title: Dietary calcium phosphate content and oat β-glucan influence gastrointestinal microbiota, butyrate-producing bacteria and butyrate fermentation in weaned pigs.
abstract: This study aimed to evaluate the effects of oat β-glucan in combination with low- and high-dietary calcium phosphate (CaP) content on gastrointestinal bacterial microbiota, prevalence of butyrate-production pathway genes and fermentation end-products in 32 weaned pigs allocated to four diets: a cornstarch-casein-based diet with low [65% of the calcium (Ca) and phosphorous (P) requirement] and high CaP content (125% and 115% of the Ca and P requirement, respectively); and low and high CaP diets supplemented with 8.95% of oat β-glucan concentrate. Pigs were slaughtered after 14 days, and digesta were collected for quantitative PCR analysis, and quantification of short-chain fatty acids and lactate. The high CaP content reduced gastric lactate and streptococci and propionate in the large intestine. Oat β-glucan distinctly raised gastric bacterial numbers, and colonic lactobacilli and bifidobacteria. Although not reflected by gene copies of butyrate-production pathway genes, oat β-glucan also increased gastric, caecal and colonic butyrate concentrations, which may be favourable for intestinal development in weaned pigs. Thus, a high CaP content negatively affected the intestinal abundance of certain fermentation end-products, whereas oat β-glucan generally enhanced bacterial numbers and activity. The results emphasize the importance of the stomach for bacterial metabolism of oat β-glucan in weaned pigs.
authors.affiliation: Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, AB, Canada. metzler@fbn-dummerstorf.de
authors.forename: Barbara U
authors.initials: BU
authors.lastname: Metzler-Zebeli
authors.forename: Ruurd T
authors.initials: RT
authors.lastname: Zijlstra
authors.forename: Rainer
authors.initials: R
authors.lastname: Mosenthin
authors.forename: Michael G
authors.initials: MG
authors.lastname: Gänzle
mesh_terms: D000818:Animals; D018554:Avena / Q000378:metabolism; D001419:Bacteria / Q000145:classification / Q000235:genetics / Q000378:metabolism*; D002087:Butyrates / Q000378:metabolism*; D002130:Calcium Phosphates / Q000378:metabolism*; D002136:Calcium, Dietary / Q000378:metabolism*; D004032:Diet / Q000662:veterinary; D005232:Fatty Acids, Volatile / Q000032:analysis; D005285:Fermentation; D005766:Gastrointestinal Contents / Q000737:chemistry / Q000382:microbiology; D041981:Gastrointestinal Tract / Q000382:microbiology*; D018628:Gene Dosage; D019344:Lactic Acid / Q000032:analysis; D015999:Multivariate Analysis; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D011897:Random Allocation; D013552:Swine; D014886:Weaning; D047071:beta-Glucans / Q000378:metabolism*
chemical_list: D002087:Butyrates; D002130:Calcium Phosphates; D002136:Calcium, Dietary; D005232:Fatty Acids, Volatile; D012336:RNA, Ribosomal, 16S; D047071:beta-Glucans; D019344:Lactic Acid; C020243:calcium phosphate