RESUMO
Structural polypeptides of IVRI vaccine strain and two field isoaltes of Fowlpox virus (Bareilly isolate and Panchmahal isolate) were analysed on SDS-PAGE and by immunoblotting technique. In 5%-20% gradient acrylamide gel 31, 29 and 31 polypeptide bands and in 7.5%-15% gradient gel 45, 37 and 39 polypeptide bands were detected after Coomassie blue staining respectively for Bareilly isolate, Panchmahal isolate and IVRI vaccine strain. The molecular weight (MW) of the polypeptides ranged from 226.10 to 10.30 kDa with total MW of 2650.12, 2259.50, and 2378.68 kDa respectively for the three viruses. The immunoblot revealed 35, 29 and 30 immunogenic polypeptides indicating most virion polypeptides to be immunogenic in nature. Although most polypeptides had similar electrophoretic pattern both in SDS-PAGE and immunoblotting, still the three viruses could be differentiated. The viruses were found to be antigenically different with Panchmahal isolate lacking the polypeptides 81.15, 76.33, 39.30, 37.50 and 29.35 kDa and the vaccine strain lacking 76.33, 37.50 and 29.35 kDa polypeptides as were present in Bareilly isolate.