Poultry gut health and beyond

Abstract

Intestinal health is critically important for the digestion and absorption of nutrients and thus is a key factor in determining performance. Intestinal health issues are very common in high performing poultry lines due to the high feed intake, which puts pressure on the physiology of the digestive system. Excess nutrients which are not digested and absorbed in the small intestine may trigger dysbiosis, i.e. a shift in the microbiota composition in the intestinal tract. Dysbiosis as well as other stressors elicit an inflammatory response and loss of integrity of the tight junctions between the epithelial cells, leading to gut leakage. In this paper, key factors determining intestinal health and the most important nutritional tools which are available to support intestinal health are reviewed.

Keywords: Feed additive; Gut leakage; Inflammation; Intestinal health; Microbiota; Poultry.

Fig. 1

The intestinal epithelial cell is the orchestrator of gut health. (A) Nutrients, prepared for absorption by the digestive enzymes, are taken up through the transcellular pathway (green arrow) by a receptor-mediated (yellow triangles) process, while the intercellular spaces are sealed by tight junctions (black arrows). (B) Gut leakage is due to opening-up of the intercellular pathway (red arrows) following tight junction loss or even complete epithelial cell loss. The ensuing uncontrolled inside-out and outside-in fluxes allow contact of potentially harmful intestinal content with the Toll-like and other receptors that trigger inflammation.