Abstract

    This project was designed to compare two routes (intraocular and drinking water) of vaccination against Newcastle disease in ten11s of protection against velogenic field isolate of Newcastle disease virus (NOV), The immune response and morphological changes in lymphoid organs (Harderian gland, bursa of fabricius and thymus) of broilers were noted. The role of Harderian gland to generate local and humoral immunity in response to eye drop and drinking water vaccination against NOV was also evaluated. This experiment showed that ocular vaccination resulted in significantly high level of circulating antibodies as compared to drinking water vaccination, No histopathological changes were observed in Iymphow organs after Nov challenge in ocularly vaccinated birds. There were significantly (P<0.05) higher number of plasma cells in sections of Harderian gland after eye drop vaccination, It was concluded that ocular vaccination stimulated Harderian gland to produce strong local protective immunity in ocular as well as in oral mucosa,

Key words: Newcastle disease, ocular route, drinking water, lymphoid organs, plasma cells.