Debate For and Against Euthanasia in the Control of Dog Populations

Dogs share the same environment of humans and play an important role in their ecological adjustment. Since its domestication 12,000 to 15,000 years ago, they have been part of human evolution with increases on its population as humans settle down. Dogs provide social and health benefits to humans but they may also be involved in social conflicts such as bites, zoonosis, destruction of ecosystems, etc. As consequence of its uncontrolled and logarithmic growth on its population, several strategies have been taken in both developed and developing countries. Under these two scenarios, euthanasia is employed as part of the strategy to overcome the surplus of this species. However, ethical issues arise when healthy dogs are killed or methods used for euthanasia are inhumane and against international standards. Besides, euthanasia as a method to control the dog overpopulation has shown to be expensive and ineffective on long term. In humans euthanasia is restricted to compassion or “mercy” killing to relief the patient of an terminal disease or when life become too painful and with poor life expectative. In veterinary medicine the term euthanasia is broader since it also includes healthy animals such as dogs, for elective euthanasia considering owner convenience, reasons of overpopulation, for behavior problems or research purposes. Canine overpopulation arises when uncontrolled breeding of dogs and irresponsible ownership act together. Dogs are promiscuous species by nature and since not a well defined seasonality occurs in this species, are ready to mate all through the year. Owners frequently claim their rights to own a dog but may be reluctant to take care of their responsibilities. If no laws to regulate dog ownership exist or if they exists but are not reinforced, the imminent consequence will be a surplus of the species ending on the streets or shelters. Even in shelters, it is estimated that 2 out of 3 animals entering a shelter won’t have a chance to be adopted and have to be euthanized. Several methods for euthanasia in dogs have been used. Some are recommended by international associations and others are considered illegal in some countries. Barbiturates (pentobarbitone or pentobarbital sodium) are by most the more common used drug for euthanasia in dogs; barbiturates cause deep anesthesia and unconsciousness before leading to respiratory failure. However, in case of anesthetized animals other methods such as Magnesium sulfate, potassium salts, carbon monoxide gas and even captive bolt shots can be administrated. Some inacceptable methods, still used in some countries are the use of