Fig. 1

Schematic view of egg-release by SWB model population strata. Each host in h _k -stratum (k = 0, 1, 2, … ) carries, on average, ϕ _k mated worm couples, having fecundity factor ρ _k . However, because egg-release/worm is random (in a negative binomial pattern with aggregation r _k  = r ϕ _k ), test results for the h _k -stratum can actually be distributed over a broad range of egg-counts {d _m }