Kumar, AshokSinha, Shreya2017-06-212017-06-212008http://krishikosh.egranth.ac.in/handle/1/5810022315PREVALENCE, IMMUNOPROPHYLAXIS AND MECHANISM OF IMMUNITY TO Sarcoptes scabiei INFESTATION IN PIGS.The thesis incorporates the results of investigation on the prevalence of Sarcoptes scabiei in and around Ranchi, immunization with whole mite extract antigen and induction of immune response in pigs as a result of immunization. Prevalence of S. scabiei in and around Ranchi was studied in accordance with age, breed, season and managemental condition like organized and unorganized pig farming. The overall seroprevalence of mites affecting pigs was estimated 56.81 percent in T& D and 70 percent in Desi. The age-wise prevalence indicated that pigs above 100 days of age were having the highest 42.85 percent in T & D and 84.37 percent in Desi and the animals up to 56 days age had the lowest 13.63 percent in T & D and 27.50 percent in Desi infestation. The desi pigs were found more susceptible to mite infestation as compared to T & D. Mite infestation was more common in winter ( 46.66 % T & D, 79.54 % Desi and 45.16% Landrace) and rainy season (40.90% T & D, 76.19 % Desi and 43.75%Landrace) as compared to summer season (21.73% T&D , 42.22 % Desi and 23.33% Landrace ). Hotel /Kitchen waste fed pigs were found more susceptible (47.82 %) as compared to grazing pigs ( 39.02% ) while mite infestation was more common in organized farm ( 60% ) as compared to unorganized farm ( 35.71% ) . Management wise mite prevalence study indicated that pigs maintained on kachcha floor were having the highest (82.93% ) and the pigs maintained on pacca floor were having lowest ( 64.44% ) infestation while in poor disease managemental condition pigs were found more susceptible ( 70% ) as compared to good managemental condition (22.85%). The result of the haematological studies showed that no significant change in haemoglobin and packed cell volume was found just after immunization . However, significant reduction in value was found on 90th and 150th day in group II and on 150th day in group I . In addition, the number of circulating lymphocytes, eosinophils and basophills significantly increased but neutrophil count decreased and these change was more marked on 30th and 60th day of observation. The results of the biochemical studies revealed that immunization resulted in significant decrease in albumin value. Reduction in the value was more marked on 30th and 60th day of observation. There was significant increase in serum globulin which is suggestive of an immunological response in the host to immunization. Intradermal injections of whole mite extract antigens resulted in the development of antigen –specific delayed hypersensitivity skin reaction in pigs immunized with WMEAg. Delayed type of hypersensitivity reaction was more pronounced at 48 hours, characterised by swelling and infiltration of large number of lymphocytes and macrophage . Serum precipitating antibodies to antigens of whole mite extract were detected by double immuno diffusion test . WME-Ag reacted with their homologous antisera but not with heterologous antisera indicating the presence of stage –specific antigens in whole mite extract . The presence of antibodies at the time when resistance was exhibited might indicate protective nature of antibodies . It appears, immunization with antigens comprising whole mite extract could afford better protection. Humoral antibody response of pigs to WMEAg when assessed by sandwich ELISA on day 0, 21, 60 , 90 and 150 showed significant difference in antibody level as compared to controls . However, significant antibody level could only be detected on 21st day post immunization which continued till day 150 with a peak on 21st , 60th and 90th day in group I and 21st day in group II . These results indicated significantly higher antibody level in immunized pigs and WMEAg is immunogenic From the results of the present investigation it is presumed that acquired resistance to S.scabiei in pigs has an immunological basis and the immune effector mechanism associated are hypersensitivity reactions mediated by anti –mite antibodies and cell mediated immunity.en-USnullThesis