Abortion patterns in the four models. Boxplots for the annual incidence of abortions (defined as the annual number of abortions divided by the average herd size) in herds with- and without extinction of the infection after 10 years simulation (A, C, E and G) and rolling monthly incidence of abortions (defined as the number of abortions over four weeks divided by the number of animals pregnant at start of a four week period) in herds without extinction (B, D, F and H). The red dotted line in the panels B, D, F and H indicate the 5% rolling monthly abortion incidence that was notifiable in the Netherlands during the epidemic. In the legends, the numbers in between brackets indicate the total number of herds which got rid of the infection over the 10 years of simulation, and the number of herds which did not. A, B) model with 770 goats; C, D) model with 50 goats; E, F) model with 770 cows; G, H) model with 50 cows.