Effects of fasting on intestinal barrier and sensory vagus receptor expression in yellow-feathered broilers

Objective  The aim of this study was to investigate the changes of intestinal inflammatory signals and vagal nerve related receptors in yellow-feathered broilers under starvation.

Method Yellow-feathered broilers were used in the experiment. They were randomly divided into control group and fasting group according to the principle of consistent body weight. The expressions of appetite peptides, intestinal tight junction proteins and inflammatory factors in hypothalamus and receptors related to inflammation and appetite regulation in nodose ganglia (NG) of yellow-feathered broilers were detected by q-PCR. The morphological changes of intestinal tract were observed and statistically analyzed by electron microscopy and HE staining.

Result Compared with the control group, short-term fasting increased the expressions of hypothalamic orexigenic peptides AgRP (P<0.05) and NPY (P<0.01). Short-term fasting increased the concentration of intestinal H₂O₂, promoted the expressions of small intestinal tight junction protein (P<0.05), decreased the proportion of jejunal injury (P<0.01), and increased the absorption capacity of jejunal villi (P<0.01). Short-term fasting increased the expressions of anti-inflammatory factors IL-4 and IL-10 in jejunal mucosa (P<0.01). In addition, short-term fasting not only promoted the expressions of FFAR2 and NPY2R in NG (P<0.01), but also increased the expression of IL-4R (P<0.01).

Conclusion Starvation can increase the levels of intestinal anti-inflammatory factors, enhance intestinal barrier function, and promote the expressions of receptors such as vagal anti-inflammatory factors in yellow-feathered broilers.