Some veterinarians, referred to as principal investigators, participate in biomedical research by directly initiating and leading research programs at academic and corporate research institutions. Veterinarians also contribute to research programs as co-investigators, research scientists, and technical advisors. In fact, many of the first discoveries in modern biomedical research originated from veterinarians investigating diseases common to both humans and animals, such as blood-borne parasitic diseases and leukemia. These discoveries have led to major advancements in the understanding and treatment of human and animal diseases, and have occurred in every major field of biomedical research.
In 1898, the veterinarians Loeffler and Frosch were the first to discover an animal virus when they demonstrated that a particle smaller than a bacterium could cause foot-and-mouth disease (Brown, 2003). Ten years later Danish veterinarians Ellerman and Bang (1908) provided the first evidence that some leukemias are caused by viruses. William Hadlow, a Public Health Service veterinarian, discovered histologic similarities between scrapie and kuru, leading to the breakthrough research on prion disease (Eklund and Hadlow, 1973). Smith and Kilborne (a veterinarian) (1893) were the first to demonstrate that an insect could transmit disease. Their research into identifying the arthropod vector for Texas fever contributed to the discovery that mosquitoes transmitted malaria and yellow fever. Veterinary medical scientists continued to make significant contributions in microbiology, especially in the field of retrovirology where the feline retroviruses were investigated by William and Oswald Jarrett, Neils Pedersen, Charles Rickard, Max Essex, William Hardy, and Edward Hoover; chicken retroviruses by Peter Biggs; and cattle leukemia viruses by Carl Olson, Martin van Der Maartin, and Arsene Burny, all veterinarians (Gallo, 1991). Theilen, Essex, and many other veterinarians were among the first to study simian immunodeficiency. This important animal model continues to advance our knowledge of human acquired immunodeficiency syndrome through studies led by the veterinary scientist A. A. Lackner and associates, among others (Veazey and Lackner, 1998).
Veterinarians have been instrumental in elucidating the etiopathogenesis of many infectious (NRC, 1991) and non-infectious (Fox et al., 2001) diseases of laboratory animals, and they continue to make important contributions, such as the recent discovery of murine Helicobacter spp. and their role in disease (Fox et al., 2000). Others have contributed by defining the pathologic and clinical chemical changes seen in infectious and non-infectious diseases of laboratory animals (Percy and Barthold, 2001).