CAIRO- Egypt's Juhayna Food Industries board has appointed Seif El Din Thabet as acting chairman, the company said in a statement a day after its chairman was arrested.

The company, Egypt's largest dairy products and juices producer, said on Wednesday it did not know the reason for Chairman Safwan Thabet's arrest.

Juhayna's shares were trading at 6.55 Egyptian pounds ($0.4174) at 0823 GMT on Thursday, up 1.6% after falling about 7% a day earlier after news of the arrest.

Two security sources told Reuters on Wednesday that Juhayna's chairman was detained for alleged "financial irregularities". The Interior Ministry has not commented.

($1 = 15.6925 Egyptian pounds)

(Reporting by Ehab Farouk; Writing by Mahmoud Mourad; Editing by) ((mahmoud.mourad@thomsonreuters.com))