Guinea pigs are valuable research animals because of the variety of experiments in which they can be used. They are often used to test lotions and ointments because their skin resembles human skin. Long use of the guinea pig in bacteriological and serological research has resulted in a sizeable accumulation of information on blood values, cell counts, elementary analyses and physical constants. Guinea pigs have been used frequently in nutritional research and in immunology experiments.
Guinea pigs became known to research scientists after sailors brought them to England from Peru as pets. The Dunkin-Hartley strain, developed by the British, is the most widely used in laboratories. It is almost always an albino with short, smooth hair. A second type of guinea pig, the Abyssinian, has short, rough hair that grows in rosettes. The present day Peruvian type of guinea pig, with long hair, is seldom used in research.
Of all of the commonly used lab animals, guinea pigs are one of the most nervous and high-strung species. The guinea pig needs to be approached quietly and confidently. It will seldom scratch a human when it is picked up if it is supported well. If it does become alarmed, however, the whole colony can detect the fright and become apprehensive. To pick up the pig, grasp behind its head and in front of its forelegs with the thumb and forefinger. With the remaining fingers, hold the pig behind its front legs and rib cage. Use the other hand to support the hindquarters.
Good sanitation is extremely important in the guinea pig colony. The animals are very susceptible to paratyphoid infections. Cages need to be cleaned often to keep the animals as free of microorganisms as possible.
Like monkeys and human beings, guinea pigs need daily doses of vitamin C to prevent the development of scurvy. Scurvy can develop within seven to ten days without dietary vitamin C. Normally a daily intake of 10 milligrams of ascorbic acid will be adequate to keep the guinea pig free from scurvy.