Robert C. Dysko, et. al., "The Biology and Diseases of Dogs," Chapter 11 in Laboratory Animal Medicine, 2nd Edition, James G. Fox, et. al., editors (New York: Academic Press, 2002)
Laboratory Animal Management: Dogs (online book from National Academy Press, 1994)
Chapter 28 in The UFAW Handbook on the Care and Management of Laboratory Animals, 7th Edition, Volume 1, Trevor Poole Editor, Pauline English Editorial Assistant (Malden: Blackwell Science, Inc., 1999)
Dogs are descended from a tree climbing carnivore that appeared some 40,000,000 years ago; 7,000,000 years ago the Canidae family began to differentiate into wolves, foxes, coyotes, fennecs and jackals. It has long been assumed that dogs were first domesticated in Europe and Asia around 10,000 years ago; they followed nomadic groups eating leftovers and gradually became used as watchdogs and protectors. Recent studies of fossil records, however (see Stalking the Ancient Dog), have generated the hypothesis that domestication occurred much earlier.
Whenever the domestication did occur, ensuing selective breeding of the four main groups descended from that original ancestor—herd dogs, hounds and terriers, Northern and toy dogs and guard dogs—resulted in over 400 separate breeds. There continues to be conservation efforts focused on the entire canine family, e.g. see the Canid Specialist Group. Suffice it to say that dogs are an ancient species with a long history of living with human beings. Because of their socialization with human beings they are used as therapy aids for particular populations of patients (see Psychiatric Dogs) and as Police Dogs.
Their innate characteristics, e.g. their pack social structure and hunting life style, as well as the long tradition of domestication, are indications for their care in a research setting. Although different breeds vary in requirements, all dogs need regular exercise and social interaction with other dogs and are extremely responsive to training and handling. The regulations concerning dogs state that unless there is scientific justification otherwise, they must be provided opportunity for exercise. Details are left up to the individual research teams. Since dogs are pack animals, every attempt is usually made to pair or group house them; if they need to be singly housed they should have daily access to each other, when compatible, in some fashion. Many research institutions provide some sort of indoor group housing with access to larger run areas. Dogs and Dog Housing, a publication of the Animal Welfare Information Center, is a good summary of some of the current thinking about the housing and social needs of dogs as is Comfortable Quarters for Dogs in Research Institutions
Most of the dogs used in research are beagles due to their convenient size and docile nature. Larger dogs, such as Labradors are often used for orthopedic research. Just as mice and rats are unique in being highly genetically selected for research needs, pigs unique in their use as a food source, dogs are a special sort of laboratory animal in that they have been companion animals for many centuries. Because of this emotional tie that many feel toward dogs, their use in research has been an area of public concern.
Research workers, especially the technicians and handlers who take care of the dogs on a daily basis, often also have strong responses to their dogs and become emotionally involved with them. As a result of this bond between dog and people, there are many research programs that offer their research dogs for adoption after the study is over. (For example, see Housebreak Hotel from Texas A&M College of Veterinary Medicine). Although euthanasia of any animal causes stress, the bereavement experienced by those using dogs needs special recognition.
Euthanasia of dogs or any other animals can be stressful for the personnel performing the procedure. The degree of distress experienced by people observing or performing euthanasia depends on their backgrounds, personal philosophies, and ethical views on the use of animals in research. (Arluke, 1988) People often transfer to the death of animals their unpleasant reactions to human deaths, and their responses to euthanasia can be magnified when strong bonds exist between them and the dogs being killed (e.g. strong bonds often develop between animal-care personnel and seriously ill canine models that require a great deal of care and rely totally on their human guardians). The stress experienced can be manifested as absenteeism, belligerence, careless and callous handling of animals, and high turnover rate. To be responsive to those concerns, institutional officials and supervisors should be aware of and sensitive to the issues and should provide opportunities for individual and group discussion and support and for educational programs that furnish factual information about euthanasia and teach stress-management and coping skills. (NRC, 1991) (Veterinary Care, in Dogs: Laboratory Animal Management)
Dogs and science
Because of their history of domestication and tractability dogs have a long history as research subjects. Early studies on blood circulation and drug administration used dogs. Their use in diabetes research has been well documented. The Jackson Lab, in the early years, conducted well known genetics research using dogs. They have also been used, along with non-human primates for maternal deprivation studies. The Animal Welfare Information Center maintains a number of databases and bibliographies; “Housing, Husbandry and Welfare of the Dog” contains article references to a wide range of topics.
In modern times, beagles have become the breed of choice, due to their useful size and docile temperament. Due to their genetic heritage as pack animals they need early socialization and interactions with people while working as lab animals:
To prepare dogs for their work in a laboratory environment, they need to be able to socialize with their own species and with people. Laboratory dogs need to be able to adapt to change as they may move between different establishments and encounter a wide variety of challenging environments and interactions. Dogs need to be trained and habituated to specific procedural work and trained to differentiate between work and play. The most important developmental phase in relation to canine social and emotional development is the socialization period, which is believed to run from 4-14 weeks of age. Manipulations made during this time have the most pronounced effect on future welfare…(Preparing Laboratory Beagles for Life as Working Dogs)
There are three categories of research dog—purpose bred, random source and conditioned. Purpose-bred dogs are bred specifically for research and obtained from Class A dealers who raise all their dogs in a closed colony on their own premises. Random-source dogs are gotten either directly from shelters or from Class B dealers: these dealers purchase the dogs either from individuals or shelters and then sell them to research labs. Once random-source dogs have been quarantined, vaccinated, and determined free of parasites and any other medical or biological anomaly, they are considered “conditioned.” Every institution will have specific regulations for the receiving and processing of dogs, whatever their category. As an example, see the University of Michigan’s Laboratory Animal Medicine standard operating procedures.
Historically dogs have been used for surgical research and practice and for drug testing, both basic pharmacological trials and toxicity testing. Another major area is in researching canine familial disorders that are analogous for similar human diseases. There is also a great deal of research about dogs themselves, for example, the Canine Olfactory Detection Laboratory at the Auburn University College of Veterinary Medicine.
The Canine Olfactory Detection Laboratory was established in 1989 to conduct research and development (R&D) efforts that support a variety interests and challenges associated with canine detection technology. The basic design of the Olfactory Lab gives us the ability to assess and quantify the olfactory capabilities of dogs using the principles of behavior analysis, a specialty field within experimental psychology.
The bonds that form between dogs and people have lead to public concerns over their use as research subjects; in particular, the argument over the use of stray or abandoned dogs, "ex-pets," has been a source of contention. In 1966, Life Magazine published an article titled “Concentration Camp for Dogs,” an expose of the practice of selling dogs, either those purchased from shelters or found abandoned, to research institutions. The resulting public outcry led to the Animal Welfare Act of 1966 legislation that has since been enlarged upon and ammended several times. This case also spearheaded efforts to establish The Animal Welfare Institute, an organization that strives for a middle ground, a liaison between the public and the laboratory animal research community. The discussion over the use of shelter or stray dogs as research subjects continues today, with some states permitting and others forbidding shelters to sell dogs to dealers.
The argument over whether or not to use stray/abandoned dogs for research is part of the larger issue of animals in society, and the range of attitudes towards them. Shelters point out the dilemma they face over confronting owner neglect, questioning whether a dog disappearing can be, in reality, tied to dealer activity. The care and housing of greyhound dogs used in racing points out another example of the spectrum, with people viewing a greyhound as either a commondity, a financial tool, or a househould companion. Proponents of using retired greyhounds as research subjects, note that these dogs have known genetic records, have a defined health status and vaccination history, and are well used to living in caged quarters. And, unlike pet dogs, when their usefullness is over, they are euthanized.
Online resources for education and training in working with dogs
The National Research Council’s Laboratory Animal Management: Dogs contains much userful information. This book is available online via the National Academies Press. Chapters include materials on selecting experimental animals, husbandry, general veterinary care and specific care for animal models. Another resource for training in the care and use of dogs is the Office of Laboratory Animal Welfare’s (OLAW) online video:
"Working with the Laboratory Dog" helps meet the training mandates for research staff using dogs in biomedical research. This video presents basic techniques and background information that are appropriate for all who work with laboratory dogs in a research setting. "Working with the Laboratory Dog" was produced by the Department of Veterans Affairs (VA) in 2000 with funding support by a charitable organization and with the cooperation of the American Association for Laboratory Animal Science (AALAS).
Biology and Husbandry
Dogs are carnivores with monogastric digestive systems; they are usually maintained on a commercial balanced formula with sufficient polyunsaturated fatty acid content. They need to be fed at least one meal a day; ad lib feeding can result in weight gain—a tendency in beagles—but if fed one or two meals a day, provision must be made to insure that low ranking individuals have access to food. Fresh water must always be available, either in bowls or via an automated system. The caretaker must be the dominant “member of the pack” so as to facilitate handling and cleaning. As noted, dogs at the lower end of the pack order need to be provided with assured sleeping areas and privacy places. If given free access to an outdoor run, dogs will keep their bedding area free of urine and feces; sawdust or wood chips help keep their coats clean and add to their comfort. Some sort of raised plastic bed will help conserve body heat. A new website from New South Wales has posted a 25 page Adobe document entitled Guidelines for the Care and Housing of Dogs in Scientific Institutions. Although the regulations cited are for New South Wales, the guidelines and discussions, valuable for anyone working with dogs, range from descriptions of housing design and construction, record keeping and health monitoring to culling and euthanasia.
Since dogs are a sociable, intelligent species they do best when housed either in pairs or small compatible groups in an environment affording some level of complexity and choice. There is a range of possibilities with housing dogs; one situation is a combination of indoor and outdoor pen areas, with open access to the outside run, and either wood chips or straw in the indoor area, with raised sleeping areas and privacy spaces to accommodate lower ranking individuals and another might be an indoor environment with some sort of complexity built into it. Daily contact with caretakers is important as well. It is important to provide food and water in such a way as to assure these lower ranking dogs access. The Scientists’ Center for Animal Welfare has posted the proceedings of a conference held in 1989 entitled, Canine Research Environment. This 80 page document includes articles on exercise requirements, regulations and includes research papers discussing biological responses to environment and exercise.
Temperature, humidity, ventilation and lighting
An indoor temperature range of 15-24oC, and humidity of 55 percent ± 10 percent, with 8-12 air changes per hour is suitable. New-born puppies require an ambient temperature of 26-28oC for at least the first 10 days of life. Lighting should be adequate for staff to work, and there may be a case for a low level of nocturnal illumination in totally enclosed facilities. (Robert Hubrecht, “Dogs and Dog Housing”)
Inspect all the dogs on a daily basis and in this way, something out of the ordinary will be immediately apparent. It is also a good idea to visually examine each dog in a systematic way, beginning with the general appearance and behavior. Individuals should be alert and responsive and walk without evidence of stiffness or lameness. Check that the food and water levels are at usual levels; if ad lib feeding, note either too much left over or if never any left over (overfeeding can lead to obesity); generate a normal so as to be able to note a change. The gums should be pink, not inflamed, moist and smooth, with no mouth odor. The eyes should be bright, clear, free of any discharge and responsive. Ears should be clean, without discharge or odor. Note if there is any scratching at the ears which could indicate an infection. The coat should be clean, shiny and free of parasites – note any excessive scratching. Respiration, even after exercise should be easy, without coughing. Check that urine and feces are free of blood or pus, in the amounts and of consistency and appearance that is normal for that animal.
Dogs that are purpose-bred should arrive at your facility already vaccinated and from disease-free colonies; it is helpful to obtain the animals from the same dealer so as to take advantage of group immunities. If you have bred the dogs at your facility their health status will also be known to you. There are class B dealers who do provide healthy, pre-conditioned dogs. If the dogs are from public shelters, they will need to mostly likely go into a careful quarantine protocol before considered part of the experimental population. This conditioning period is vital to protect other lab animals as well as research workers from the zoonotic diseases that dogs are susceptible to. It also serves to acclimate the new arrivals to their new situtation, become familiar with the routines and staff, form compatible relationships with cage mates, and become tested and vaccinated.
Closed colony populations are easier to keep disease free; risk can come from the occasional new dog or from handlers who own dogs at home. If the population fluctuates due to short term studies, special care must be taken to keep new arrivals separate; groups from the same source should be housed together. In some cases, the diseases can be subclinical but this can still affect research results in terms of blood values, immune suppression, healing times, etc.
Infectious canine hepatitis (fever, anorexia, malaise, leucopenia; following recovery, virus is shed in urine for several months)
Distempter (fever, anorexia, diarrhea, discharge from nose and eyes; can have nervous system sequella after disease)
Parvovirus (vomiting, diarrhea-dystentary, severe dehydration, depression, puppies or dogs in poor condition often die)
Herpes virus (infertility, abortions, stillbirths, neonatal problems)
Rabies(symptoms of mood alteration appear when virus in brain; hence the 10 day waiting period as this is the end stage of the disease.)
Canine Infectious Tracheobronchitis (Kennel Cough Complex) (appears in both mild and severe forms—mild: acute onset of dry cough, often worse with excitement or exercise, usually resolves in 7-14 days even if untreated; severe illness usually in dogs in poor condition, immunosupression or no vaccination history. In this case—fever, anorexia, depression, productive cough and mucopurulent naso-ocular discharge—treatment is needed. Highly infectious, airborne disease that occurs when dogs from mixed sources are mixed.)
Leptospira canicola (chronic or acute renal failure)
Leptospira icterohaemorrhagiae (jaundice, depression, death; this disease is transmitted via rats)
Brucella canis (abortion; orchitis in males)
Round, hook and tape worms, Toxocariasis (Diarrhea, unthriftiness—can be a severe problem in unhealthy puppies)
Mange (mites, can be carried on rodents, pruritis, infestation in ear canal causes intense itching; screen new arrivals carefully)
Ringworm (fungal disease that can spread to man, broken hair and areas of hair loss, isolate the dog and disinfect the quarters)
Fleas (worse in hot, damp climates; if dogs have access to outdoor pens/runs be sure to treat area as well as dog; thoroughly clean pens, beds)
Handling and Procedures
The University of Minnesota’s excellent Research Animal Resources website has information and diagrams on Restraint and Handling of Dogs. The University of Iowa has posted information about Anesthesia and Analgesia of Dogs. A website from New South Wales has a 30 page pdf document entitled Removal of Blood from Laboratory Mammals and Birds containing detailed descriptions of all aspects of blood collection. Another document contains details about administration of substances to animals: A Good Practice Guide to the Administration of Substances and Removal of Blood, Including Routes and Volumes.
Current research using dogs
There are a number of major genetic diseases that are homologous in the dog and man; the Fred Hutchinson Cancer Research Center’s (FHCRC) Dog Genome Project is mapping the canine genome, continuing the development of the dog as a model. Molecular biology research is now focusing on inter-species genetics research; you can see this in one project at the FHCRC, alignment of canine, human and mouse amino acid sequences.
The National Academies Press book, Laboratory Animal Medicine: Dogs, has an entire chapter, Special Considerations, devoted to the special veterinary needs of dogs who by virtue of their natural genome or induced, are used as canine models of chronic disease. Specific advice for cardiovascular, Ehlers-Danlos Syndrome, endocrinologic, hematologic, immunologic, neurologic and orthopedic syndromes are described.
1. Look over two different online postings, one from the Animal Welfare Institute (a private organization), Comfortable Quarters for Dogs in Research Institutions, and one from the Animal Welfare Information Center (a government organization), Dogs and Dog Housing. What, if any, are their points of agreement and disagreement? What seems to you to be an optimal plan for housing dogs in research institutions?
2. The argument over using random source dogs as opposed to those from established vendors is still a matter of debate. Reading through the chapter Use of Pound Animals from the National Academies Press' Use of Laboratory Animals in Biomedical and Behavioral Research, The Case Against Random Source Dog and Cat Dealers, from the Animal Welfare Institute, as well as the Ban Pound Seizure site from the American Anti-Vivisection Society, either support or defend the use of random source animals, from both a scientific and an ethical point of view. Can you separate out the scientific concerns and the moral concerns from each other, or not? Which population do you think we should use for research--—only purpose-bred, or should we include dogs from random sources? Should retired greyhounds be included? Support your positions from the readings in this site. A further resource on this question is "Where Should Research Scientists Get Their Dogs," in The Human Use of Animals: Case Studies in Ethical Choice, F. Barbara Orlans, et. al (New York: Oxford University Press, 1998).
After reading From the Leash to the Laboratory, an online article criticizing the research establishment for their involvement in random source dog sales, how would you decide the facts of the case as presented by the author? What are the perimeters of responsibilty for the USDA and/or APHIS for the movement of dogs between owners, dealers, shelters and research institutions? Although the actual researchers who end up using the dogs may be compassionate and treat the dogs well, is it possible to control the system itself when it may make use of unscrupulous individuals who are attempting to earn the most money possible from their “stock?” Do you think research scientists should have responsibility for this situation? Why or why not?