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Anand Agricultural University, Anand

Anand Agricultural University (AAU) was established in 2004 at Anand with the support of the Government of Gujarat, Act No.(Guj 5 of 2004) dated April 29, 2004. Caved out of the erstwhile Gujarat Agricultural University (GAU), the dream institution of Sardar Vallabhbhai Patel and Dr. K. M. Munshi, the AAU was set up to provide support to the farming community in three facets namely education, research and extension activities in Agriculture, Horticulture Engineering, product Processing and Home Science. At present there seven Colleges, seventeen Research Centers and six Extension Education Institute working in nine districts of Gujarat namely Ahmedabad, Anand, Dahod, Kheda, Panchmahal, Vadodara, Mahisagar, Botad and Chhotaudepur AAU's activities have expanded to span newer commodity sectors such as soil health card, bio-diesel, medicinal plants apart from the mandatory ones like rice, maize, tobacco, vegetable crops, fruit crops, forage crops, animal breeding, nutrition and dairy products etc. the core of AAU's operating philosophy however, continues to create the partnership between the rural people and committed academic as the basic for sustainable rural development. In pursuing its various programmes AAU's overall mission is to promote sustainable growth and economic independence in rural society. AAU aims to do this through education, research and extension education. Thus, AAU works towards the empowerment of the farmers.

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19951
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Subject: Veterinary Microbiology × Author: Abraham, Reena × Start date: 1980 × Type: Thesis × Thesis Type: M.V.Sc. ×
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    ThesisItemOpen Access
    ANTIGEN DETECTION, PATHOGENICITY AND PERSISTENCE OF MATERNAL ANTIBODIES OF INFECTIOUS BURSAL DISEASE VIRUS
    (AAU, Anand, 1995) Abraham, Reena; Kher, H. N.
    Infectious bursal disease is an acute or more commonly a subclinical viral disease of young chickens characterized by lymphocidal effects in the lymphoid organs, especially in the bursa of Fabricius. The disease is known to cause immunosuppression, vaccinal failure and surfacing of latent and subclinical concurrent infection in the infected bird. Present study was aimed at the antigen detection, pathogenicity and persistence of maternal antibodies of infectious bursal disease virus (IBDV). The bursa samples were collected from the dead or ailing birds with specific IBD lesions routinely obtained at the Department of Pathology and were tested for the presence of the viral antigen using agar gel diffusion test (AGDT). The samples obtained from Anand, Karamsad, and Undach gave positive line oi precipitation with known positive serum. The isolates designated as AND (Anand), KAM (Karamsad) and UND (Undach) on the basis of the area from where these samples were obtained, were compared with a reference isolate BAN (Bangalore) for the pathogenicity study. Clinical symptoms were observed in one or two birds -from each group followed by death. Rest of the birds were normal till the end of the observation period . The bursa of Fabricius was found enlarged on the third day PI with gradual atrophy setting in from seventh day PI in all the infected groups. Spleen showed slight enlargement on seventh day PI. Thymus was found to be enlarged on 11th and 14th day PI. The bursa to body weight indices showed significant difference at different intervals. The indices showed that the bursa to body weight ratio in all the infected groups was about two times as compared to that of control on third day PI and from fifth day PI, there was a decrease in this ratio in all the infected group till the end of the observation period suggesting atrophy, The histopathological lesions were mainly seen in bursa of Fabricius (BF) in the form of marked inter and intrafollicular oedema and mild to moderate depletion of lymphoid cells on the third day PI. Mild increase in the interfollicular connective tissue proliferation along with heterophilic infiltration was also seen. The changes became severe on fifth day PI. On seventh day PI, the bursal follicles were atrophied with severe depletion of the lymphocytes in cortex and medulla. On 11th and 14th day PI, large cystic follicles with mononuclear cell infiltration into the interfol1icular area were observed. The spleen lesions were in the form of mild depletion of lymphoid cells along with focal areas of coagulative necrosis and reticulo-endothelial (RE) cell hyperplasia. The thymus and caecal tonsils revealed same type of lesions as spleen. The kidney revealed acute renal congestion and presence of lymphoid foci. The lesions were very mild in the AND and KAM groups of birds. The antigen was detectable in UND group on third day PI and BAN group on third and seventh day PI by AGDT. Using quantitative AGDT, serum antibodies were detected from seventh day PI onwards in the local isolate infected groups and from fifth day PI in the reference isolate infected group. 'The antibody titres showed gradual increase in all groups till the end of the observation'period. For immunosuppressive study, each infected group was vaccinated with sheep erythrocytes and subsequently at weekly interval birds from each group were screened for presence of antibody using HA test. Overall antibody level of control group was significantly higher (P < 0.01) from treatment means of infected group. Among BAN, KAM and AND isolates infected groups, mean HA titres did not show significant difference, but in UND isolate infected group the mean titre was significantly higher than other groups. Further, the infected birds were vaccinated with 'F' vaccine of NDV and each group was screened at weekly interval for presence of antibody using HI test. The HI titres of all the infected groups were significantly lower than that of control group at second and third week suggesting immunosuppressive effect of these isolates. The titres in AND and KAM groups were significantly lower than that in UND and BAN groups during this period indicating their more immunosuppressive effect. Only the UND isolate was adapted to the chick embryos producing mortality in four out of six chick embryos when inoculated via CAM route at fourth passage level. The embryoij were stunted with cutaneous haemorrhages in the cerebral area and on the toes. The other isolates did not adapt to embryos evenafter four passages. The maternal antibodies were found to persist in the chicks hatched from vaccinated parental flock upto 20 days of age as ascertained by ELIBA and quantitative AGDT. The maternal antibodies with the quantitative AGDT titre 1:8 and ELISA titre +3, were found to be protective only upto 15 days of age in chicks against IBDV infection.