The effects of flunixin meglumine and hoof trimming on lying behavior, locomotion, and milk production in lame and nonlame lactating dairy cows.

Hoof trimming is used to prevent and treat lameness in dairy cows; however, hoof trimming itself increases daily time spent lying down, possibly due to discomfort. We hypothesized that treatment of lame and nonlame cows with an anti-inflammatory analgesic drug at the time of hoof trimming would mitigate discomfort, thereby improving locomotion scores and reducing post-trimming increases in lying time. We further hypothesized that drug treatment would improve post-trimming milk production. Our objective was to determine the effects of treatment with the nonsteroidal anti-inflammatory drug flunixin meglumine (2.2 mg/kg of BW) at the time of hoof trimming on locomotion, lying times, and milk production in lame and nonlame lactating dairy cows. All cows were filmed for locomotion scoring 1 d before and 1, 8, and 28 d after hoof trimming. Daily time spent standing and lying was recorded for 4 d before and 4 wk after hoof trimming, and daily milk production was recorded for 1 wk before and 8 wk after trimming. Thirty minutes before hoof trimming, an intravenous injection of flunixin meglumine (n = 34) or isotonic sterile saline solution (n = 34) was administered to each cow. Then, all cows had their hooves trimmed using the Dutch method. The same treatment was repeated 24 h after hoof trimming. Cows were categorized using baseline locomotion scores as lame (score ≥3/5) or nonlame (score <3/5). Drug treatment did not affect post-trimming changes in locomotion scores, daily lying times, or milk production. In both treatment groups, most cows had the same lameness status (lame or nonlame) at baseline and after treatment, and there was no difference between groups in the number of cows that changed lameness status over time. Lame cows (n = 21) had no significant changes in lying times over the course of the study, whereas nonlame cows (n = 47) had mean daily lying times that were significantly higher than baseline all 4 wk after trimming. Hoof trimming in nonlame cows should be scheduled for a time when increased lying behavior after trimming can be accommodated.