Patterson J A, Burkholder K M
Department of Animal Sciences, Purdue University, West Lafayette, Indiana 47907, USA.
Poult Sci. 2003 Apr;82(4):627-31. doi: 10.1093/ps/82.4.627.
The intestinal microbiota, epithelium, and immune system provide resistance to enteric pathogens. Recent data suggest that resistance is not solely due to the sum of the components, but that cross-talk between these components is also involved in modulating this resistance. Inhibition of pathogens by the intestinal microbiota has been called bacterial antagonism, bacterial interference, barrier effect, colonization resistance, and competitive exclusion. Mechanisms by which the indigenous intestinal bacteria inhibit pathogens include competition for colonization sites, competition for nutrients, production of toxic compounds, or stimulation of the immune system. These mechanisms are not mutually exclusive, and inhibition may comprise one, several, or all of these mechanisms. Consumption of fermented foods has been associated with improved health, and lactic acid bacteria (lactobacilli and bifidobacteria) have been implicated as the causative agents for this improved health. Research over the last century has shown that lactic acid bacteria and certain other microorganisms can increase resistance to disease and that lactic acid bacteria can be enriched in the intestinal tract by feeding specific carbohydrates. Increased bacterial resistance to antibiotics in humans has caused an increase in public and governmental interest in eliminating sub-therapeutic use of antibiotics in livestock. An alternative approach to sub-therapeutic antibiotics in livestock is the use of probiotic microorganisms, prebiotic substrates that enrich certain bacterial populations, or synbiotic combinations of prebiotics and probiotics. Research is focused on identifying beneficial bacterial strains and substrates along with the conditions under which they are effective.
肠道微生物群、上皮细胞和免疫系统对肠道病原体具有抵抗力。最近的数据表明，这种抵抗力不仅仅取决于这些组成部分的总和，而且这些组成部分之间的相互作用也参与调节这种抵抗力。肠道微生物群对病原体的抑制作用被称为细菌拮抗、细菌干扰、屏障效应、定植抗性和竞争排斥。肠道固有细菌抑制病原体的机制包括争夺定植位点、争夺营养、产生有毒化合物或刺激免疫系统。这些机制并非相互排斥，抑制作用可能包含其中一种、几种或所有这些机制。食用发酵食品与健康改善有关，乳酸菌（乳酸杆菌和双歧杆菌）被认为是健康改善的原因。过去一个世纪的研究表明，乳酸菌和某些其他微生物可以增强对疾病的抵抗力，并且通过喂食特定的碳水化合物可以在肠道中富集乳酸菌。人类细菌对抗生素的耐药性增加，引起了公众和政府对消除家畜亚治疗剂量抗生素使用的更多关注。家畜亚治疗剂量抗生素的一种替代方法是使用益生菌微生物、富集某些细菌群体的益生元底物或益生元和益生菌的合生元组合。研究重点在于确定有益细菌菌株和底物以及它们发挥作用的条件。
