Résumé
Examined field chickens with signs and lesions of natural infection with necrotic enteritis [NE] revealed the isolation of Clostridium perfringens [C. perfringens] from positive chickens at the rate of 63.33%, 30%, 30% and 66.66% in autumn, winter, spring and summer; respectively. The overall positive samples were 57 out of examined 120 chickens with incidence of 47.5%. Regarding chicken breed, isolation rate in autunm were 65% and 60.0%, in winter 35.0% and 20.0%, in spring 25.0% and 40.0%, in summer 85.0% and 30.0% was recorded out of broilers and layers; respectively. C. perfringens isolates were serologically typed into 24 type A, 3 type C and 30 nontoxigenic isolates. Type A isolates were 5, 2, 6 and 11 in autumn, winter, spring and summer; respectively. While type C isolates were 2 in autumn and 1 in spring. C. perflingens Type A recovered from broiler and layer were 2 and 3, 2 and 0, 4 and 2, 10 and 1 in autumn, winter, spring and summer; respectively. Only 2 isolates of type C were recovered in autumn and I in spring