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Two experiments were conducted to in-vestigate the effects of net energy(NE)level on the performance and carcass traits of finishing pigs fed low crude protein(CP)diets supplemented with crystalline amino acids(CAA). A total of 216(Exp. 1)and 360 (Exp. 2)barrows(Yorkshire × Landrace × Duroc)were allotted to one of six treatments(n=6). The ex-perimental diets were based on corn and soybean meal,and consisted of a high-CP diet that contained approxi-mately 16% CP and 2.50 Mcal/kg of NE as well as five low-CP diets in which the CP level of the diet was reduced by approximately four percentage units but was supplemented with crystalline lysine, methio-nine, threonine, and tryptophan. The low CP diets provided 2.64, 2.58, 2.50, 2.42, or 2.36 Mcal/kg in Exp.1 as well as 2.45, 2.40, 2.35, 2.30, or 2.25 Mcal/kg in Exp.2. In Exp. 1, a linear(P=0.03)increase in weight gain was observed with decreasing NE level while the ratio of gain to feed was unaffect-ed(P > 0.05)by NE level. There was a linear in-crease(P=0.01)in the percentage of fat-free lean and a linear decrease(P=0.03)in the percentage of total fat with decreasing NE levels. In Exp. 2, a sig-nificant quadratic(P=0.03)effect of NE level was observed for weight gain. The ratio of gain to feed demonstrated a significant(P