.01)、日产蛋量(P<0.01)、平均蛋重(P<0.01)，降低料蛋比(P<0.05)；显著提高室温下贮藏5 d的蛋样的哈夫单位(P<0.01)，但在蛋形指数、蛋壳强度、蛋壳厚度、蛋黄颜色、蛋黄率及新鲜蛋的哈夫单位等蛋品质指标上与对照组差异不显著(P>0.05)；随着日粮中硒添加量的增加，硒在蛋中的沉积显著(P<0.01)增加，相同水平的硒添加量富硒益生菌较亚硒酸钠更能显著(P<0.01)提高蛋硒含量。 2．研究了富硒益生菌对蛋鸡抗氧化能力和肠道菌群及消化酶活性的影响。选用140羽65周龄罗曼蛋鸡随机分为7组，每组5个重复。试验处理与饲养管理同上。于试验第15d和35 d测定血液中谷胱甘肽过氧化物酶(GSH-Px)、超氧化物歧化酶(SOD)活性和总抗氧化能力(T-AOC)；试验结束时，从各组每个重复中任选2只鸡扑杀，对盲肠微生物进行计数并测定十二指肠消化酶活性。结果表明，富硒益生菌和亚硒酸钠均能显著(P<0.01)提高蛋鸡全血GSH-Px活性、血浆SOD活性和血浆T-AOC，且富硒益生菌提高全血GSH-Px活性和血浆T-AOC的效果优于亚硒酸钠(P<0.05)；日粮中添加富硒益生菌和益生菌蛋鸡盲肠内容物中乳杆菌(P<0.01)和双歧杆菌(P<0.05)的数量显著增加，而肠杆菌(P<0.01)、葡萄球菌(P<0.01)和肠球菌(P<0.05)的数量显著减少；富硒益生菌和益生菌能显著提高蛋鸡十二指肠内容物淀粉酶(P<0.01)及脂肪酶(P<0.05)的活性，对胰蛋白酶和总蛋白酶活性没有显著影响。 3．研究了富硒益生菌对蛋鸡脂代谢的影响。试验设计同上，试验结束时，从各组每个重复中任取2枚蛋，测定蛋黄中胆固醇的浓度；每个重复任选2只鸡，翅下静脉采血，测定血清中总胆固醇(TC)、高密度脂蛋白(HDLC)、低密度脂蛋白(LDL-C)和甘油三酯(TG)的含量。结果表明，日粮中添加富硒益生菌可显著降低血清TC、LDL-C及蛋黄胆固醇的浓度(P<0.01)，但不同添加水平之间差异不显著((P>0.05)；富硒益生菌对血清TG、HDL-C无显著影响(P>0.05)。
Selenium is an essential trace element for animals and human. Its functions include improving immunity, preventing cancer, resisting free radicals, postponing aging, detoxification from some heavy metals, and preventing some local epidemic etc. In many countries, supplementation of selenium in animal diet is a routine step on animal husbandry. Adding sodium selenite as inorganic selenium in animal diet has been set limit in some countries because inorganic selenium has disadvantages of lower biological utilization ratio, higher toxicity and potential environmental pollution. Selenium-enriched probiotics(Se probiotics) is an organic selenium-enriched product which translated inorganic selenium into organic selenium by probiotics fermentation, act as not only organic selenium but also probiotics. The purpose of the present paper was to study the effect of Se probiotics on the production performance, antioxidative function, intestinal microflora, digestive enzyme activities and egg selenium and cholesterol concentrations of hen, and make a guide for the application of Se probiotics in hen production. The research contents were as follows: 1. Effects of Se probiotics on the production performance, egg quality and egg selenium concentrations in hens were studied. Seven hundred 58-week old Rohman laying hens were randomly allocated into seven groups, with 5 replicates of 20 hens in each. Se probiotics, sodium selenite and probiotics were added into basal diet at 2 levels respectively. The basal diet was served as control. The experiment lasted for 35 days. During the experiment, production performance was recorded, two eggs per replicate from each group were randomly collected every 7 days for egg Se concentrations analyses, and another 12 eggs per replicate were collected on days 32 to evaluate egg quality parameters. The results showed that, supplementation of Se probiotics significantly increased laying rate(P<0.01), hen day egg production(P<0.01) and mean egg weight(P<0.01), decreased feed/egg ratio(P<0.05). Egg quality of fresh eggs was not affected by the supplementation(P>0.05), but haugh unit measured on eggs stored at room temperature for 5 days was significantly improved(P<0.01). Egg Se concentrations were linearly increased(P<0.01) for the supplementation of Se from either Se source, but at the same supplemental Se levels, eggs from hens fed Se probiotics had higher(P<0.01) Se concentrations than those fed sodium selenite. 2. Effects of Se probiotics on antioxidative activities, intestinal microflora and digestive enzyme activities in laying hens were studied. One hundred and forty 65-week old Rohman laying hens were randomly divided into seven groups, with 5 replicates of 4 hens in each.Experiment treatment as before. During the experiment, blood was sampled on days 15 and 35 for whole-blood GSH-Px activity, plasma SOD and T-AOC activity assay. At the end of the experiment, two hens per replicate from each treatment were slaughtered for the quantitation of cecal microflora and estimation of digestive enzyme in intestinal contents. The results showed that the addition of Se probiotics or sodium selenite to the diet significantly increased(P<0.01) the whole-blood GSH-Px activity, plasma SOD activity and T-AOC in comparison to the control. There was a more significant increase(P<0.05) in whole-blood GSH-Px activity and T-AOC from hens fed Se probiotics than those fed sodium selenite. Supplementation with Se probiotics or probiotics significantly increased the amouns of cecal Lactobacillus(P<0.01) and Bifidobacterium(P<0.05), decreased the amouns of cecal Escherichia coli(P<0.01), Staphylococcus(P<0.01) and Enterococcus(P<0.05). Either Se pobiotics or probitics increased significantly the levels of amylase(P<0.01) and lipase(P<0.05) activties in duodenum contents. However, the trypsin and protease activities were not affected by addition of either Se-pobiotics or probitics. 3. Effect of Se probiotics on lipid metabolism in hens were studied. Experiment animals and treatment as before. At the end of the experiment, two eggs per replicate from each treatment were collected for measuring yolk cholesterol, and blood was sampled from each of 2 hens in each replicate, the sera were separated for estimation of serum total cholesterol(TC), high density lipoprotein cholesterol(HDL-C), low density lipoprotein cholesterol(LDL-C) and total triglycerides(TG). The results showed that, the addition of Se probiotics significantly ruduced(P<0.01) the contaitions of serum TC, LDL-C and yolk cholesterol. However, no difference in these traits was observed between the groups receiving different levels of Se probiotics. Serum TG and HDL-C were less affected by Se probiotics.
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