纳豆牙孢杆菌NAT1发酵条件优化及对肉鸡免疫功能和生产性能的影响
发布时间：2019-04-02 09:46
【摘要】：肉鸡饲料中抗生素的添加,主要目的是防病促生长。而抗生素的添加引起了很多负面问题,最严重的当属耐药性的产生,耐药性导致大量细菌性疾病无法治愈,因为需要使用抗菌功能更强的抗生素,而我们对抗生素的研究速度远远跟不上细菌变异的速度,这也同时导致了人类的药物使用问题。为了探索纳豆芽孢杆菌能否替代抗生素用于肉鸡饲料中,本试验主要从三个方面进行了研究,试验一为利用工业下脚料豆粕作为培养基对纳豆芽孢杆菌进行培养,取得了1010CFU/g的芽孢产量；试验二为纳豆芽孢杆菌的饲料学研究；试验三为利用发酵的纳豆芽孢杆菌对肉鸡生产性能,免疫功能等方面的影响进行了研究。试验一,采用单因素分析法分别探究碳源、氮源、酵母粉、溶氧对纳豆芽孢杆菌生长的影响,结果发现3%葡萄糖,5%豆粕浸出液,0.75%酵母粉,300m1摇瓶培养基装量20m1时,纳豆芽孢杆菌芽孢量最多,长速较快。在这四种因素里,溶氧因素是起到主要作用的因素。然后通过正交试验,确定最优发酵培养基配方为：3%的葡萄糖,5%的豆粕浸出液,0.75%的酵母粉和300m1锥形瓶中放入20m1的发酵液时,发酵OD600达到最高12。从监测到的生长曲线可以发现,纳豆芽孢杆菌NAT1在发酵10-12小时时开始进入稳定期,0D值大约达到10.24。经过平板涂布后培养计数,得到每毫升120亿的产芽孢量。试验二,为检验纳豆芽孢杆菌是否适合饲料添加及能否通过胃肠道,进行了纳豆芽孢杆菌的细菌学性质研究。通过100℃处理10分钟,存活率100%；通过pH 2的人工胃液处理2小时,存活率为100%；通过人工胆盐处理1小时,存活率为92%。分析了纳豆芽孢杆菌发酵液中的纤维素酶,淀粉酶和蛋白酶等的酶活,纤维素酶,淀粉酶和蛋白酶,酶活分别达到了160u/ml,1500u/ml和5000u/ml。试验三,通过肉鸡饲喂含有纳豆芽孢杆菌1.8×1010/kg的饲料,对料肉比,肠道菌群和免疫功能进行了研究。定期收集粪便,血液,器官及消化道分别进行料肉比,细菌浓度,异嗜球提取及呼吸爆发功能,免疫球蛋白浓度的检测。结果显示,纳豆芽孢杆菌能够有效降低料肉比10%,提高肠道中乳酸杆菌的含量,纳豆芽孢杆菌通过肠道后芽孢量有增加,说明其在肠道内能够进行发芽并增殖。另外,在提高免疫机能方面,能够有效提高异嗜球的呼吸爆发功能,吞噬能力和免疫球蛋白IgA和IgG的浓度。本研究结果显示,利用豆粕可以规模生产纳豆芽孢杆菌,纳豆芽孢杆菌在提高肉鸡生产性能和增强机体免疫力方面可以替代抗生素,在肉鸡养殖中具有很大的潜力。
[Abstract]:The main purpose of the antibiotic in the broiler feed is to prevent and promote the growth. The addition of antibiotics has caused a lot of negative problems, the most serious when the drug resistance is generated, the drug resistance leads to a large number of bacterial diseases which can not be cured, because the antibiotics with stronger antibacterial function are needed, and the research speed of the antibiotics is far from the speed of the bacterial mutation, This also leads to the problem of human drug use. In order to explore the ability of Bacillus natto to replace antibiotics for broiler feed, the experiment was carried out in three aspects, one of which was to use the industrial waste soybean meal as the medium to culture Bacillus natto, and the spore yield of 1010 CFU/ g was obtained. In this paper, the effects of Bacillus natto on the performance and immune function of the broiler were studied. A single factor analysis was used to study the effect of carbon source, nitrogen source, yeast powder and dissolved oxygen on the growth of Bacillus natto. The results showed that Bacillus subtilis spore was the most in 3% glucose,5% soybean meal extract, 0.75% yeast powder and 300 ml shake flask culture medium. And the long-speed is faster. In these four factors, the factors of dissolved oxygen are the main factors. The optimal fermentation medium formula was determined to be 3% glucose,5% soybean meal leaching solution, 0.75% yeast powder and 300 ml Erlenmeyer flask, and the fermentation OD600 reached the highest 12. From the monitored growth curve, it was found that Bacillus natto NAT1 started to enter a stationary phase at 10-12 hours of fermentation with a value of 0 D of approximately 10.24. After the plate was coated, the count was cultured to give a spore-producing amount of 1.2 billion per milliliter. In this paper, the bacteriological properties of Bacillus natto were studied in order to test whether the Bacillus natto was suitable for the feed addition and the ability to pass the gastrointestinal tract. The survival rate was 100% by treatment with 100 鈩，
本文编号：2452464
[Abstract]:The main purpose of the antibiotic in the broiler feed is to prevent and promote the growth. The addition of antibiotics has caused a lot of negative problems, the most serious when the drug resistance is generated, the drug resistance leads to a large number of bacterial diseases which can not be cured, because the antibiotics with stronger antibacterial function are needed, and the research speed of the antibiotics is far from the speed of the bacterial mutation, This also leads to the problem of human drug use. In order to explore the ability of Bacillus natto to replace antibiotics for broiler feed, the experiment was carried out in three aspects, one of which was to use the industrial waste soybean meal as the medium to culture Bacillus natto, and the spore yield of 1010 CFU/ g was obtained. In this paper, the effects of Bacillus natto on the performance and immune function of the broiler were studied. A single factor analysis was used to study the effect of carbon source, nitrogen source, yeast powder and dissolved oxygen on the growth of Bacillus natto. The results showed that Bacillus subtilis spore was the most in 3% glucose,5% soybean meal extract, 0.75% yeast powder and 300 ml shake flask culture medium. And the long-speed is faster. In these four factors, the factors of dissolved oxygen are the main factors. The optimal fermentation medium formula was determined to be 3% glucose,5% soybean meal leaching solution, 0.75% yeast powder and 300 ml Erlenmeyer flask, and the fermentation OD600 reached the highest 12. From the monitored growth curve, it was found that Bacillus natto NAT1 started to enter a stationary phase at 10-12 hours of fermentation with a value of 0 D of approximately 10.24. After the plate was coated, the count was cultured to give a spore-producing amount of 1.2 billion per milliliter. In this paper, the bacteriological properties of Bacillus natto were studied in order to test whether the Bacillus natto was suitable for the feed addition and the ability to pass the gastrointestinal tract. The survival rate was 100% by treatment with 100 鈩，
本文编号：2452464
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