1. Department of Biological Sciences, Faculty of Science, University of Botswana, Private Bag 0022, Gaborone, Botswana
2. School of Allied Health Professions, Faculty of Health Sciences, University of Botswana, Private Bag 0022, Gaborone Botswana
3. Department of Biological Sciences and Biotechnology, Botswana University of Science and Technology, Private Bag 16, Palapye, Botswana