Figure 4

Distribution of serum titers obtained with P48-ELISA in four distinct sheep populations: - green curve: 1195 sheep from the M. agalactiae infection-free population from the Tarn department; - red curve: 604 sheep from the M. agalactiae infection-free population from the Béarn region; - blue curve: 609 ewes that shed M. agalactiae at least one out of four successive individual milk analyses 5, 4, 3 and 1.5 months prior to blood sampling for serological testing; - black curve: 1090 animals from six infected flocks from the Pyrénées-Atlantiques department that tested positive with TA-ELISA. Titer distribution is expressed as the percentage of animals from a given population falling into each titer category. The manufacturer’s suggested cut-off point is represented by the purple broken line. The shaded area corresponds to a +/−20% confidence interval on a single measurement. The maximum titer frequencies for the Tarn and Béarn populations were respectively at 10% (97% of the population) and at 10% (57% of the population).