The aim is to improve the prediction of the formation of volatile acids from the rumen and of the transport and the metabolism of volatile fatty acids during transport. These prediction are relevant with respect to the amounts and the type of nutrients available for the dairy cow ( in particular glucogeneic versus ketogenic).
[Results]:
The main causes of inaccurate prediction of volatile fatty acids is 1) inaccuracy ot he linetics of absorption from the rumen and 2) the stoichiometry of the formation of volatile fatty acids from fermented substrate. A new stoichiometry was etimated from in vivo data of latating diary cows only, which differed substanstially from prevision results in literature. Further, a mechanism of competitive inhibition among individual types of volatile acids was represented in order to explain interactions in their transport, metabolism and appearance in portal blood. |
