Guinea Pigs as Experimental Models

The guinea pig, like many animals used in biomedical research today, first became popular to enthusiasts and fanciers. This popularity fostered familiarity with its behavior, physiology, and suitable husbandry conditions, and this knowledge about care and husbandry subsequently allowed successful transition into laboratory housing, making it a popular research model. The guinea pig first served as a useful animal model of disease and was used in the study of respiratory physiology. Guinea pigs were further used in studies of infectious disease, and seminal work on the role of certain vitamins in maintaining health. Through time it was learned that, beyond the virtues of its relatively small size and docile nature, the guinea pig possesses anatomical and physiological features that make it uniquely suited to certain studies. For example, guinea pigs are useful in reproductive studies because they and humans share similarities in placental structure, their gestation period of 68 days can be divided effectively into trimesters akin to the human condition, and they can develop pregnancy toxemia. The most commonly used variety is the Hartley albino stock, but the inbred strains 2 and 13, and euthymic hairless stock are also used with some frequency. A principal reason for the overall decline in use is the increased use of mice as a favored animal model. The paucity of inbred guinea pig strains and the limited number of specific reagents for use with the species are two factors that generally limit the use of this species in research in the foreseeable future.