Prabhakaran, VDhinakaran, ManormaAppaji Rao, VNTANUVAS2022-08-012022-08-011993https://krishikosh.egranth.ac.in/handle/1/5810185997TNV_CRN_1993_22(1)29-32The baseline study on RD immunity done on batches A and B using 50 and 30 chicks respectively, revealed the following: (1) Chicks which were vaccinated with RDVF on the 7th day and challenged with RD virulent virus on the 28th day showed a survival rate of 130 percent while chicks which were challenged on 49th day showed only 73.3 per cent survivability.EnglishVeterinary ScienceArticle