Effect of Dietary Protein Levels and some Limiting Amino Acids on the Performance of Egg-Type Commercial Pullets (20-40 Weeks)

A feeding trial was conducted using 372 commercial pullets, from 20 weeks to 40 weeks of age following 3 x 5 factional arrangement in completely randomised design (CRD). Three dietary levels of lysine (0.75, 0.70 and 0.65%) and methionine+cystine (0.60, 0.55 and 0.50%) were compared at three different levels of protein (18% CP in Treatments 1 to 5, 16% CP in Treatments 6 to 10 and 14% CP in Treatments 11 to 15) with one negative control having all vegetable protein and one positive central (vegetable protein dict+5% fish meal) at each protein level. Maximum per cent hen day production was obtained at the high protein level. Higher and similar values for feed efficiency were noticed at high and medium level in comparison to low level of protein. Levels of protein and amino acids had no effect on egg weight. Feed conversion efficiency improved significantly (p<0.05) at low level supplementation of amino acids and was poor for the sole vegetable protein diet. The diets having all -vegetable protein, fish meal and medium level of amino acid exhibited comparable but poor feed conversion efficiency. Vegetable protein, animal protein and low level of amino acid supplemented groups had similar effect on body weight gains. Gains observed on medium level of amino acid supplemented groups were also comparable to the pre-stated groups. However; high level of amino acid supplemented groups projected poorest gains.