产IIa类细菌素乳酸菌对饲草青贮品质与体外瘤胃发酵特性的影响及其调控机制

In recent years, the abuse of antibiotics in animal products, antibiotic residues and drug resistance bacteria in livestock production seriously threaten food safety and people's health. Bacteriocin has been widely used in the food and feed industry because of its advantages of high efficiency, non-toxic, high temperature resistance, no residue and no resistance to drug. If add bacteriocin producing lactic acid bacteria in forage silage, it not only can improve the quality of silage, silage feed and livestock, but also can inhibit the digestive tract of harmful microbes or microbial growth, so as to reduce the use of antibiotics, silage and ensure the quality and safety of animal products and animal health. Therefore, in this study, IIa bacteriocin producing lactic acid bacteria will be used to study its impact on silage fermentation quality and aerobic stability, revealing the microbiological mechanism of bacteriocins producing lactic acid bacteria in controlling silage fermentation quality and aerobic stability; at the same time, to clarify the effect of producing a bacteriocins of lactic acid bacteria on fermentation characteristics of silage in vitro rumen and rumen microorganisms, and to provide a theoretical basis for the quality of silage fermentation and rumen fermentation of bacteriocin producing lactic acid bacteria, and to provide scientific basis for the application of bacteriocin producing lactic acid bacteria on the quality and safety of silage modulation and as a alternative to feed antibiotics.

近些年来，畜牧生产中抗生素滥用，动物性产品抗生素残留，耐药性细菌的产生，严重威胁着食品安全及人们的健康。由于细菌素具有高效，无毒、耐高温、无残留、无抗药性等优点，所以在食品和饲料行业得到了广泛应用。如果在饲草青贮时添加产细菌素乳酸菌，不仅可以提高青贮饲料的发酵品质，而且可以抑制青贮饲料及家畜消化道内有害微生物或病原微生物的生长，从而减少抗生素的使用，确保青贮饲料和畜产品质量安全以及家畜健康。为此，本研究以苜蓿青贮为研究材料，探讨产IIa类细菌素乳酸菌对青贮饲料发酵品质及有氧稳定性的影响，揭示产Ⅱa类细菌素乳酸菌调控青贮饲料发酵品质和有氧稳定性的微生物学机制；同时，澄清产Ⅱa类细菌素乳酸菌对青贮饲料体外瘤胃发酵特性及瘤胃微生物组成的影响，为产细菌素乳酸菌调控青贮饲料的发酵品质及青贮饲料瘤胃发酵提供理论基础，同时为产细菌素乳酸菌在调制优质安全青贮饲料及替代饲料抗生素中的应用提供科学依据。

在青贮时添加细菌素或产细菌素乳酸菌，不仅可以提高青贮饲料的发酵品质，而且可以抑制青贮过程中及家畜消化道内有害微生物的生长，从而减少抗生素的使用，保证青贮饲料和畜产品质量安全以及家畜健康。为此，本研究以苜蓿和全株玉米青贮为研究材料，探讨了细菌素及产细菌素乳酸菌对青贮饲料发酵品质、瘤胃体外发酵特性及甲烷产量的影响，揭示了细菌素及产细菌素乳酸菌调控青贮饲料及瘤胃体外发酵的微生物学机制。研究结果表明，接种产Ⅱa类细菌素乳酸菌菌株不仅提高了苜蓿青贮发酵品质和有氧稳定性；同时，有效降低了玉米青贮过程中干物质的损失。在苜蓿青贮中等DM含量下，ATCC14917和LP1-4分别减少了37.6%和25.5%的DM损失；而在高DM含量下，DM损失分别被降低了72.5%和35.1%。青贮时接种产生Ⅱa类细菌素菌株能够有效减少青贮发酵期间霉菌和酵母菌的数量，并能有效抑制不良微生物Aerococcus和Enterobacter的生长。产细菌素菌株作为青贮添加剂，在提高青贮发酵质量和减少CH4排放的同时，不会对接种的青贮瘤胃发酵产生不良影响。在苜蓿青贮中等DM含量下，ATCC14917和LP1-4分别减少了68.8%和43.9%的CH4产量；而在高DM含量下，CH4产量分别被降低了63.6%和78.6%。上述研究结果为产细菌素乳酸菌控制青贮饲料发酵品质、瘤胃发酵特性及甲烷排放等方面提供了理论基础，同时为产细菌素乳酸菌在生产优质安全青贮饲料及替代饲料抗生素中的应用提供了重要科学依据。