© istockphoto/Ina Peters
Cats share many cellular functions with humans. They have been domesticated for centuries, and have been used in scientific research from the early days of medicine. Since 1898, cats have contributed to the study of emotion, cardiac disease, spinal cord injury, cataract surgery, glaucoma, lupus, diabetes, spina bifida and more. These diseases are common to both humans and cats, and research in these areas has helped our understanding of human disease and the advancement of veterinary research.
Cats are mainly used as models to study sensory systems and neuroscience. They have acute hearing, excellent eye-sight and highly developed balance and spatial awareness. These highly developed senses have always interested scientists, and more is known about the anatomy of the cat's sensory systems than those of any other animal. Cats also have well developed cognitive abilities and memories, and have often been used in laboratory tests of learning ability, with results which have been applied to human educational practices.
As reliable anaesthetic methods and delicate instruments to examine the nervous system have been developed, cats have been used to study a variety of neurological problems, such as epilepsy, deafness, and vision problems, making great contributions to our understanding of the nervous system.
The visual system
David Hubel studied the development and function of the visual system in cats, finding that all mammals, including humans, are born with a partially-developed visual system. He built on information from previous detailed studies of the nervous systems of kittens,1 and found that proper development of the eyes, optic nerve and visual centres of the brain requires stimulation of the visual neurons by light. This work was awarded the Nobel Prize in medicine in 1981.2
The relatively long life span of cats, compared with mice and rats, makes it possible to observe the slower and more subtle effects of aging. Cats are known to reach the age of 16-20 years, and advances in treating many feline diseases have extended their life-expectancy.
Leukaemia, a malignant disease of the blood-forming organs, resulting in the uncontrolled production of abnormal white-blood-cells, is perhaps the most infamous of the diseases shared by cats and people. In cats, a condition similar to leukaemia in humans is caused by a retrovirus which was discovered in 1965. A vaccine for the feline leukaemia virus is available and has been refined over the years. Mammary cancer is also common in the cat, and many features of feline mammary cancer resemble human breast cancer which, among the human cancers, is the greatest killer of women.
For many years vets treated cats with symptoms of feline leukeamia, where they were unable to isolate the virus. In 1986 researchers found that this disease was caused by a different retrovirus, which was similar to the HIV virus in humans. The retrovirus became known as feline AIDS (T-lymphotropic lenti virus),3 and is thought to be transmitted through bite wounds, although the virus can remain dormant for years before causing disease, so there may be other routes of infection. FIV is not transmissible to humans, but the virus is genetically similar to HIV, and diseases caused by the virus are very similar. Cats which are naturally infected with the FIV virus are used as models to study effective anti-viral treatments for AIDS, which will benefit both cats and humans. The recent development of an FIV vaccine has given a potential new model for use in HIV vaccine development.
Detailed information about the FTLV assay and the disease can be found at Patents online.
Related link: Feline T-lymphotropic lentivirus assay patent information
1. Lorente de Nó, R. (1949) Cerebral cortex: architecture, intracortical connections, motor projections. Chapt. 15 in Fulton. J. F.: Physiology of the Nervous System. 3rd edition, Oxford University Press, New York and London
2. Hubel, D (1981) Nobel lecture. http://nobelprize.org/nobel_prizes/medicine/laureates/1981/hubel-lecture.pdf