The role of the commensal gut microbial community in broiler chickens

To understand the relationship between the gastrointestinal inhabiting microbial community and broiler health, a literature review is presented. The available information on the development of gut microbial community, the relationship between commensal microflora and digestive function, the role of gut microorganisms on competitive exclusion of chickens against pathogens, and modulation of the gut microbial community by addition of prebiotics to the diet is summarized. Gut dominant microbial communities become more complex as broilers grow older. The establishment of the dominant bacterial community is affected by dietary and host-related factors. Dietary prebiotics can modulate bacterial community shift towards non-harmful bacteria, which is beneficial for the health of broiler chickens. Gut commensal microorganisms play an important role in the prevention of colonization by pathogens in the gastrointestinal tract of chickens, a process known as competitive exclusion. In conclusion, the dilemma caused by the forthcoming ban of antibiotics feed additives and need to maintain the intestinal health of broiler chickens, has produced an enormous interest in finding alternatives. Modulating the intestinal microbial community in a healthy direction, by dietary ingredients such as prebiotics, could be a good solution

Natural and synthetic oligosaccharides in broiler chicken diets

This review presents findings on the influence of natural raffinose series oligosaccharides and synthetic (industrial) products on the productivity of broiler chicken. There is evidence of negative effects on animal health and productivity from the use of raffinose series oligosaccharides, but beneficial effects from synthetic oligosaccharides. Part of this contradiction may be due to differences in the chemical nature of the supplements, the level of supple-mentation or the duration of feeding. The future for synthetic oligosaccharides is bright, but further adoption of natural sources requires a greater understanding of their chemistry to facilitate the production of beneficial compounds and the elimination of detrimental fractions. Most current literature favours the inclusion of various oligosaccharides in the diet. The cost of production could be minimised by the use of natural ingredients which contain oligosaccharides, or by cheap synthetic products, sources of which are highlighted in this review. © World's Poultry Science Association 1998