Effect of dietary protein levels, lysine supplementation and stocking densities on laying hens performance [electronic resource].

Includes references.

A total number of 280 Bovans Brown Laying hens aged 24 weeks were randomely distributed into 8 groups in 2x2x2 factorial arrangement of treatments. Two dietary crude protein levels 16.5S. & 18.11% with two dietary supplemental lysine levels 0.00 & 0.1% the total dietary lysine become (0.83 & 0.93%) and (0.96 & 1.06%) for either dietary protein levels, respectively. Two stocking densities, 4 & 3 birds / cage (450 & 600 cm²/bird) were used. Feed was given in all mash form and offered with water ad - libitum under a total of 16 hours light daily. Results indicated that dietary protein levels showed no significant differences on egg production, egg quality, feed intake feed conversion, final body weight, body weight gain The 16.55% dietary crude protein showed significant (P≤0.05) effect on protein intake, and protein utilization than 18.11% CP. Dietary Lysine levels bad no effect on egg number, egg mass, egg quality, feed conversion, protein intake. The best final body weight, body weight gain and protein utilization showed significance (P≤0.05) with high dietary lysine supplementation level 0.1% than 0.00%. Stocking density showed significant (P≤0.05) increase in egg number, egg mass, final body weight, body weight gain when three birds were housed in cage. Yolk weight at 39 weeks of age as-stocking density increased (600 cm²/bird), while stoking density showed no significant difference in shell weight and shell thickness at 43 weeks of age, similar with decreasing stocking affect on (450 cm²/bird). Feed consumption was decreased significantly, while, feed conversion, protein intake and protein utili2ation were significantly (P≤0.05) improved by stocking density at 600 cm2/hen as compared with 450 cm2Ihen, while egg weight and egg quality were not significantly affected by different stocking density. The interaction effect of protein, lysine & stocking density showed no significant effect on egg number, egg mass, albumin weight, egg shape index at 39 wks of age, shell thickness and shape index at 43 wks of age. While, final body weight and body weight gain were significantly (P≤0.05) increased by 18.11% CP & 0.1% lysine (1.06% Lysine in the diet) & 600 cm2/hen stocking density interaction. However, treatments which fed diet at 18.11% CP with (0.96% lysine in the diet) lysine and 450 cm2/hen stocking density improved feed intake and feed conversion significantly (P≤0.05) compared with other treatments. Egg mass were significantly (P≤0.05) improved by protein level (16.55%), lysine (0.1%) stocking density (600 cm2/hen) interaction compared with other treatments. Protein intake and protein utilization were significantly(P≤0.05) improved for bens received diet containing 16.55% CP with 0.1% lysine and stocking density at 600 cm2/hen The economic parameters were affected by dietary protein or lysine supplementation and stocking density wherease decreasing protein level, increasing lysine supplementation and decreasing stocking density increase economic efficiency. It may be concluded that diets containing 16.55% CP and 0.1% Lysine supplementation (0.93% Lysine in the diet) with 600 cm2lhird would be ideal for the achievement of optimum revenue cost ratio for laying hens under Egyptian conditions.

Summary in Arabic.

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