Body Temperature and White Blood Cell Count in Postpartum Dairy Cows

Abstract

The objectives of this study were to evaluate rectal temperature as a diagnostic tool in postpartum dairy cows and to compare body temperature and white blood cell counts in cows that remained healthy with those that became ill. Fifty Holstein dairy cows had complete physical examinations every four hours and a complete blood count once daily for the first 10 days after calving. Illness was defined as a rectal temperature of at least 104.5°F (40.3°C) in the absence of other clinical signs, or a clinical sign of illness other than increased temperature. Fifteen cows were diagnosed with illness and 35 remained healthy throughout the 10-day study period. No difference between mean rectal temperatures of cows that became ill and cows that remained healthy was found. Among cows that remained healthy, 23 (66%) had a rectal temperature of at least 103.1°F (39.5°C) at least once, 17 (49%) had a rectal temperature of at least 103.5°F (39.7°C) at least once and six (17%) had a rectal temperature of at least 104°F (40°C) at least once during the study period. Over the first three days after calving, mean total white blood cell counts and neutrophil counts were higher in healthy cows than in cows that became ill. Because rectal temperatures were frequently elevated in healthy postpartum cows, it was concluded that rectal temperature has low specificity for diagnosing illness in postpartum dairy cows in the absence of other clinical signs.