The final population density (N) of species of mites on antibiotic additive diets and fitted concentration EC50 is an effective concentration of antibiotic s in diets for 50% population growth reduction in the comparison to growth on control diet.

Legend: The final population density is expressed as mean ± standard deviation; the polynomial regression (r = ax2+bx+c; x = antibiotic concentration mgg−1 of diet) describing the suppressive effect of antibiotics to growth rate of tested mites. The antibiotic concentration was transformed logarithmically (LN concentration +1×10−7). The fitted parameters are showed with 95% confidence limits in parenthesis.The final population density (N) of species of mites on antibiotic additive diets and fitted concentration EC50 is an effective concentration of antibiotic s in diets for 50% population growth reduction in the comparison to growth on control diet.