Selected Topics in Animal Welfare

The term "euthanasia" means "good death." The American Veterinary Medical Association (AVMA) publishes guidelines for the euthanasia of animals, which detail the methods and agents appropriate for different species (see also Euthanasia in Animals). Veterinarians should consider not only the method and the agent but also the handling technique and postprocedure disposal of the body. Other factors, such as human safety, might dictate the practicality of implementing a particular method of euthanasia. The chosen method should be rapid and minimize fear and distress for the animal. The timeliness of euthanasia also has an impact on animal welfare; for example, if an owner elects to keep a pet alive without providing appropriate relief from pain and suffering, the welfare of the animal is compromised (1).

Slaughter is the killing of an animal for human consumption. Methods for stunning an animal (rendering it unconscious) before it is killed vary by species, and stunning usually precedes exsanguination, except in the case of religious slaughter, for which there are exemptions.

Depopulation is killing large numbers of animals in response to a public or animal health emergency. The AVMA publishes guidelines for the depopulation of animals.

Free-ranging and feral animals are either domesticated and escaped from their environment or descended from owned animals and sometimes considered "wild." The welfare of a free-ranging or feral population is balanced against the welfare of other animals affected by their presence.

Feral cats and free-roaming horses are at the forefront of debate. Feral cats are estimated to kill millions of songbirds annually in the US, along with up to 22 billion small mammals (2). Feral horses in the US compete with each other and native wildlife for limited resources on federal lands, primarily in western states. Feral horses are captured and are either neutered and returned to the wild, adopted, or kept in long-term holding facilities.

Many animals are used for entertainment purposes, in rodeos, roadside zoos, circuses, and the like. The use of these animals for these purposes raises several questions regarding animal welfare.

The welfare of rodeo animals is affected by intense physical exertion during such events as calf-roping, barrel racing, andcutting (separating a single cow from a herd). A horse or bull might be subjected to physical manipulation by a flank strap (a leather band strapped around the abdomen to create an aversive sensation that causes the animal to buck). Calf-roping and steer tripping (roping a running steer by the horns, causing it to flip over) can lead to injuries. Charreadas are Mexican rodeos that include even more dangerous events, such as horse tripping and steer tailing (grabbing the tail of a steer and wrapping it around the animal's leg or a stirrup in order to drag the animal to the ground).

Handling of wild animals by humans during interactions at roadside zoos, traveling animal shows, and similar venues can cause great stress in these animals and can potentially result in the transmission of zoonotic diseases. These facilities, although regulated by the USDA, are not typically overseen by the Association of Zoos and Aquariums; therefore, the risk for inappropriate handling and poor husbandry is high.

Animal use in circuses has come under greater scrutiny for inhumane practices, resulting in some, but not all, circuses eliminating elephants from their shows. Large cats and other animals remain, and the husbandry and training techniques used with these animals are sometimes questionable.

In the US, cities, counties, states, and the federal government have various regulations outlawing animal abuse. Veterinarians in some states are mandated reporters for animal abuse; even if they are not mandated, veterinarians have a responsibility to help protect animals, in accordance with the AVMA veterinary oath.

Human-organized animal fighting, including dogfighting and cockfighting, is illegal in the US due to concerns over animal welfare, yet it remains popular in some areas. Animals used for fighting are kept in poor conditions and are sometimes given illegal drugs to enhance their fighting ability. Fighting cocks are outfitted with metal spurs or knives to injure the other bird. Animals often fight to the death.

Neglect is defined as the persistent failure to meet an animal's fundamental physical and psychological needs. Unlike abuse, which involves deliberate acts of commission, neglect is primarily an omission of care. It exists on a broad spectrum, ranging from husbandry deficiencies to life-threatening deprivation. Examples include the following:

• not providing adequate nutrition (improper feeding or starvation)

• not providing an appropriate environment (outside of thermoneutral zone, inadequate bedding or sanitation)

• not providing opportunities to express positive behaviors (social isolation or crowding, extended confinement)

Failure to provide appropriate medical and veterinary care, via prevention or treatment, can also constitute neglect. If an owner declines prevention or treatment, or is financially unable to provide an animal with proper nutrition and care, education and communication should be offered. However, the responsibility remains with the owner to provide basic care for adequate welfare.

It can be challenging to identify cases of neglect. A thorough patient history and physical examination are imperative. Some physical findings of neglect include the following:

• emaciation

• poor or matted hair

• dehydration

• unexpected behaviors (eg, fear, avoidance)

Laboratory testing might reveal underlying pathologies that explain these findings, or the findings might be the result of neglect. Very low albumin concentration can be a good indicator of prolonged starvation. CK activity might also be elevated as a result of increased muscle catabolism. The presence of infectious diseases, external parasite infestations, scars, or diseases chronic in nature can also be indicators neglect.

As with abuse, veterinarians are mandated in many US states to report neglect. Even in states where veterinarians are not mandated reporters, they should communicate with authorities in order to promote good animal welfare, in accordance with their veterinary oath.

• Guidelines for the euthanasia of animals. American Veterinary Medical Association.

• Guidelines for the depopulation of animals. American Veterinary Medical Association.

• Animal Care. Animal and Plant Health Inspection Service, USDA.

• Also see pet owner content regarding welfare of pets and euthanasia and pet loss.

1. Knesl O, Hart BL, Fine AH, et al. Veterinarians and humane endings: when is it the right time to euthanize a companion animal? Front Vet Sci. 2017;4:45. doi:10.3389/fvets.2017.00045

2. Loss SR, Will T, Marra PP. The impact of free-ranging domestic cats on wildlife of the United States. Nat Commun. 2013;4:1396. doi:10.1038/ncomms2380