Figure 4.

The relationship between liver abscess A+ (score 3) incidence (LAI A+, %) vs. ADG (kg/d) and virginiamycin dosage (mg/kg DM). The large blue dots (≥100 animals) and the small red dots (<100 animals) are observed data points, combined across studies (n = 57). (A) Binomial logistic (logit function) regression, including 53 individual data points: $LAI A+=100\times Exp[-1.196-0.0286\times dose-0.128\times ADG$ The coefficient for ADG was not different from zero (P > 0.43). (B) Binomial logistic (logit function) broken-line regression, including 53 individual data points: $LAI A+=100\times Exp(-8.98-0.0191\times \left\{dose<12.34,dose,12.34\right\}-0.0433\times \left\{dose<12.34,0,dose-12.34\right\}+5.89\times \left\{ADG<1.42,ADG,1.42\right\}- 3.286\times \{ADG<1.42,0,ADG-1.42\})$. The first slope for dose was not different from zero (P > 0.05). The breakpoints were 12.34 ± 9.79 mg/kg of DM for virginiamycin and 1.42 ± 0.019 kg/d for ADG.