Probiotics, prebiotics and competitive exclusion for prophylaxis against bacterial disease

Abstract

The microbial population of the intestinal tract is a complex natural resource that can be utilized in an effort to reduce the impact of pathogenic bacteria that affect animal production and efficiency, as well as the safety of food products. Strategies have been devised to reduce the populations of food-borne pathogenic bacteria in animals at the on-farm stage. Many of these techniques rely on harnessing the natural competitive nature of bacteria to eliminate pathogens that negatively impact animal production or food safety. Thus feed products that are classified as probiotics, prebiotics and competitive exclusion cultures have been utilized as pathogen reduction strategies in food animals with varying degrees of success. The efficacy of these products is often due to specific microbial ecological factors that alter the competitive pressures experienced by the microbial population of the gut. A few products have been shown to be effective under field conditions and many have shown indications of effectiveness under experimental conditions and as a result probiotic products are widely used in all animal species and nearly all production systems. This review explores the ecology behind the efficacy of these products against pathogens found in food animals, including those that enter the food chain and impact human consumers.

Influence of Probiotics on Coccidia, <i>H</i>. Contortus and Markers of Infection in Goats

“…In a Krehbiel et al (2003) review of direct-fed microbials in ruminant diets, probiotics were reported to have no beneficial influence in healthy calves. In cattle, limited probiotic influence was observed due to the ability of ruminants to degrade most probiotics (Callaway et al, 2008). More recently, Whitley et al (2009) reported that supplementing healthy, growing meat goats' diet with probiotics conferred no consistent benefits.…”

Assessment of a probiotic Containing Bacillus Subtilis on the Performance and Gut Health of Laying Japanese Quails (Coturnix Coturnix Japonica)

“…Hence, the early administration of 'good' bacteria for competitive exclusion has been proposed as a method to prevent undesirable infections. There are several reports on the capacity of live bacterial cultures (Callaway et al, 2008;Corrier et al, 1998;Nisbet et al,1998;Wagner et al, 2003) and probiotic organisms (Higgins et al, 2007;Higgins et al, 2008;Higgins et al, 2010;Patterson & Burkholder, 2003;Vicente et al, 2008) to reduce the colonization of the gastrointestinal tract of poultry by opportunistic pathogens. The current study showed that the dietary inclusion of Bacillus subtilis enhanced the birds' immunity against Newcastle disease and avian influenza.…”

Transcriptional and functional analysis of galactooligosaccharide uptake bylacSinLactobacillus acidophilus

“…Notably, the ability to selectively use a broad range of potentially prebiotic carbohydrates (6), ranging from oligosaccharides to polysaccharides, provides a competitive advantage to the beneficial microbiota during colonization of the GIT and to transient probiotic microbes (7). Prebiotic oligosaccharides are not absorbed by the host and resist degradation by intestinal acids, bile acids, and digestive enzymes, allowing them to travel through the small intestine and colon, where they may be selectively used by beneficial microbes.…”