[Fertility problems caused by infectious agents pigs in the Netherlands(author's transl)]

The concept of fertility problems is defined in the introduction and their economic importance in pig breeding are pointed out. The infectious causes of the problem are reviewed. Infections with L. tarassovi and with Aujezky's virus regularly lead to practically endemic abortions; Brucella suis and swine-plague infections do so sporadically. The SMEDI syndrom is considered. The clinical symptoms, diagnosis, epizootiology, and the therapeutical and prophylactic measures of these infections are discussed. In the case of brucellosis, attention is paid to the differential diagnosis in the serological examination. The incidence of Yersinia enterocolitica among the Dutch pig population is high. This micro-organism has antigen components in common with brucellae. In Holland the significance of infectious agents as the causes of sterility is not considered to be high.