Figure 2

Extrapolating between-farm association frequency from the Poultry Network Database to the Great Britain Poultry Register. County-level average probabilities of small, medium and large between-farm association frequencies, as observed in the Poultry Network Database (n = 662) (a), and as predicted following extrapolation to the Great Britain Poultry Register (GBPR) (n = 3009) using fitted statistical models (farms known to be associated with the large slaughterhouse represent only ~3% of GBPR farms and therefore cannot be seen from this figure) (b). Pie sizes are proportional to the county-level number of farms for the respective datasets.