A. S. Abdalla1, A. A. Majok2, K. H. El Malik3 and A. S. Ali4*
1General Directorate of Animal Health and Epizootic Disease Control, Federal Ministry of Animal Resources and Fisheries, Khartoum, Sudan.
2Dr. John Garang Memorial University of Science and Technology, Bor, Sudan.
3Department of Preventive Medicine and Public Health, Faculty of Veterinary Medicine, University of Khartoum, Sudan.
4Department of Microbiology, Faculty of Medicine, King Khalid University, Abha, Saudi Arabia.
