Terminology
Enzootic (= endemic) disease - This means that the disease, or at least the infection causing it, is permanently present in a population. In relation to diseases of pigs the population may be a herd or the herds in a region, a country or a continent. Strictly speaking 'endemic' should only be applied to populations of people (demos meaning people e.g. democracy) and 'enzootic' should be used for animals but in practice the two are interchangeable.
Epizootic (= epidemic) disease. - A disease which spreads, usually fairly quickly, to a large proportion of the pig population. The term 'endemic' is often used instead but strictly speaking "endemic' applies to people not animals.
Erosion - A shallow ulcer.
Exotic disease - A disease which does not occur in the region or country of your pig farm.
Pandemic disease - A disease which is widespread throughout a region or the world.
Ulcer - A localised inflamed surface or gut lesion from which the skin or surface membrane has been removed by trauma, chemicals or infection.
Vesicle - A blister containing clear or yellow-tinged liquid under the superficial layers of the skin or surface membrane of the mouth or gut.
Vesicular diseases - Viral diseases in which vesicles are a prominent feature. The vesicular diseases of pigs are foot-and -mouth disease (FMD), swine vesicular disease (SVD), vesicular exanthema of swine (VES) and vesicular stomatitis (VS)