title: In vitro effects of sodium bicarbonate buffer on rumen fermentation, levels of lipopolysaccharide and biogenic amine, and composition of rumen microbiota.
abstract: BACKGROUND
  Diets containing high levels of carbohydrates provoke a rapid decrease of rumen pH and high levels of biogenic amines and lipopolysaccharides (LPS), which severely impair the health and performance of ruminants. The goal of this study was to evaluate the effects of sodium bicarbonate (BC) buffer on rumen fermentation, levels of LPS and biogenic amine, and composition of rumen microbiota using in vitro rumen cultures.
  
  
  RESULTS
  Sodium bicarbonate supplementation increased (P < 0.05) the final pH levels and concentrations of total volatile fatty acids and LPS, as well as the proportions of acetate, propionate, isobutyrate, isovalerate and valerate, and it decreased (P < 0.05) the proportion of butyrate and the levels of lactic acid, methylamine, tryptamine, tyramine, histamine and putrescine compared with the control. Pyrosequencing of the 16S rRNA gene showed that BC inclusion increased (P < 0.05) the bacterial diversity index compared with the control. Adding BC also decreased (P < 0.05) the relative abundance of Streptococcus and Butyrivibrio and increased (P < 0.05) the proportions of Ruminococcus, Succinivibrio and Prevotella.
  
  
  CONCLUSIONS
  Sodium bicarbonate supplementation has beneficial effects in the reduction of bioamine levels and the increase in ruminal pH, and in modifying the microbial ecology of the rumen; however, it results in an accumulation of LPS under high-grain diet conditions. © 2016 Society of Chemical Industry.
authors.affiliation: College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, 210095, China.
authors.forename: Shengyong
authors.initials: S
authors.lastname: Mao
authors.affiliation: College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, 210095, China.
authors.forename: Wenjie
authors.initials: W
authors.lastname: Huo
authors.affiliation: College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, 210095, China.
authors.forename: Junhua
authors.initials: J
authors.lastname: Liu
authors.affiliation: College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, 210095, China.
authors.forename: Ruiyang
authors.initials: R
authors.lastname: Zhang
authors.affiliation: College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, 210095, China.
authors.forename: Weiyun
authors.initials: W
authors.lastname: Zhu
mesh_terms: D000821:Animal Feed; D000818:Animals; D001419:Bacteria / Q000187:drug effects* / Q000254:growth & development / Q000378:metabolism; D044822:Biodiversity; D001679:Biogenic Amines / Q000378:metabolism*; D002021:Buffers; D002417:Cattle; D004032:Diet; D019587:Dietary Supplements; D005232:Fatty Acids, Volatile / Q000378:metabolism*; D005260:Female; D005285:Fermentation; D000069196:Gastrointestinal Microbiome / Q000187:drug effects*; D006863:Hydrogen-Ion Concentration; D066298:In Vitro Techniques; D008070:Lipopolysaccharides / Q000378:metabolism*; D064307:Microbiota; D012417:Rumen / Q000378:metabolism / Q000382:microbiology; D017693:Sodium Bicarbonate / Q000494:pharmacology*
chemical_list: D001679:Biogenic Amines; D002021:Buffers; D005232:Fatty Acids, Volatile; D008070:Lipopolysaccharides; D017693:Sodium Bicarbonate
keywords: biogenic amine, microbiota; lipopolysaccharides; sodium bicarbonate