Animal Health - Treatment & Needs - Dogs

What has animal experimentation achieved so far?

Spectacular improvements in the welfare of dogs have been achieved as a result of work to develop vaccines against common viral and bacterial diseases. It is now possible to prevent our pets being affected by diseases that were often fatal (notably distemper, parvovirus and infectious hepatitis) or severely affected the animal’s quality of life (such as the respiratory disease kennel cough).

Pets are now living longer, healthier lives [Corbis].

What diseases are important now?

As vets have acquired the power to treat most of the infectious diseases that affect dogs, more pets are living to a ripe old age. They then start to suffer the same sort of degenerative diseases that affect elderly humans – cancer, heart disease, arthritis, etc. Much of the relatively small annual budget available for pet animal research in the UK is directed at new treatments for these ailments. Some dogs will eventually receive treatment with drugs produced by human pharmaceutical company but any new treatment will need careful testing in dogs – paracetamol relieves pain and fevers for humans, but readily kills cats.

Veterinary scientists also have to be on the look out for new diseases. In 2000, it was decided to end the system of quarantine for dogs entering Britain from Europe. New controls were introduced that gave equal protection against the threat of rabies. But the new system has increased the risk of introducing exotic parasitic diseases such as leishmaniasis and ehrlichiosis, which are also potential threats to human health.

Meanwhile, dogs are likely to benefit from the revolutionary techniques being developed in genetics. Among the 400 or so different breeds of pedigree dogs in the world, almost every one suffers from one or more genetic disorders. Last year, US scientists announced that they had completed the first map of the dog genome. This should greatly accelerate the process by which scientists can locate the defective genes responsible for hereditary disease. Once the source of the problem has been found, it is then possible to start looking for a cure or to develop tests to allow the defective gene to be bred out of the population.

How can humans benefit from research on dogs?

More than 100 genetic diseases identified in dogs are virtually identical to conditions that occur in people. Previously, the genes responsible for genetic diseases in dogs were located only after finding the equivalent defect in humans. But for the first time recently, US scientists were able to find the source of a human disease after locating the gene responsible for a similar condition in dogs. This was a disease called narcolepsy in Dobermans, in which dogs suddenly fall asleep when excited or during exercise.

Basic research on dogs affected by one of these genetic conditions can help understanding of the disease mechanisms that occur in both human and canine patients. Dogs can also be used in early stage testing of any new treatments for these conditions, when it would be inappropriate to risk trying them in people. Dogs are also useful models for understanding many human diseases in which genetics plays either a minor role or none at all, such as pancreatitis, diabetes and some forms of heart disease.