A. Z. Durrani, M. Ahmad, M. Ashraf, M.S. Khan, J.A. Khan, N. Kamal and N. Mumtaz
Deptt. of Clinical Medicine and Surgery, *Deptt. Of Pharmacology and Toxicology,
**Deptt. of Pathology, University of Veterinary and Animal Sciences, Lahore.
***Livestock and Dairy Development Deptt. Govt. of Punjab, Lahore.