Using a pain reliever like Meloxicam should be a consideration for dairy producers.
By: David Wilson, Extension Veterinarian, Utah State University
Analgesia for dehorning calves has been a somewhat controversial subject since I can remember. We learned in vet school about lidocaine infiltration with needles including nerve blocks and/or whether initially intended or not (in the case of a nerve block that did not really find the nerve) subcutaneous administration around the base of the horns. This took time, expense, and many owners said it seemed like it bothered the calf as much as the dehorning itself. When I dehorned dairy animals in practice, including as an Ambulatory Resident at Michigan State, we rarely used any analgesia. Many surveys and discussions at veterinary conferences confirm that this was the common way to do it, and seems to still be the case now according to recent data. I remember a colleague telling me that he liked the cold spray-on fast acting local anesthetics like Pontocaine, so he decided to try it for electrical hot dehorning. He sprayed it around the horns of the first calf, started dehorning and flames lit up. They were quickly blown out without apparent major damage but this spectacular display led to no more using the spray after a sample of one calf.
It was also true that the vast majority of bovine dehorning I did in practice was not on calves with small horn buds. Most owners used caustic paste, an electric (“hot iron”) dehorner, a tube dehorner, or a small Barnes dehorner to do their own dehorning if the animals to be dehorned were young calves. I always liked it if as part of calfhood vaccination and extra teat removal, I was doing that kind of dehorning. However, much of the dehorning I did was when for whatever reason, whether it was purchased animals that were not dehorned, or that the farm labor force did not get to it on young calves, we had to remove moderately large to huge horns. The large Barnes, electrical saw, or most commonly, Keystone (the large ones with two handles similar to wooden baseball bats) dehorners were the tools of the day. Pulling arteries with a needle nose pliers (I found that they worked better than box-lock hemostats that would get sprung) and spraying and packing or using Pine Tar (that really helped keep flies and maggots out) on the open cornual sinus was what came next.
I often wonder what the solution is today when for whatever reason, a dairy has a large number of animals with large horns to dehorn. Practicing vets don’t seem to be as involved, or if they are they are not saying much about it at conferences because today we are all supposed to be herd health consultants and not do so much “fire engine” work. Veterinarians are still involved in either dehorning or teaching farm employees to dehorn at least the young calves, though. It seems that we may have a relatively new practical way to produce fairly long-acting analgesia for calves after dehorning and castration, and also for cows following surgery, dystocia, or sometimes to help with lameness or injuries. This is in the form of meloxicam, an NSAID that is available in 15 mg tablets. The tablets cost approximately 3 cents apiece. The dose is 1 mg/kg (0.45 mg/lb).
Meloxicam tablets inside gel capsules
A colleague told me that they use 4 tablets (60 mg, enough for up to 60 kg, 132 lb of body wt) inside a small gel capsule P.O. per calf. Some veterinarians administer local anesthesia as well at the time of dehorning, and as it wears off, the meloxicam takes effect. Sometimes the farm personnel give the calf another dose of 4 tablets either the next day or after two days. The same colleague also administers 40 tablets (600 mg, enough for up to 600 kg, 1320 lb of body wt) inside a large gel capsule P.O. per cow for pain relief following surgery, dystocia, etc. Again, sometimes this is repeated every one or two days by the farm personnel.
Meloxicam meat and milk withdrawal
Hans Coetzee, formerly of Kansas State University and now at Iowa State University, has conducted much of the research on meloxicam in cattle. He recommends a meat withdrawal of 21 days and a milk withdrawal of 96 hours following meloxicam administration. Interestingly, the meat withdrawal research was based on a dose of 0.5 mg/kg instead of the dose of 1 mg/kg. As with any medication, including just about any drug administered to dairy cattle, there is not much information regarding how many subsequent doses at what time intervals, or what the impact of low body weight cows who might be administered the standard dose of 40 tablets would be regarding the withdrawal time after the final dose. FARAD could probably help with this question if they were provided specific information. Meloxicam seems to be an affordable and practical way that we can provide analgesia to dairy animals; maybe it will become widely adopted.