1Department of Surgery, College of Veterinary Science, Tirupati
2Bioproducts Lab, CLRI, Madras, College of Veterinary Science, Tirupati
3Department of Surgery, College of Veterinary Science, Tirupati
Acharya N.G. Ranga Agricultural University, Andhra Pradesh-517 502
†Part of M.V.Sc. thesis of first author approved by ANGR Agricultural University, Hyderabad.