The Use of daily postpartum rectal temperatures to select dairy cows for treatment with systemic antibiotics

Abstract

This retrospective study analysed descriptive statistics on daily rectal temperatures of 1042 dairy cows taken for 10 days postpartum on one farm in southeastern Pennsylvania, USA, from May 1998 to February 2000. Cows were classified as NORMAL if they did not have a retained placenta, dystocia, metritis, or mastitis event and received no systemic antibiotic treatment for the first 10 days postpartum. NORMAL cows had average daily temperatures below 102.0°F during days 1 through 10 postpartum. Cows with either retained placenta, metritis, dystocia or mastitis tended to have temperatures greater than 102.0°F during days 2 through 8 postpartum. All cows had the lowest temperatures during the first two days postpartum. Those requiring systemic antibiotic treatment had their highest temperatures on days 3 through 6 postpartum. Because there were no differences in daily postpartum temperatures of normal cows by lactation, the same criteria could be used to select primiparous and multiparous cows for treatment with systemic antibiotics. Finding one rectal temperature greater than 102.0°F or 102.5°F would not be sufficiently discriminating to decide to treat with antibiotics because 48% of NORMAL cows had at least one temperature greater than 102.5°F during the first ten days postpartum. Cows with average temperatures greater than 103.5°F had a significant average 1.0°F decline in temperature the day after systemic antibiotic treatment was started. Daily temperatures should be taken for at least seven days postpartum.