Researches on the Responses of Different Hybrid Layers with Respect to Egg Production Performances to Forced Molting Programs with and Without Feed Withdrawal

摘要

This research was carried out to determine the effects of four forced molting programs including three non-feed withdrawal programs (BB: Barley Based, WB: Wheat Bran based and OB: Oat Based) which supplied with alfalfa meal and one feed withdrawal method (FW: control 8 days FW + 34 days resting diet) on egg production performances of 320 brown (H and N Brown Nick) and 320 white (Hy-Line W-36) hybrid layers at 57 week of age. The experiment lasted totally 46 weeks including for 6 weeks molting period followed by a 40 weeks post molt production period. According to the results obtained, the genotype had significant (p<0.05) effect on body weight loss, feed consumption, hen day egg production (number%), cracked egg (%) and Heterophil:Lymphocyte (H:L) ratio (p<0.01) in molting period. Molting methods had significant (p<0.01) effects on body weight loss, feed consumption, hen-day egg production (number%) in molting period. In the production period; BB group had lower (p<0.05) hen-day egg production (%) than those of OB and FW groups. Feed efficiency values of WB group were better (p<0.05) than the values of OB and FW groups. As conclusion, after examining these production criteria, it can be stated that; non feed withdrawal methods, especially OB program can be used alternative to FW program. But, other non-feed withdrawal programs also can be used successfully as molting procedure.