Approche quantitative de l'acidose chez les ruminants

The rumen acidosis is a common disease in high producing ruminants which received, then, a high-energy diet. This pathology is increasingly studied and many results are now available. These data were used to establish rumen pH response laws to various factors, linked with either feeding practices or not, which allow to deduce threshold values and ranges of optimum values for various criteria. The available results and the established models were considered first from a static point of view and then from a dynamic one. On this last aspect, interesting relationships were established between the dynamics of feeding behavior and pH. Moreover, bouts of acidosis altered rumen function only moderately and more severely intake and milk production with a long delay of recovery. Nowadays, promising research focused on acidosis deals with relationships between the characteristics of the rumen microbiota and its host.