Figure 4

BVDV persistence in a beef cow-calf herd for heterogeneous versus homogeneous contact structure on pasture. Two scenarios of contact structure were considered (solid line: heterogeneous; dotted line: homogeneous) for three herd sizes (blue: 42 bred females; black: 83; orange: 125) and three types of initial virus introduction (top: in week 40; middle: in weeks 20, 25 and 30; bottom: in week 27).