Geography, Veterinary

the study of the influence of the geographic environment on the health and productivity of animals (primarily domestic) and the distribution of animal diseases.

Veterinary geography studies the natural territorial complexes that determine the preconditions, nature of distribution, and typical characteristics of the course of diseases in specific areas. The primary methods of veterinary geography are expeditionary studies, the generalization of statistical data, and description. Veterinary geography is based on the veterinary and geographic sciences and is closely linked to medical geography. It uses the methods and achievements of mathematics and zoology, botany, and the other natural sciences. It became a distinct discipline with the development of veterinary medicine, which relies on its achievements and discoveries.

Veterinary geography evolved in response to the need for the most extensive prevention of animal diseases, which could not be brought about without a knowledge of the pre-conditions, nature of distribution, and typical characteristics of the course of the diseases in specific areas. Some typical characteristics of the distribution of animal diseases (frequency, attachment to particular areas) were already known in ancient times. In 1846 the Russian scientist V. I. Vsevolodov was the first to point out the need for comprehensive study of specific geographic conditions in order to prevent animal diseases. Later, through the efforts of many scientists and practical workers, it was established that the appearance and geographic distribution of animal diseases are closely linked with territorial complexes. For example, fascioliasis is encountered only in areas where there are nearby bodies of water with certain mollusk species that are the intermediate hosts of the fasciole, the agent of the disease. Livestock trypanosomiases are recorded only within the boundaries of the distribution area of the tsetse fly in Africa. The distribution of piroplasmoses and parasitic diseases of animals is directly dependent on the distribution area of the ticks that are carriers of the parasites. On the other hand, populations of mollusks, tsetse flies, and ticks are possible only in those areas where the natural complexes permit these biological species to exist. The appearance of a number of metabolic diseases in agricultural animals is directly linked to the absence or poor proportion of selenium, cobalt, copper, calcium, and other elements in the soil and plants.

The development of veterinary geography became possible through the work of the Soviet scientists K. I. Skriabin (helminth geography) and E. N. Pavlovskii (natural focalization of diseases), which established the rules of the relation between natural conditions and the appearance and spread of diseases. The central problem in veterinary geography is determining the distribution areas of animal diseases (the nosoareas) and, especially, the potential nosoareas, which depend on certain territorial complexes. Geographic epizootiology also studies the distribution areas of specific infectious diseases, their historical establishment, and their current state. Regional epizootiology studies the complexes of infections and invasions that are typical of particular geographic regions. Veterinary geographic maps are very important in clarifying the laws studied by veterinary geography. Research in veterinary geography is done at veterinary scientific research institutes and at educational institutions.