Fig. 3

Fitted linear broken-line plots of the average concentration of bone ash (g) as a function of phytase inclusion level. The optimum concentration of phytase determined by linear broken-line model was 1,222 (SE = 378.1) units of microbial phytase (FTU)/kg of feed; [Y = 3.20 − 0.001 × (1,222 − X)] where X is less than 1,222, with r² = 0.914 and P < 0.05. The SE for the estimates of the intercept and second parameter were 0.123 and 0.0004, respectively