【摘要】：肉雞飼料中抗生素的添加,主要目的是防病促生長。而抗生素的添加引起了很多負(fù)面問題,最嚴(yán)重的當(dāng)屬耐藥性的產(chǎn)生,耐藥性導(dǎo)致大量細(xì)菌性疾病無法治愈,因?yàn)樾枰褂每咕δ芨鼜?qiáng)的抗生素,而我們對抗生素的研究速度遠(yuǎn)遠(yuǎn)跟不上細(xì)菌變異的速度,這也同時導(dǎo)致了人類的藥物使用問題。為了探索納豆芽孢桿菌能否替代抗生素用于肉雞飼料中,本試驗(yàn)主要從三個方面進(jìn)行了研究,試驗(yàn)一為利用工業(yè)下腳料豆粕作為培養(yǎng)基對納豆芽孢桿菌進(jìn)行培養(yǎng),取得了1010CFU/g的芽孢產(chǎn)量；試驗(yàn)二為納豆芽孢桿菌的飼料學(xué)研究；試驗(yàn)三為利用發(fā)酵的納豆芽孢桿菌對肉雞生產(chǎn)性能,免疫功能等方面的影響進(jìn)行了研究。試驗(yàn)一,采用單因素分析法分別探究碳源、氮源、酵母粉、溶氧對納豆芽孢桿菌生長的影響,結(jié)果發(fā)現(xiàn)3%葡萄糖,5%豆粕浸出液,0.75%酵母粉,300m1搖瓶培養(yǎng)基裝量20m1時,納豆芽孢桿菌芽孢量最多,長速較快。在這四種因素里,溶氧因素是起到主要作用的因素。然后通過正交試驗(yàn),確定最優(yōu)發(fā)酵培養(yǎng)基配方為：3%的葡萄糖,5%的豆粕浸出液,0.75%的酵母粉和300m1錐形瓶中放入20m1的發(fā)酵液時,發(fā)酵OD600達(dá)到最高12。從監(jiān)測到的生長曲線可以發(fā)現(xiàn),納豆芽孢桿菌NAT1在發(fā)酵10-12小時時開始進(jìn)入穩(wěn)定期,0D值大約達(dá)到10.24。經(jīng)過平板涂布后培養(yǎng)計數(shù),得到每毫升120億的產(chǎn)芽孢量。試驗(yàn)二,為檢驗(yàn)納豆芽孢桿菌是否適合飼料添加及能否通過胃腸道,進(jìn)行了納豆芽孢桿菌的細(xì)菌學(xué)性質(zhì)研究。通過100℃處理10分鐘,存活率100%；通過pH 2的人工胃液處理2小時,存活率為100%；通過人工膽鹽處理1小時,存活率為92%。分析了納豆芽孢桿菌發(fā)酵液中的纖維素酶,淀粉酶和蛋白酶等的酶活,纖維素酶,淀粉酶和蛋白酶,酶活分別達(dá)到了160u/ml,1500u/ml和5000u/ml。試驗(yàn)三,通過肉雞飼喂含有納豆芽孢桿菌1.8×1010/kg的飼料,對料肉比,腸道菌群和免疫功能進(jìn)行了研究。定期收集糞便,血液,器官及消化道分別進(jìn)行料肉比,細(xì)菌濃度,異嗜球提取及呼吸爆發(fā)功能,免疫球蛋白濃度的檢測。結(jié)果顯示,納豆芽孢桿菌能夠有效降低料肉比10%,提高腸道中乳酸桿菌的含量,納豆芽孢桿菌通過腸道后芽孢量有增加,說明其在腸道內(nèi)能夠進(jìn)行發(fā)芽并增殖。另外,在提高免疫機(jī)能方面,能夠有效提高異嗜球的呼吸爆發(fā)功能,吞噬能力和免疫球蛋白IgA和IgG的濃度。本研究結(jié)果顯示,利用豆粕可以規(guī)模生產(chǎn)納豆芽孢桿菌,納豆芽孢桿菌在提高肉雞生產(chǎn)性能和增強(qiáng)機(jī)體免疫力方面可以替代抗生素,在肉雞養(yǎng)殖中具有很大的潛力。
[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，

本文編號：2452464