Intestine Health and Barrier Function in Fattening Rabbits Fed Bovine Colostrum

Abstract

The permeability of the immature intestine is higher in newborns than in adults; a damaged gut barrier in young animals increases the susceptibility to digestive and infectious diseases later in life. It is therefore of major importance to avoid impairment of the intestinal barrier, specifically in a delicate phase of development, such as weaning. This study aimed to evaluate the effects of bovine colostrum supplementation on the intestinal barrier, such as the intestinal morphology and proliferation level and tight junctions expression (zonulin) and enteric nervous system (ENS) inflammation status (through the expression of PGP9.5 and GFAP) in fattening rabbits. Rabbits of 35 days of age were randomly divided into three groups (n = 13) based on the dietary administration: commercial feed (control group, CTR) and commercial feed supplemented with 2.5% and 5% bovine colostrum (BC1 and BC2 groups, respectively). Rabbits receiving the BC1 diet showed a tendency to have better duodenum morphology and higher proliferation rates (p < 0.001) than the control group. An evaluation of the zonulin expression showed that it was higher in the BC2 group, suggesting increased permeability, which was partially confirmed by the expression of GFAP. Our results suggest that adding 2.5% BC into the diet could be a good compromise between intestinal morphology and permeability, since rabbits fed the highest inclusion level of BC showed signs of higher intestinal permeability.

Bovine Colostrum Supplementation in Rabbit Diet Modulates Gene Expression of Cytokines, Gut–Vascular Barrier, and Red-Ox-Related Molecules in the Gut Wall

“…B-catenin is fundamental for the homeostasis of the gut, in particular for the renewal of the gut epithelium and for the activity of the gut vascular barrier [57,58]. This suggests that 5% BC supplementation could help the homeostasis of the gut also through the Wnt/b-catenin signaling pathway, according to the results shown by Aidos et al 2023 [59]. To evaluate intestinal inflammation, it is well established that the enteric nervous system can be used as an indicator of intestinal activation via glial cells [60].…”

“…To evaluate intestinal inflammation, it is well established that the enteric nervous system can be used as an indicator of intestinal activation via glial cells [ 60 ]. In a recent study of our group, we investigated the effect of bovine colostrum in rabbit gut health: an evaluation of zonulin expression, a junctional protein whose function is to prevent leakage of solutes and water and seals between the epithelial cells, showed that it was higher in the BC 5% group, suggesting increased permeability, which was partially confirmed by the increased expression of GFAP (glial fibrillary acidic protein), a marker of intestinal glial cell, but this result was limited to the duodenum [ 59 ].…”