تأثير شدة الإضاءة في الأداء الإنتاجي لفروج اللحم المربى تحت درجات حرارة بيئية مرتفعة

Abstract EN

One day old straight chicks ( Fawbro ) were used to study the effect of low light intensity during the hot hours on the day on some productive and physiological traits of broilers reared under high cyclic temperature ( 28-36-28 cْ ).

Two treatments were used as follows ( T1) the birds were exposed to lower light intensity 0.5 -0.7 Lux for 12 hours during the hot period on the day ( 9 a.m.

to 9 p.m .

) and followed by 15-16 Lux for 12 hours ( 9 p.m to 9 a.m ) .

( T2) the birds were exposed for constant light intensity 15-16 Lux for 24 hours continuously .

Result revealed low light intensity 0.5-0.7 Lux significantly ( p<0.05 ) increased the average of body weight at 8 weeks of age , quantity of consumption feed and total weight gain means during the period 4-8 weeks of age .

as result revealed significantly decrease ( p<0.05) in mortality and Heterophils / Lymphocytes ( H / L ) ratio for low light intensity ( T1 ) compared with ( T2 ) that light intensity 15-16 Lux for 24 hr.