Performance of broilers fed diets with high and low net energy but similar metabolisable energy

Abstract

A semi-commercial scale feeding study was conducted to compare formulations of broiler diets based on predicted net energy (NE) and metabolisable energy (ME). It was hypothesised that formulating to NE may result in more efficient use of dietary energy, promoting optimal performance response in the birds. Dietary treatments contained higher or lower NE but with similar ME. Chickens fed the higher NE formulated diet had higher NE cost per weight gain (WG) and also higher productive energy (NEp) per body weight (BW) compared with birds fed the low NE diet. This resulted in a poorer performance in the high NE birds, such as lower WG, higher fat pad weight and decreased thigh meat yields. The results from this experiment did not confirm a beneficial effect of formulating diet based on NE, most likely due to lower protein level in the NE diet coupled with only a small increase in the NE content of the diet.