Response of layers to low nutrient density diets

Two experiments were conducted to test the ability of layers to increase their feed intake when fed diets of reduced nutrient density. Shaver White layers at 19 wk of age were fed diets at 2900 kcal ME/kg and 18.2% crude protein, or -5, -10, or -15% reduced nutrient density. In Experiment 1 reduced nutrient density was achieved by adding a non-nutritive filler. In Experiment 2 the same nutrient profiles were achieved by substitution of wheat, barley, and wheat bran for corn and fat. In Experiment 1, diet had no effect on egg production, egg size, or body weight since layers adequately adjusted their feed intake to normalize energy intake. Birds were less successful in adjusting feed intake in Experiment 2, and reasons for this are discussed. It is assumed that as long as nutrient balance is maintained in low nutrient density diets, diet equivalents even as low as 2465 kcal ME/kg and 15.2% CP are adequate to support full-cycle production.