title: [Attempt to design a factorial model of Newcastle disease in poultry in Bulgaria for the period 1970-1979].
abstract: Literature data on the statistical methods relating to many objects (informational, factorial, clusteral, regressional, etc.) in the study of epizootic processes have shown that these methods could be employed to raise the quality of the epizootiologic analysis. An attempt has been made to build a factorial model for Newcastle disease in this country. Use has been made of a programme for factorial analysis, substantiated by a computer. The information is presented in the form of a matrix, containing 27 rows (the number of districts) and 15 columns (the number of indices). The latter include parameters of the epizootic processes as well as indices, characterizing the economic status of the individual districts. The factorial model has made it possible to state the correlations of a great number of measurable indices and through these to disclose 4 basic factors that cannot be measured directly which may largely contribute to the elucidation of the epizootic status. The concept has been confirmed that the character of the epizootic process with the Newcastle disease within the size of concrete territorial-and-administrative units (the districts) is determined to a great extent by the economic features of the districts. The programme used in the factorial analysis of Newcastle disease can be applied also to investigate the epizootic process with other infectious diseases of farm animals and birds along with the use of a computer and available information.
mesh_terms: D000818:Animals; D002031:Bulgaria; D003201:Computers; D004197:Disease Reservoirs / Q000662:veterinary; D005163:Factor Analysis, Statistical; D008954:Models, Biological; D009521:Newcastle Disease / Q000453:epidemiology*; D011200:Poultry; D012189:Retrospective Studies / Q000662:veterinary
vernacular_title: Opit za postroiavane na faktoren model na psevdochumata po ptitsite u nas za period 1970-1979 g.