Modulation of Morphology and Glycan Composition of Mucins in Farmed Guinea Fowl (Numida meleagris) Intestine by the Multi-Strain Probiotic Slab51(®)

SIMPLE SUMMARY: In the poultry industry, several studies demonstrate the positive effects of probiotic administration on induction of intestinal gene expression, physiology, immunology, morphology and mucus composition. The mucus layer covers the epithelium of the gastrointestinal mucosa, protects it against physical and chemical injuries caused by food, microbes adhesion, and microbial metabolites, promotes the gut content elimination and modulates water and electrolyte absorption. Mucins are glycoproteins that play a key role in constituting the intestinal mucus layer, and their production takes place in the goblet cells. This study examined the effects of the multi-strain probiotic Slab51(®) on the morphology and carbohydrate composition of intestinal glycoproteins of 40 guineafowl (Numida meleagris), averagely weighing 110 ± 0.99 g, during a grow-out cycle that lasted 120 days. Samples from different anatomical tracts of intestine, collected after slaughtering, were processed for morphological, morphometric, conventional and lectin glycohistochemical studies. Compared with control samples, probiotic group revealed significant increase in morphological parameters and goblet cells expression per villus in all investigated tracts as well as region-specific changes in carbohydrate composition of glycoproteins of the mucus layer. ABSTRACT: Probiotics have become highly recognized as supplements for poultry.Since gut health can be considered synonymous withanimal health, the effects of probiotic Slab51(®) on the morphology and the glycan composition of guineafowlintestine were examined. The probiotics were added in drinking water (2 × 10(11) UFC/L) throughout the grow-out cycle.Birds were individually weighed andslaughtered after four months. Samples from the duodenum, ileum and caecum were collected and processed for morphological, morphometric, conventional and lectin glycohistochemical studies.The results were analyzed for statistical significance by Student’s t test. Compared with control samples, probiotic group revealed (1) significant increase in villus height (p < 0.001 in duodenum and ileum; p < 0.05 in caecum), crypt depth (p < 0.001 in duodenum and caecum; p < 0.05 in ileum) and goblet cells (GCs) per villus (p < 0.001) in all investigated tracts; (2) increase in galactoseβl,3N-acetylgalacyosamine(Galβl,3GalNAc)terminating O-glycans and αl,2-fucosylated glycans secretory GCs in the duodenum; (3) increase in α2,6-sialoglycans and high-mannose N-linked glycans secretory GCs but reduction in GCs-secreting sulfoglycans in the ileum; (4) increase in Galβl,3GalNAc and high-mannose N-linked glycans secretory GCs and decrease in GCs-producing sulfomucins in the caecum; (5) increase in the numbers of crypt cells containing sulfate and non-sulfated acidic glycans. Overall, dietary Slab51(®) induces morphological and region-specific changes in glycoprotein composition of guinea fowl intestine, promoting gut health.