SATYANARAYANA CHETTY, M (Major)SREENIVASULU, DSRI LATHA, ChALAHA SINGARI, NLAKSHMI KAVITHA, K2016-12-152016-12-152007-02http://krishikosh.egranth.ac.in/handle/1/90382THESESABSTRACT : Goat populations that are contributing to the greater extent to the economy of poor and marginal farmers of India are being threatened by a major devastating disease like Goatpox. The review of literature revealed meagre information on Goatpox and prophylactic vaccines to contain the disease. Hence, a modest attempt has been made to study on Goatpox with regards to epidemiology, isolation, characterization, diagnosis of viral agent and development of candidate vaccine strain. The seroepidemiological investigations revealed 72 per cent animals were positive for Goatpox. The animals co-habitated with Goatpox affected goats were uninfected. The disease was observed throughout Andhra Pradesh irrespective of breed, age and sex with casefatality rate of 13.3 per cent. The proviral clinical materials of infected goats were propagated in chicken embryos and VERO cell lines which yielded a titre of 0.5 x 102 to 1.4 x 103 EID50/ml and 4.8 to 6 TCID50/ml respectively. The isolates were purified by ultracentrifugation in 40-60 per cent sucrose density gradients. The isolates were confirmed by presence of lines of identity and a VNI of 3.2 to 3.6 against specific serum by subjecting to AGID and VNT respectively. The Goatpox virus was further confirmed by reproducing infection in experimental goats. Physico-chemical characterization of virus isolates revealed a temperature of 55°C for 60, 60°C for 30, 70°C for 10 min and the pH 3 and 5 were detrimental for viral infectivity. Further chloroform and ether completely inactivated the virus. The TEM observations at 39000 x magnification with TPT isolate revealed the morphology as brick shaped with 250±10 x 290±20 nm in size, while, IEM against specific antibody yielded aggregates of viral particles. The molecular studies of Goatpox virus with SDS-PAGE yielded 17 comigrating polypeptide profiles of which five were major and 12 minor, whereas RFLP studies on viral genome revealed 95 per cent homology among the four isolates. Among the conventional tests for the diagnosis I-ELISA was more sensitive and accurate with 72 per cent positives than AGID and CIE. The molecular diagnosis with PCR yielded a 470bp product which on sequence analysis exhibited 98 per cent homology with complete Goatpox viral genome available at database. Among vaccinates that were vaccinated with attenuated and inactivated vaccines yielded satisfactory immune responses and could withstand challenge.enGOATPOX; ISOLATION; MOLECULAR CHARACTERIZATION; candidate vaccine strainThesis