الفهرس | Only 14 pages are availabe for public view |
Abstract This study aimed to decrease the cost of the laying rations by lowering protein as it’s the most expensive constituent in the diet. So the research stated to investigate the effect of incorporating protease and/or formic acid as feed additives into low protein isocaloric diet of laying Japanese quail hens on the productive performance, egg quality, some serum biochemical parameters and carcass traits. It was performed on 120 of 5-6 week old healthy Japanese quail hens (weighed 268g±7.06) and randomly distributed into five groups (3 replicate per group). G1 (control with basal layer quail diet 20% protein), G2 (17%protien diet without protease enzyme or formic acid), G3 (17% protein diet + 0.05%protease enzyme), G4 (17%protein diet + 0.5%formic acid), G5 (17% protein diet + 0.05% protease + 0.5% formic acid). The experimental period lasted for 12 weeks with two weeks of adaptation before this period. For each replicate, daily egg number, daily egg weight and egg mass as well as weekly feed intake were recorded. At the end of each week, eggs were collected from each replicate to evaluate egg quality. Mean egg production, shape index, egg albumin weight, egg shell weight, egg yolk percent, carcass traits and most measured blood parameters in all groups had not differ significantly with control but G2 was numerically higher than control in egg production, egg mass, FCR, egg shell weight, albumin weight, egg yolk weight, dressing percentage, feed intake and weight losses at the end. G2 significantly has the heavier egg weight among groups (p<0.05) as the average egg weights were 11.77g and 12.48g in control and G2 respectively. G3 was the highest in feed intake and egg albumin percent among the other groups. G4 was the highest in egg shell percent. Triglycerides per whole yolk were lower in all groups than the control. Cholesterol (mg)/whole yolk was low in G2 and G3. FCR was improved in G5. G2 had the highest net revenue and economic efficiency (48 LE&114.3%) in compare with control (46 LE&106.98%), while the values were 47.1LE&107.3%, 43.3LE&101.4% and 46.2 LE&105.5% for groups G3, G4 and G5 respectively. It could be concluded that, feeding laying Japanese quail hens on diet containing 17% protein without protease or formic acid did not differ significantly than those on control diet containing 20% protein. Moreover, it showed numerical improvement than the control group regarding egg production, egg mass, FCR, egg shell weight, albumin weight, egg yolk weight, cholesterol in egg yolk and dressing percentage. Also, the low protein diet without any additives has the highest net revenue. |