Submitted to: Canadian Journal of Animal Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 3/22/2005
Publication Date: 7/1/2005
Citation: Piva, A., Biagi, G., Luchansky, J.B., Gatta, P.P. 2005. Effect of Lactitol, Lactic Acid Bacteria, or Their Combinations (Synbiotic) on Intestinal Proteolysis in Vitro, and on Feed Efficiency in Weaned Pigs. Canadian Journal of Animal Science. 85:(3)345-353. Interpretive Summary: Over the past few decades, the use of antibiotics as growth promoters in animal feeds has accelerated the development of antibiotic-resistant bacteria in animals that may subsequently pose a risk to humans. This potential risk and the corresponding demand by consumers for a food chain free from drugs has resulted in an appreciable reduction in the use of antibiotics in animal feed. As such, alternative feed additives must be developed to control the microbial activity within the gastrointestinal tract of monogastric animals. Examples of such alternatives include the feeding of: i) live cultures (i.e., probiotics), ii) nondigestible but fermentable substrates (i.e., prebiotics) preferentially metabolized by such cultures, or iii) a preferred combination of live microbes and non-digestible oligosaccharides (NDO) (i.e., synbiotics) that beneficially improve the health of the host by achieving a favorable microbial balance in the GI tract. Our objective was to evaluate the ability of a prebiotic sugar, lactitol, to enhance the ability of probiotic bacteria, Lactobacillus brevis strain P6 4/9 and L. salivarius strain 1B 4/11, alone or in combination, to perform effectively in a model laboratory system and in weaned piglets. The results revealed that both synbiotics accounted for a significant and consistent reduction of ammonia levels, as well as an increase in production of total volatile fatty acids, in an in vitro cecal fermentation system. A synbiotic also improved the feed efficiency of piglets during a feeding trial. This study confirmed that a synbiotic can positively influence an in vitro cecal fermentation and improve feed efficiency in weaned piglets.
Technical Abstract: The objective of the present study was the investigation of different additives [lactitol, two swine isolates of lactic acid bacteria (LAB at about 10-6 CFU per ml), or the combination of lactitol (LCT) with each LAB] in an in vitro cecal fermentation, to identify the most effective strategy to ameliorate the growth performance of weaning piglets. The in vitro cecal fermentation showed that LCT alone or in combination with either LAB isolate stimulated bacterial fermentation, while the bacterial strains alone did not. Both synbiotics reduced ammonia levels after 24 h of fermentation by 29% compared to the control diet, while LCT was efective in controlling proteolysis only in the first 8 h. Compared to the control diet, all treatments increased the production of total volatile fatty acids. The most effective synbiotic in vitro was selected for use in a feeding trial with weaned piglets. Feed efficiency was improved by the synbiotic, while average daily gain and feed consumption were not affected. These data substantiated the synergistic effect of feeding a synbiotic compared with feeding a nondigestible oligosaccharide alone (i.e., LCT, a prebiotic) in modulating the cecal ecosystem and showed how synbiotics may positively influence feed efficiency when fed to pigs. Synbiotics, more than prebiotics or probiotics, may be an appropriate and effective alternative to antibiotics as growth promoters in swine.