To compare the susceptibility to acute rumen lactic acidosis (RLA) four Jersey (J) (Bos taurus) and four Gir (G) (Bos indicus) rumen-cannulated steers were used. In order to standardise the rumen microbiota, the steers were fed a standard diet of hay and concentrates, for two months before the beginning of the induction. The RLA was induced with sucrose administered intraruminally, on a basis of the corrected metabolic weight. Rumen fluid and faecal samples were collected throughout 24h after the induction. The pH and the concentration of total lactic acid and its L and D isomers were determined in all samples. Both breeds developed intense rumen acidosis; similar pH and concentration of total lactic acid and its isomers were found in the rumen fluid and faecal samples. The higher the total lactic acid concentration in the faeces, the lower the faecal pH (r = - 0.65). The faecal pH can be used as a tool to diagnosis RLA.
cattle; breeds; susceptibility; lactic acidosis; rumen; faeces
