1. Department of Food Hygiene and Control, Faculty of Veterinary Medicine, University of Tripoli, P.O. Box 13662, Tripoli, Libya.
2. Department of Microbiology and Parasitology, Faculty of Veterinary Medicine, University of Tripoli, P.O. Box 13662, Tripoli, Libya.
3. Department of Food Hygiene and Control, Faculty of Veterinary Medicine, Suez Canal University, Ismailia 41522, Egypt.
4. Department of Food Hygiene and Control, Faculty of Veterinary Medicine, Cairo University, 12211 Giza 12211, Egypt.
5. Department of Genetics, The Lombardy and Emilia Romagna Experimental Zootechnic Institute, Via Bianchi 9, Brescia 25124, Italy.