Make sure you’re euthanizing your cows using the latest guidelines
It’s a sad fact of dairy life that cows sometimes must be euthanized. They break a leg or hip, encounter calving complications or fail to respond to treatment after falling ill. If your vet isn’t readily available, it’s up to you and your farm staff to euthanize the animal when its pain and suffering can’t be alleviated.
There are not only right and wrong ways to euthanize dairy cows, but the guidelines for humane killing were recently revised, say Jan Shearer of Iowa State University College of Veterinary Medicine and James Reynolds of Western University College of Veterinary Medicine.
Both veterinary professors served on an American Veterinary Medical Association (AVMA) panel that oversaw and revised protocols for euthanasia of cattle and small ruminants. Members of the AVMA Panel on Euthanasia’s Food Animal Working Group also included veterinarians Glen Johnson of Reedsburg, Wis., and Dee Griffin of the University of Nebraska.
"Two very important things came out of the AVMA euthanasia guidelines revision," Reynolds says.
First, he says, the recommended placement for the gunshot or captive bolt has been moved up toward the poll, or higher in the center of the forehead. "The original placement in the center of an X drawn between the eyes and ears was too rostral, or too far forward toward the nose, and tended to miss the brain and enter the frontal sinus," Reynolds says. Instead, make a line from the outside corner of each eye to the base of the opposite horn and aim the firearm or place the captive bolt on the intersection of these two lines.
Second, a .22 caliber firearm is not recommended for routine use in the euthanasia of adult cattle.
Instead, "larger caliber firearms are preferred," says Shearer, who chaired the AVMA committee.
Five years in the making, the revised euthanasia guidelines were adopted by AVMA last fall and are expected to be published online during the first quarter of 2012.
AVMA has classified euthanasia techniques as "acceptable," meaning methods that consistently produce a humane death when used as the sole means of euthanasia; and "acceptable with conditions," meaning methods that require certain conditions to be met to consistently produce a humane death. These may carry greater potential for human error or safety hazard and may require a secondary step to ensure death.
"Although some may misinterpret the classifications of ‘acceptable’ and ‘acceptable with conditions,’ it is important that people understand that methods in the latter category are considered to be equivalent to those in the ‘acceptable’ category and are totally acceptable, as long as they are done correctly," Shearer says.
AVMA considers injecting barbiturates and barbituric acid derivatives as "acceptable" for euthanizing dairy cattle. The cost of this method, however, can deter producers, particularly when large numbers of animals must be euthanized. In addition, administration must be done by a veterinarian registered with the U.S. Drug Enforcement Administration. Carcass disposal is then complicated by drug residue. Carcasses not disposed of properly may pose risks for wildlife that consume the body.
The most common method for on-farm cattle euthanasia is the gunshot, which AVMA deems "acceptable with conditions." When properly directed, a bullet, birdshot from a shotshell or slug will cause massive brain destruction and immediate loss of consciousness and death.
For euthanasia by firearm, operators are advised to never place the muzzle of the gun against the cow’s head. "Proper placement of the bullet is essential and best achieved by holding the firearm, when possible, within 2' to 3' of the intended target," Shearer says.
The AVMA committee advocates the use of solid-point bullets. "Hollow-point bullets are designed to fragment on impact and may not penetrate the skull, thus limiting brain destruction," Shearer adds.
If a penetrating captive bolt is used to euthanize a dairy cow, make sure it’s done properly, with good restraint of the animal’s head. Unlike a firearm, the muzzle of a captive bolt gun must be held flush with the skull. Powder-activated guns are available in 9 mm, .22 and .25 calibers.
Adjunctive, or secondary, methods are required to ensure death when using a penetrating captive bolt. These could include a second shot with the bolt gun, exsanguination or pithing (inserting a pithing rod through the projectile’s site of entry for the purpose of increasing brain tissue damage).
Euthanasia Dos and Don'ts
Do involve your veterinarian to create a euthanasia program, so you and your employees understand the correct way to induce a "good death" that causes no pain or distress for your animal.
Don’t leave ailing or suffering animals to die. "Calves in particular are left to die in cold or heat," says James Reynolds of Western University College of Veterinary Medicine. "That’s inhumane."
Don’t use tranquilizers or sedatives along with a secondary kill-step (adjunctive method). "These agents don’t make animals unconscious," Reynolds says. "They only make them sedated or tranquilized."
Don’t use potassium chloride and magnesium chloride as the sole method of euthanasia. These agents should be used only in unconscious animals for the purpose of ensuring death.
Don’t drag a non-ambulatory animal. "That is unacceptable," says Iowa State University’s Jan Shearer. If the animal that is to be euthanized is ambulatory and can be moved without causing distress, discomfort or pain, consider moving it to an area—before euthanization—where the carcass may be more easily reached by removal equipment.
Do recognize that euthanasia is not a procedure that all persons are mentally or emotionally able to perform. "Observation has shown that constant exposure to or participation in euthanasia procedures may result in psychological damage, leading to work-related dissatisfaction and a tendency toward carelessness or callous handling of animals," Shearer says. One way to manage this is to provide adequate training for euthanasia. Another is to change work duties to provide relief when it becomes apparent that certain duties are causing emotional distress.