The effect of ketoprofen administered in the early postpartum period on dairy cow health, production and reproduction.

Dairy cows undergo acute physiological changes over the transition from non-lactating and pregnant, through calving and initiation of lactation. Inflammation is necessary for adaption to these changes; however, excess inflammation in dairy cows is common and associated with poorer health, production and reproduction. Therefore, reducing inflammation at calving with non-steroidal anti-inflammatory drugs, such as ketoprofen, could reduce the negative consequences of inflammation. In this study, we recruited 1144 cows from five commercial dairy farms which were randomised to either receive one dose of ketoprofen 2-3 days postpartum or no treatment. The effect of ketoprofen on survival, number of treatments for disease, milk yield, days to conception and 21 other related health, production and reproduction parameters at 300 days in milk were tested using regression models. Ketoprofen treatment had no effect on the primary outcomes tested but had an effect on two associated outcomes, which is fewer than would be expected by chance. Therefore, there is little evidence overall of an effect of ketoprofen on health, production and reproduction. The effect with the most statistical support was that ketoprofen treatment was associated with a 0.05% (95% confidence interval 0.01-0.08%) increase in milk protein for multiparous cows. We did not replicate the findings of other ketoprofen clinical trials, which could be due to differences in timing and number of doses of ketoprofen, or findings not being generalisable across farms. Future studies should investigate the effect of ketoprofen timing and course duration and test the replicability of our findings.