The Beef Cattle Research Council has updated the pain mitigation section of its website. The following is an edited version of that page, which also contains videos and links to further articles.
Consumer pressure to avoid painful practices on cattle when possible — and to reduce pain when castration, dehorning, or branding are necessary — is building.
The knowledge of pain in livestock has advanced steadily over the past 22 years. Behavioural and physiological indicators of pain have been identified, and researchers’ ability to measure animal responses associated to painful procedures has improved. Research has developed new pain control drugs that are registered for use in cattle in Canada, and knowledge is building on the appropriate dosage, routes of administration, and synergy between anesthetics and analgesics.
Despite a considerable amount of research, cattle’s experience with pain is not fully understood. Research that has used electroencephalographs to monitor brainwaves in cattle during painful practices detects clear differences, so it is clear that cattle experience pain. However, as prey animals, cattle have evolved to not show behavioural signs of pain, which is a sign of weakness to predators.
Most previous research into pain control for castration and dehorning has been done in dairy calves that were weaned at birth, or in feedlot calves. Little or no research has been done in young beef calves in a herd environment. Therefore, it’s unknown whether the relief that beef calves get when they return to their mothers and nurse may also help to eliminate pain-associated behaviours.
Many past studies have used drugs in ways that are difficult to implement in commercial practice. Some have used elaborate combinations of drugs, some of which are not licensed for use in cattle, or used experimental formulations that are not commercially available (e.g. oral meloxicam). Other experiments have repeatedly given the pain drugs over several days, requiring additional handling, stress, and risk of injury for the cattle.
Currently pain in animals can only be routinely measured using behavioural and physiological responses. Depending upon the management procedure being evaluated, researchers have used standing, lying, feeding, ruminating, kicking, tail-flicking, ear-flicking, pacing posture, and weight-shifting behaviours to gauge animal responses to painful practices and pain control. Acute, immediate pain is easier to measure than chronic, long-term pain (lasting more than three days).
Researchers have found that dehorned calves do more head rubbing, head shaking and ear flicking than calves that have not been dehorned. Castrated calves stand, move and lie differently than calves that have not been castrated. Pain drugs alter these behavioural differences; feedlot bulls that are castrated using pain drugs show fewer of these abnormal, pain-related behaviours.
In Canada, the most common routine management procedures that cause pain are castration, dehorning, and branding.
All methods of castration are painful. Surgical castration causes more intense pain that lasts for a few days, while banding castration causes a less intense but chronic pain that lasts for more than one month.
It is strongly recommended that cow-calf producers castrate calves as young as possible. Castration of bull calves soon after birth results in improved health and gain in the feedlot, and enhanced carcass marbling and tenderness compared to castration at or after weaning. Animal health and welfare risks, and animal performance impacts all increase with age.
The Beef Code of Practice requires castration be performed by competent personnel using proper, clean, and well-maintained tools, and that animals be castrated as young as practically possible, before the age of three months and especially before weaning. As of 2016, pain control will be required when castrating bulls older than nine months. In 2018, that will drop to six months.
Dehorning can be reduced through genetics. Research into the performance of polled versus horned bulls of many different breeds has shown no differences in any production performance measures.
Horns are a shell made of keratin and other proteins over a core of living bone. Dehorning decreases the risk of injury for both handlers and other cattle, and minimizes the economic loss due to carcass bruising. In addition to training and proper tools, the beef code will require, beginning in 2016, pain control in consultation with your veterinarian when dehorning after the horn bud has attached.
In Canada, the incidence of branded beef cattle is continually decreasing. The most recent National Beef Quality Audit found that the use of brands dropped from 25 per cent of fed cattle in 1999 to less than 10 per cent in 2011.
Both hot and freeze branding can be used as forms of permanent identification. Although both types of branding are known to cause pain, it has been shown that hot branding causes more acute pain at the time of the procedure. Freeze branding can only be done on dark-coloured cattle and is more difficult to do properly.
Currently there is no practical way to give pain control drugs when branding.
Pain control drugs
Few pain control options are commercially available for cattle, and all require a veterinary prescription. Anesthetic and analgesic drugs can help control pain. Anesthetic drugs (like freezing at a dentist) eliminate all feeling while anesthetics (e.g. Lidocaine) help to reduce the pain of surgery, but wear off relatively quickly and are challenging to use.
Analgesics (e.g. Metacam, Anafen and Banamine) may be a better option for cattle producers. These don’t eliminate all feeling, but do reduce the pain that occurs after the surgery. They can be injected intramuscularly or through intravenous methods and last longer than anesthetics.
A number of analgesic drugs have been approved for use in beef cattle. None of these products have a specific claim for pain control following castration, and few are approved for pain control during dehorning. But they do control swelling and pain for a variety of different conditions.
Research shows that a combination of anesthesia and analgesia provides the best pain control.
Age of animal
Procedures are much less invasive in young animals. The wound is smaller, there is considerably less blood loss, and young calves recover more quickly with a smaller setback in animal performance.
Although research is still being conducted in this area, it is suggested that to reduce pain, procedures should be conducted when animals are as young as possible, especially when dehorning because the horn bud attaches at two to three months of age.
Painful procedures should not be performed during times when the animal will be experiencing other stressors (e.g. don’t castrate at the same time as weaning). Stress reduces the animal’s immune system and makes them less able to fight off infection.
Euthanasia is defined as the humane death of an animal without inflicting pain or distress using methods that cause an immediate loss of consciousness followed by cardiac and respiratory arrest and death without a return to consciousness.
Having a euthanasia decision-making process in place on your farm, along with proper training in both determining when euthanasia should occur and proper procedure will help to minimize unnecessary pain and distress in animals.
The Beef Code of Practice requires that animals be immediately euthanized (or culled with proper adherence to the requirements for transporting compromised cattle) if they:
- Have chronic, severe, or debilitating pain and distress;
- Are unlikely to recover;
- Have failed to respond to treatment or recovery protocols;
- Are unable to get to or consume food and water;
- Show continuous weight loss or emaciation.
Despite some advances in understanding pain in cattle, there is still much we do not understand when it comes to the effect and management of pain-associated procedures like castration and dehorning.
Research under the second Beef Science Cluster is currently evaluating the relative impacts of age, technique, and pain medication when pre-weaning beef calves are castrated at the same time as branding or as a separate procedure. This research will generate science-based recommendations regarding the best age to carry out painful routine management procedures and identify target ages which may require pain mitigation.