Fig. 5.

Benefit per R (BPR) simulated at the end of the grazing season (day 180) on a population basis for each of the simulated control strategies; BPR represents the benefit in empty bodyweight gain (kg) per change in frequency of R on pasture, so the higher the value the more beneficial the strategy is perceived to be. Ten discrete populations of calves were simulated on pasture initially contaminated with 200L₃/kg DM grass for calves treated strategically with ivermectin at 3, 8 and 13 weeks post-turnout or according to threshold values of average daily bodyweight gain (ADG, kg/d), faecal egg count (FEC, eggs/g), pepsinogen or a combination of FEC and pepsinogen. Statistical comparisons were made between groups and are reported within the text.