1. Department of Microbiology, Parasitology, and Biotechnology, College of Veterinary and Biomedical Sciences, Sokoine University of Agriculture, Morogoro, Tanzania;
2. Department of Veterinary Surgery and Theriogenology, College of Veterinary and Biomedical Sciences, Sokoine University of Agriculture, Morogoro, Tanzania;
3. University of Texas at El Paso, El Paso, Texas