For the no-treatment group (Figure 2B), the fact that no prior washing of the eggs had occurred may explain the low correlation between the rinse and crush-and-rub APC recovery values for this group. Because these eggs were being sampled as is from the hatchery, this presents the likelihood of wide variability in the eggshell rinse numbers because of the wide differences in initial eggshell aerobic bacteria contamination, even though only nest-clean eggs were used. For Q4B, not only was the correlation the lowest, but the data points were also shifted closer to zero for both the rinse and crush-and-rub methods, as indicated in Figure 2F. For Q4B, the spread in data points ranged between 0.5 and 4.0 log10 cfu/mL for the rinse method and between −0.3 and 3.3 log10 cfu/mL for the crush-and-rub method. This was a smaller range for both the rinse and crush-and-rub methods compared with all other treatments (1.3 to 5.3 log10 cfu/mL for rinse, and 0.0 to 4.6 log10 cfu/mL for crush-and-rub). This indicates that the low correlation between the rinse and crush-and-rub methods for Q4B was the result of increased variability, which may be explained by the enhanced killing or removal of bacteria from the eggshell. As can be seen in Figure 2F, Q4B exhibited a bimodal distribution pattern. After data from each of the 4 trials were separated, this pattern was determined to be a trial effect, although none of the trials was statistically different (P > 0.05) within the Q4B treatment.