Evaluation of dried vegetable residues for poultry: III Effects of feeding cabbage leaf residues on laying performance, egg quality, and apparent total tract digestibility

Abstract

The objective of the present study was to investigate the effects of feeding dried cabbage leaf residues (DCR) on egg production parameters, egg components, and egg fatty acid, cholesterol, and α-tocopherol concentrations and apparent total tract digestibility (ATTD). Seventy-two 34-week-old layers were randomly allotted to 4 dietary treatments: 0, 4, 8, or 12% DCR with 6 replicates with 3 birds each. Results showed that feed intake, egg production, and feed conversion ratio were unaffected by dietary treatments. Similar treatment effects also were observed for egg yolk and albumin percentages. However, eggshell percentage decreased (quadratic effect, P = 0.008) with increasing DCR. Egg yolk concentrations of α-tocopherol (linear effect, P <0.001), polyunsaturated fatty acids (linear effect, P = 0.0288), and linolenic acid (quadratic effect, P = 0.025) increased with increasing dietary DCR. However, inclusion of DCR had no influence on egg yolk cholesterol concentration. ATTD of dry matter (quadratic effect, P = 0.005), organic matter (quadratic effect, P = 0.008), neutral detergent fiber (quadratic effect, P = 0.0012), apparent metabolizable energy (quadratic effect, P = 0.0006), and apparent metabolizable energy corrected-nitrogen (quadratic effect, P = 0.0006) increased as the level of DCR in the diet increased. However, ATTD of crude protein and gross energy was similar among treatments. It was concluded that DCR can be fed to layers up to 12% without adverse effects on production parameters and may improve total tract nutrient utilization and egg quality.