Some people cringe at the thought of going to the dentist. In the lyrics of a country song released last year, the singer tells how his dentist started drilling before he was numb. Meanwhile, he tries to block out the pain by envisioning himself on “some beach, somewhere.”
Maybe you can relate.
If you don’t use pain control during dehorning, your calves may be thinking that same thing. And they’re probably not alone. According to a survey of 300 Canadian producers in Ontario, only 25 percent of them used a local block during dehorning, says Todd Duffield, veterinarian at the University of Guelph in Canada.
Research shows calves feel pain during and after dehorning — not to mention the stress that comes with additional handling and restraint. Here’s why you should take measures to control pain during the dehorning process.
Pain control works
It’s obvious to anyone who has dehorned calves that they experience pain during and after the procedure. Even caustic-paste dehorning, which is potentially less invasive than either hot-iron dehorning or scoop dehorning, comes with its share of discomfort.
In one of the most recent studies done on dehorning, University of British Columbia researchers found that pain-related behaviors, such as head-shaking and head-rubbing, increased in calves when they were dehorned using caustic paste compared to when they were “sham” dehorned about a week earlier; that is, when they were handled in an identical manner, but were not actually dehorned.
Results from that study, which appeared in the April Journal of Dairy Science, also show that a sedative was effective at reducing pain after caustic-paste dehorning. (For more details, please see “What’s the best method of pain control?” on page 58.) The sedative also eliminated the need for physical restraint during the procedure, thus reducing stress even further.
Another Canadian study, presented this summer at the annual meeting of the American Dairy Science Association, also shows pain control works during hot-iron dehorning.
“We found significantly less behavioral responses (like foot-stamping) in lidocaine-blocked calves than calves that were not blocked,” Duffield says. Heart rate also was significantly lower in calves that were blocked.
Other work by Duffield’s group at the University of Guelph shows that ketoprofen, a non-steroidal anti-inflammatory drug, alleviated pain following hot-iron dehorning, particularly in older calves that were dehorned after four weeks of age. If you dehorn calves before four weeks of age, an anti-inflammatory probably isn’t necessary, Duffield adds. That’s good, because it adds about $1.25 more per calf to your treatment cost.
Minimal investment needed
Unless you add a non-steroidal anti-inflammatory drug to the mix, you can keep the cost of pain control at $1 or less per calf. That includes a local anesthetic, such as lidocaine, and a sedative, such as xylazine. Cut that cost at least in half if you use just one or the other. It also depends on the volume you purchase and the dose used.
Now granted, you will need to train someone — with your veterinarian’s help — to administer the pain-control products. However, once you teach someone the proper technique, “it’s learned fairly quickly,” Duffield says. And in most cases, it takes only five to 10 minutes for a sedative or local anesthetic to take effect.
And, if the calf has been sedated, you may only need one person to perform the dehorning.
Although dehorning is a necessary procedure to protect both animals and humans, the general public doesn’t necessarily see it that way. They see an animal in pain, and that’s not acceptable.
Indeed, dehorning pain control is one of the topics identified as a “best management practice” in the Dairy Quality Assurance guidelines. It also has surfaced in animal-welfare assessment and audit programs. These programs evaluate the animal-care practices on your farm from the viewpoint of someone who’s on the outside looking in. (For more details, see “What do your cows say about their welfare?” on page 24 in the August issue.)
For example, the Animal Welfare Assurance Review and Evaluation (AWARE) program recommends that dehorning occur between two and 10 weeks of age. The questionnaire used by auditors with the program asks whether or not you use a local anesthetic if dehorning takes place after 10 weeks of age.
Although still voluntary, these programs were designed, in part, to reassure consumers that humane animal-care practices are used on farm.
At a calf-and-heifer conference held earlier this year, Dan Weary, professor and co-founder of the Animal Welfare Program at the University of British Columbia, summed up the issue of dehorning pretty well when he said: “Here’s something that has the potential to give our industry a black eye.”
Don’t let it get that far. Use pain control when dehorning calves.
What’s the best method of pain control?
The research is still a work in progress, but here’s what researchers know so far about pain control for caustic-paste and hot-iron dehorning — two of the most common techniques used on farm. Talk to your veterinarian about which pain-control method is right for you.
Several studies show that a local anesthetic controls the pain well during the procedure. Longer-acting local anesthetics and non-steroidal anti-inflammatory drugs alleviate pain following the procedure. A sedative helps minimize distress during physical restraint.
Caustic paste dehorning
Less is known about pain control during and after caustic-paste dehorning. However, research in the April Journal of Dairy Science shows that a sedative alone may be your best choice. As the chart below shows, calves given a sedative and a local anesthetic actually shook and rubbed their heads more during the first four hours after dehorning than calves given only a sedative. The study’s authors aren’t really sure why the anesthetic didn’t work well, but speculate that the chemical make-up of the caustic paste interfered with the function of the anesthetic, making it fairly ineffective.