PhD thesis by Amer Mohamed Abdel-Ati Abdel-Rasol, 2020
under supervision of;
1- Prof. Dr. Hassan Mohamed sobhy, Department of natural resources, Faculty of African post graduate studies, Cairo University.
2- Prof. Dr. Ali Meawad Ahmed, Department of food and hygiene, Faculty of Veterinary Medicine, Suez Canal University.
3- Prof. Dr. Sherein Saied Abdelgayed, Department of Pathology, Faculty of Veterinary Medicine, Cairo University.
