[Changed health problems in a changing pig-farming concern in The Netherlands until 1980]

In 1905 Poels published 'Disease of swine in the Netherlands'. This book dealt predominantly with swine fever, erysipelas, tuberculosis and 'pneumonia'. Between 1920 and 1940 others reported on streptococci, lobular haemmorrhagic pneumonia, bordetellosis, Aujeszky's disease and postweaning diarrhoea. After the second world war, particularly after 1960, the Dutch pig-farming industry developed at a tremendous rate. As a consequence, the health problems changed. Certain diseases became less important: tuberculosis, erysipelas, Leptospira tarrasovi, enteroviruses. Yet other diseases including postweaning diarrhoea, atrophic rhinitis and Aujeszky's disease became problems of increasing importance. At the end of the seventies the knowledge of E. coli toxin types was substantial. On the other hand, information concerning the pathogenesis and pathophysiology was very limited. Bordetella bronchiseptica was still considered to be the most important agent in AR, zootechnical factors being predisposing. However, one was aware of missing links. Aujeszky's disease was obscure until the late fifties. Until 1972 only occasional reports were made. In that year, an epidemic occurred in the Gelderse Vallei. Another epidemic occurred in 1974 in the provinces of Brabant and Limburg. By 1980 proper vaccines were available and Aujeszky's disease was not yet a political problem.