Gut health: The results of microbial and mucosal immune interactions in pigs

Abstract

There are a large number of microorganisms in the porcine intestinal tract. These microorganisms and their metabolites contribute to intestinal mucosal immunity, which is of great importance to the health of the host. The host immune system can regulate the distribution and composition of intestinal microorganisms and regulate the homeostasis of intestinal flora by secreting a variety of immune effector factors, such as mucin, secretory immunoglobulin A (sIgA), regenerating islet-derived III (RegIII)γ, and defensin. Conversely, intestinal microorganisms can also promote the differentiation of immune cells including regulatory T cells (T reg ) and Th17 cells through their specific components or metabolites. Studies have shown that imbalances in the intestinal flora can lead to bacterial translocation and compromised intestinal barrier function, affecting the health of the body. This review focuses on the composition of the pig intestinal flora and the characteristics of intestinal mucosal immunity, discusses the interaction mechanism between the flora and intestinal mucosal immunity, as well as the regulation through fecal microbiota transplantation (FMT), dietary nutritional composition, probiotics and prebiotics of pig intestinal microecology. Finally, this review provides insights into the relationship between intestinal microorganisms and the mucosal immune system.

Bacterial and Viral Co-Infection in the Intestine: Competition Scenario and Their Effect on Host Immunity

“…Innate immunity cells comprise a diverse group of cell types, including intestinal epithelial cells (IECs) [19], mononuclear macrophages, dendritic cells, natural killer cells, mast cells, granulocytes, M cells, etc. The immune effectors are mainly substances secreted by immune cells, such as mucin, secretory immunoglobulin A (sIgA), and defensins [20]. IECs, mononuclear phagocytes, and gut-associated lymphoid tissue play an important role in sensing elements of the gut microbiome and in regulating the immune response [21].…”

Domestication Explains Two-Thirds of Differential-Gene-Expression Variance between Domestic and Wild Animals; The Remaining One-Third Reflects Intraspecific and Interspecific Variation

“…The practical value of Belyaev’s concept has been realized in a huge collection of commercial fur colors—e.g., “Amber-gold pastel,” “Ashen,” “Beige,” “Black crystal,” “Cobalt,” “Ermine-like,” “Peach,” ““Pearl,” Platinum,” “Purple,” “Silver sable-like,” “Steel-blue,” and “Straw,”—rarely or never seen in the wild [ 6 ]. The concept’s fundamental importance has found confirmation in a large variety of breeds of dogs [ 7 ], cats [ 8 ], pigs [ 9 ], cows [ 10 ], horses [ 11 ], sheep [ 12 ], goats [ 13 ], chickens [ 14 ], ducks [ 15 ], geese [ 16 ], and other domestic animals [ 17 ] as well as in artificial shelters and additional feeding for wild animals in wildlife for saving them [ 18 ]. On the basis of Belyaev’s concept [ 1 ], a laboratory model of animal domestication by humans has been created using outbred lines of tame and aggressive rats artificially bred [ 19 ] for performance on a standard glove test [ 20 ].…”

Hydrolyzed Yeast Supplementation to Newly Weaned Piglets: Growth Performance, Gut Health, and Microbial Fermentation

“…A higher IgA concentration is likely attributed to the activation of humoral immunity on the mucosal surface. It plays an essential role in preventing the epithelial mucosa from pathogen invasion and maintaining mucosal homeostasis [24]. Based on the unique structure of the yeast-derived β-glucan of Saccharomyces cerevisiae, which has a thick cell wall (~115 nm) and small particles, it induces its interaction between the host immune system [18].…”