EFFECT OF INTERACTION BETWEEN NUMBER OF DAY LIGHT HOURS AND DIETERY PROTEIN LEVELS ON PRODUCTIVE, PHYSIOLOGICAL AND IMMUNOLOGICAL PERFORMANCE OF TWO DEVELOPED STRAIN CHICKENS.

This experiment was carried out on the Matrouh and Silver Montazah strains which used 120 females + 12 males for  each strain to study the effect of interaction between number of day light hours and dietary protein levels on productive, physiological and immunological performance. The groups were as follows: The first group was taken 17 hours lighting /day + 16% dietary protein (control group); the second group was taken 17 hours lighting /day + 18% dietary protein; the third group was taken 15 hours lighting /day + 16% dietary protein; The fourth group was taken 15 hours lighting /day + 18% dietary protein. Theobtained results indicated that the group fed 18% dietary protein gave the lower feed intake and improved feed conversion compared with groups which take 16% dietary protein. The group reared under 17 h lighting /day + 16% dietary  protein gave the best egg weight and egg mass compared with  groups rearing under 15 h lighting /day and groups had18% dietary protein gave the high egg weight, egg mass and egg production % compared with  those  take 16% dietary protein. the higher values of egg shell thickness was for group fed 18% dietary protein compared with 16% dietary protein and the groups of Matrouh strain under 17 h lighting /day and 18% and 16% dietary protein and Silver Montazah under 17 h lighting /day and 18% dietary protein gave the higher fertility (%).Matrouh strain reared under 17 h lighting /day and using 18% dietary protein gave the higher values of PCV%, WBC's, lymphocytes, heterophils and H/L ratio. The groups take 17 h dietary /day gave the higher blood total protein level and total cholesterol compared with the groups take 15 h dietary /day. It could be concluded that the best of treated groups was  under 17 hour light/day plus preferred that diets containing 18% crude protein for improving productive, physiological and immunological performance for these developed strains in Egypt.