Feed additives influence goblet cell distribution and villus-crypt architecture in broilers after necrotic enteritis challenge

The probiotic, Lactobacillus johnsonii and a commercial organic acid (OA) blend were histologically evaluated as potential non-antibiotic preventatives for necrotic enteritis (NE). A total of 1200 Cobb 500 broilers were randomly assigned to the following six treatment groups; unchallenged (Control), Clostridium perfringens challenged (Cp), zinc bacitracin (ZnB), organic acid (OA), vehicle and L. johnsonii (Lj) (n=25 birds/pen, 8 pens/treatment). All treatment groups with the exception of the Control group were challenged with C. perfringens (Cp). Histological examination revealed that OA and Lj were unsuccessful in preserving intestinal architecture, however ZnB maintained villus:crypt structure comparable to the Control group. Total goblet cell (GC) number/mm villus surface length was not significantly different amongst any of the dietary treatment groups. No interactions between dietary treatment and mucin type were observed. The number of neutral mucin containing GC was significantly greater in comparison to the number of total acidic mucin containing GC in all dietary treatment groups. Cp challenge did not appear to affect the number of neutral or acidic mucin GC however ZnB decreased the number of both neutral and total acidic mucin GC. No significant differences in acidic mucin subtypes (sulphated, sialylated and intermediate) were observed amongst dietary treatments. Sulphated mucin containing GC were the dominant subtype within all treatment groups. Understanding how Cp affects the intestinal wall will assist in the search for NE preventatives.