title: High Amylose Starch with Low In Vitro Digestibility Stimulates Hindgut Fermentation and Has a Bifidogenic Effect in Weaned Pigs.
abstract: BACKGROUND
  Dietary amylose resists enzymatic digestion, thereby providing a substrate for microbial fermentation that stimulates proliferation of beneficial microbiota and production of short-chain fatty acids (SCFAs) in the large intestine of pigs and humans. However, the effect of increasing dietary amylose in pigs immediately postweaning on growth, nutrient digestibility and flow, and intestinal microbial and SCFA profiles has not been studied and can be used as a model for newly weaned human infants.
  
  
  OBJECTIVE
  We studied the effects of increasing dietary amylose on growth, nutrient digestibility, and intestinal microbial and metabolite profiles in weaned pigs.
  
  
  METHODS
  Weaned pigs (n = 32) were randomly allocated to 1 of 4 diets containing 67% starch with 0%, 20%, 28%, or 63% amylose for 21 d. Subsequently, pigs were killed to collect feces and digesta for measuring starch digestion and microbial and metabolite profiles.
  
  
  RESULTS
  Feeding weaned pigs 63% compared with 0%, 20%, and 28% amylose decreased (P < 0.05) feed intake by 5% and growth by ≥ 12%. Ileal digestibility of dry matter decreased (P < 0.05) by 10% and starch by 9%, thereby increasing (P < 0.05) hindgut fermentation, cecal and colonic total SCFAs, and colonic Bacteroides, and lowering (P < 0.01) ileal, cecal, and colonic pH in pigs consuming 63% compared with 0%, 20%, and 28% amylose. Cecal and colonic Bifidobacteria spp. increased by 14-30% (P < 0.05) and Clostridium clusters IV and XIVa were decreased (P < 0.01) in pigs consuming 63% compared with 0%, 20%, and 28% amylose.
  
  
  CONCLUSIONS
  Increasing dietary amylose in pigs immediately postweaning stimulated hindgut fermentation and Bifidobacteria spp., thereby manipulating the gut environment, but also reduced intake and growth. An optimum dietary amylose concentration should be determined, which would maintain desired growth rate and gut environment in weaned pigs.
authors.affiliation: University of Alberta, Edmonton, Alberta, Canada; and.
authors.forename: Janelle M
authors.initials: JM
authors.lastname: Fouhse
authors.affiliation: University of Alberta, Edmonton, Alberta, Canada; and.
authors.forename: Michael G
authors.initials: MG
authors.lastname: Gänzle
authors.affiliation: University of Alberta, Edmonton, Alberta, Canada; and.
authors.forename: Prajwal R
authors.initials: PR
authors.lastname: Regmi
authors.affiliation: North Carolina State University, Raleigh, NC.
authors.forename: Theo A T G
authors.initials: TA
authors.lastname: van Kempen
authors.affiliation: University of Alberta, Edmonton, Alberta, Canada; and ruurd.zijlstra@ualberta.ca.
authors.forename: Ruurd T
authors.initials: RT
authors.lastname: Zijlstra
mesh_terms: D000688:Amylose / Q000008:administration & dosage* / Q000737:chemistry; D000821:Animal Feed / Q000032:analysis; D000818:Animals; D001439:Bacteroides / Q000302:isolation & purification; D001644:Bifidobacterium / Q000302:isolation & purification; D002432:Cecum / Q000378:metabolism* / Q000382:microbiology; D004269:DNA, Bacterial / Q000235:genetics; D004032:Diet / Q000662:veterinary; D004063:Digestion; D005232:Fatty Acids, Volatile / Q000378:metabolism; D005243:Feces / Q000382:microbiology; D005285:Fermentation; D000069196:Gastrointestinal Microbiome; D018628:Gene Dosage; D016680:Genome, Bacterial; D023281:Genomics; D006863:Hydrogen-Ion Concentration; D007082:Ileum / Q000378:metabolism* / Q000382:microbiology; D013213:Starch / Q000008:administration & dosage* / Q000737:chemistry; D013552:Swine; D014886:Weaning
chemical_list: D004269:DNA, Bacterial; D005232:Fatty Acids, Volatile; D013213:Starch; D000688:Amylose
keywords: SCFA; amylose; bacteria; growth; pig; starch