The temperature of 90 dairy cattle was recorded for the first 10 days after parturition and the animals were categorised as either normal (<39.7°C) or pyrexic. Swabs were collected from the uterine lumen seven, 14, 21 and 28 days after parturition for aerobic and anaerobic culture; bacteria were identified and their growth was scored semiquantitatively. Blood samples were collected three times a week for the estimation of the concentrations of acute phase proteins. The cows' temperatures were often above the accepted normal range, but it was not a good indicator of the number of bacteria in the uterus. However, pyrexia was correlated with the presence of specific uterine pathogens (P<0.05) and in particular with Prevotella species (P<0.01). The pyrexic animals had a higher plasma concentration of the acute phase protein (α1-acid glycoprotein (P<0.05). Although pyrexia is an indicator of postpartum inflammation, additional clinical signs are necessary to identify uterine bacterial infection.