Interpretive Summary: Supplementation of fructooligosaccharides to suckling piglets affects intestinal microbiota colonization and immune development
By: Jackie Walling
The June 2018 Issue of the Journal of Animal Science published a study investigating the effects of orally supplemented fructooligosaccharides (FOS) on intestinal development in suckling piglets. In humans, oligosaccharides are known to increase population of lactobacilli and bifidobacteria in the gut. Past studies utilizing FOS in pigs revealed positive effects on intestinal microbiota composition as well as an increased immune response to the influenza vaccine. The current study focused on gut microbiota colonization, the intestinal mucosal immune system, and the intestinal barrier function of the small intestine and colon.
Sows of third and fourth parity produced litters of 14 piglets for study. FOS administration in piglets started on day 2 of age and ended on day 14. Control and Test (FOS) piglets received a solution twice a day. Controls were given 15 mL of water and the Test received a 15 mL solution containing 5g of FOS later reduced to 6 mL (same amount of FOS) due to vomiting. Intestinal samples were collected after euthanasia on days 2, 14, and 25. Two piglets per litter were sacrificed on day 2 (1 Control/1 Test – no FOS given yet) and four piglets per litter were sacrificed on days 14 and 25 (2 Control/2 Test).
Microbiota was assessed in the jejunum and colon. Luminal microbiota in the jejunum for FOS piglets increased in diversity with high levels of Escherichia coli and a prominence of Lactobacillus and Turicibacter. Lactobacillus was dominant in Control piglets but overall diversity decreased with a significant decline in E. coli. In the colon, microbiota composition differed between FOS and Controls, but bacteria at the genus level was found to be similar. FOS supplementation also had a higher average relative contribution (ARC) over Controls concerning the groups that exert a bifidogenic effect (compound that enhances growth of Bifidobacterium): Lactobacillus, Lactobacillaceae_other, Bifidobacterium, and Bifidobacteriaceae_other.
Gene expression for metabolic, cell cycle, and immunological processes in the jejunum showed a differing trend between FOS piglets and Controls. FOS piglets had 26 depleted gene sets related to cell cycle processes and nine enriched gene sets related to extracellular matrix (ECM). Later in the study, three depleted gene sets related to chemokine/cytokine signaling were found. In the colon, gene expression showed no clear separation of treatments or significant differences in the expression of gene sets regarding the previously mentioned processes.
From the results of this study, FOS had a bifidogenic effect on the colon, but did not change gene expression. FOS only manipulated gene expression profiles concerning intestinal barrier function and immunity in the jejunum. This may be due to cross-talk between luminal microbiota and mucosal cells in the small intestine. Gene expression changes related to ECM and cell cycle processes are thought to relate to barrier function in the gut responsible for homeostasis. If negatively disrupted, the gut becomes inflamed and leads to overall health problems. The signal for this cascade of events and cross-talk is currently unknown, but this study has proven early life nutrition can alter intestinal development.
To view the full article, visit the Journal of Animal Science.