1. The Central Laboratory for Evaluation of Veterinary Biologics (CLEVB), Agriculture Research Centre (ARC), Cairo, Egypt
2. Department of Poultry Diseases, Faculty of Veterinary Medicine, Cairo University, Giza, Egypt
3. Ceva-Phylaxia, Ceva Sante Animale, Cairo, Egypt
4. Ceva-Phylaxia, Ceva Sante Animale, Budapest, Hungary