Ovarian Morphology and Egg Quality Traits of Egyptian Selected Strain for Egg Production Compared with Commercial Laying Strains
ABSTRACT An experiment was conducted to evaluate the effect of selection for egg production performance of Cairo L-2 strain, as a local layer strain, after five generations of selection on productivity, ovarian morphology and some egg quality traits versus commercial Lohmann Brown-Lite (LBL) strain. The performance in the 5th generation was evaluated in Cairo L-2 and LBL strains for live body weight at sexual maturity (BWSM), age at sexual maturity (ASM), first egg weight (FEW), ovarian morphology, ovarian follicles number, ovarian weights and diameter, oviduct weight, liver weight, and stroma weight and their percentages to live body weight at sexual maturity for Cairo L-2 and LBL strains. Egg traits at 36 weeks of age including: egg number (EN), egg weight (EW), shell thickness (ST), and shell index (SI) were also obtained. Current results indicated that Cairo L-2 strain had higher ASM compared with LBL strain. Also, Cairo L-2 strain had lower BWSM, oviduct, ovary, stroma, and liver absolute weights and relative ovary weight compared with LBL strain. Ovarian follicles number, weights and diameter, FEW, and EN until 36 weeks of age were higher in LBL than in Cairo L-2 strain. Also, SI of the LBL was higher than that of Cairo L-2 strain. Moreover, Cairo L-2 strain egg production until 36 weeks of age was about 80% of that of LBL strain with good ST and SI. In conclusion, there were positive responses in ovarian morphology, egg production, and egg quality traits of Cairo L-2 strain associated with breeding program.