1. Department of Veterinary Clinical Studies, Faculty of Veterinary Medicine, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor Darul Ehsan, Malaysia.
2. Avian Unit, Veterinary Teaching Hospital, Ahmadu Bello University, P.M.B. 1045, Zaria, Nigeria.
3. Department of Veterinary Microbiology, Faculty of Veterinary Medicine, University of Maiduguri, P. M. B.1069, Maiduguri, Borno State, Nigeria.
4. Laboratory of Vaccines and Biomolecules, Institute of Bioscience, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor Darul Ehsan, Malaysia.
5. Department of Veterinary Pathology and Microbiology, Faculty of Veterinary Medicine, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor Darul Ehsan, Malaysia.