HISTOLOGY AND HISTOPATHOLOGY

From Cell Biology to Tissue Engineering

 

Effects of a probiotic on the morphology and mucin composition of pig intestine

Salvatore Desantis1, Maria Mastrodonato2, Gianluca Accogli1, Giacomo Rossi3 and Alberto Maria Crovace1

1Section of Veterinary Clinics and Animal Productions, Department of Emergency and Organ Transplantation (DETO), University of Bari "Aldo Moro", Valenzano, (Ba), 2Department of Biology, University of Bari "Aldo Moro", Bari and 3School of Biosciences and Veterinary Medicine, University of Camerino, Matelica, (MC), Italy

Offprint requests to: Salvatore Desantis, Section of Veterinary Clinics and Animal Productions, Department of Emergency and Organ Transplantation (DETO), University of Bari Aldo Moro, S.P. Casamassima Km 3, 70010 Valenzano (Ba), Italy. e-mail: salvatore.desantis@uniba.it


Summary. Although the use of probiotics in human and animal medicine is growing, their mode of action remains poorly understood. This study examined the effects of a multi-strain probiotic (SLAB51™) on the morphology and carbohydrate composition of mucins secreted by goblet cells of intestinal crypts in growing-finishing pigs. Sections of duodenum, caecum and colon from pigs fed for 12 weeks with an orally administered control basal diet (No-Pro) or one with a probiotic blend (Pro) were processed for microscopic analysis and stained with (1) haematoxylin-eosin for structural and morphometrical investigation; (2) conventional histochemistry (periodic acid-Schiff, Alcian Blue pH 2.5, high iron diamine staining) for neutral, acidic non-sulphated, and sulphated mucin analysis; and (3) FITC-labelled MAA-II and SNA lectins for α2,3- and α2,6-sialomucin identification. Compared with No-Pro samples, Pro samples displayed (1) increased goblet cell numbers in all investigated tract crypts; (2) an increase in acidic non-sulphomucins but a decrease in neutral, sulphated and α2,6-sialomucin-secreting goblet cells in the duodenum; (3) decreased crypt depth, an increase in α2,6-sialomucin secretory goblet cells, and a loss of goblet cell-secreting α2,3-sialomucins, which appeared on the apical surface of crypt fundus epithelial cells in the caecum; and (4) an increase in α2,6-sialomucin-producing goblet cells in the colon. Results suggest that treatment with SLAB51™ induces region-specific changes in the morphology and carbohydrate composition of mucins secreted along intestinal tracts of growing-finishing pigs. These changes could ameliorate the health status of the animals, which displayed higher growth performance and meat quality than controls (Tufarelli et al., 2017). Histol Histopathol 34, 1037-1050 (2019)

Key words: Mucins, Intestine, Glycohistochemistry, Probiotic, Diet, Swine

DOI: 10.14670/HH-18-106