Comparison of intermittent and continuous shedding. A. Upper left panel. Histogram of positive sample number (full black line) and total number of samples (grey line). The ratio between the two is not constant showing that positive samples are not a simple artefact of the analysis with a constant probability. B,D. Upper right and lower right drawings fraction of cows not reaching high shedding and cumulative hazard of reaching high shedding for intermittent cows and continuous cows. The hazard to become a high shedder is significantly lower in intermittent cows than in continuous cows. C. Lower left panel Histogram of time from birth to high shedding for intermittent and continuous shedders. The distribution is highly similar among the two groups.