Article History
Received: 21 September 2018
Accepted: 6 January 2019
First Online: 19 January 2019
Compliance with ethical standards
:
: Ethical clearance for this study was obtained from the animal research ethical review committee of Addis Ababa University, College of Veterinary Medicine and Agriculture, with reference number of approval letter VM/ERC/15/05/10/2018.
: The authors declare that they have no conflict of interest.