Abstract
The present study was conducted to explore the effects of some factors affecting the productive and economic efficiency of Hy-Line layer breed in El-Menofia governorate. Data was collected from accurate records present in the farms and from structural questionnaire method during period from 2000 to 2018 on 29 cycles. The aim of this study is to determine and highlight the most important factors affecting the efficiency of Hy-Line breed and their profitability under Egyptian conditions. The study revealed that forced molting had a significant effect (P<0.05) on productive efficiency parameters. Highest values of all productive and economic efficiency parameters as feed amount, total egg number, total return and net profit were in molting cycles (75.71, 530.29 , 368.88,and 69.81LE, respectively) compared to non molting cycles(46.56, 351.07, 284.95 and 48.31 LE, respectively). Also, year non significantly affected total feed amount and total egg production, lowest value of total feed amount and total egg production obtained in year after 2016. Mortality percent significantly differ among different years; highest value of mortality percent was 35.73 % in years between 2000 to 2008. While, all parameters of economics including different costs and return showed a significant difference (P<0.05) increase gradually with increasing years showed lowest value in 2000 to 2008 and highest value after 2016. So we concluded that prices of different inputs and output was increased in last few years and molting is economic factor for improve productive and economic efficiency.

Key words: Layer, molting, production efficiency, Economic efficiency