Institution: | (1) Central Veterinary Research Laboratory, P.O. Box 8067, Al Amarat, Khartoum, Sudan;(2) Department of Microbiology, Faculty of Veterinary Medicine, University of Khartoum, Shambat, 13314 Khartoum North, Sudan;(3) Biotechnology Research Unit, Animal Reproduction Research Institute, P.O. Box 12556, Al-Aharam, Giza, Egypt;(4) Atbara Veterinary Research Laboratory, Atbara, River Nile State, Sudan |