Influence on thiamine metabolism and fermentation in bovine rumen fluid (in vitro)

The influence of sodiumsulfite on the in-vitro-fermentation especially the thiamine metabolism of bovine rumen fluid was investigated using the long t erm rumen simulation technique (RUSITEC). Five investigation periods lastin g 25 days each were carried out. After a control period of nine days two fi ve day testphases followed. During this time two reaction vessels were char ged with (FSA) and two without (KF) sulfite, in the second testphase all ve ssels were additionally charged with thiamine (0.3 mg each vessels five day s long). The following effects of sulfite and sulfite/thiamine supplementat ion could be noted: total sVFA-concentrations rested unchanged but the rela tionship between changed: acetate-: -9,9 to -17,6%, propionate-: +6,29 to 8 ,57%, i-butyrate-: +5,88 to 9,30%, n-butyrate-: +16,3 to 23,6%, i-valeriani c-: -32,2%, n-valerianic-: +32 to 86%, hexanicacid: +31 to 66%. Gases: meth ane-: -60%, hydrogen production: +700%. N-metabolism: protein concentration : +32%. Thiamine in the overflow: +3,23 to 6,78% (testphase I), - 8,33% (te stphase II), Using this experimental design (RUSITEC) and the determined pa rameters (thiamine etc.), no evidence was found in respect to the developme nt of CCN/PEM.