This experiment was conducted to study the effects of a true digestible Ca:P ratio on growth and serum characteristics (Experiment 1 ) as well as the utilization of Ca, P, N and microelements (Cu, Mg, Fe, Zn and Mn) (Experiment 2) on 20-50 kg growing pigs (Duroc×Yorkshire×Landrace). Total dietary contained 0.26% true digestible P, and the dietary true digestible Ca:P ratios were 0.89, 1.37, 1.82, 2.29 and 2.75, respectively. The basal diet was formulated containing corn, rough, soybean and rapeseed with monocalcium phosphate and limestone use...