The Division of Pathology, earlier existed as the Disease Investigation Section since 1939 at Izatnagar, got independent status on 6th September, 1963. In fact, it’s journey began from IVRI, Mukteswar, where it was functional from 1931 to 1945 in the name of the Section of Pathology, Serology and Bacteriology and then Section of Pathology and Bacteriology. The first account of diagnostic pathology was on ‘kumri’ initiated by Dr G.H.K. Mac Alister, an appointed Pathologist at Mukteswar Campus, in 1914. Subsequently, Dr Hugh Cooper published the first description of 'Ranikhet Disease' and Dr S. Dutta described the pathology of EBH and a number of new parasitic diseases. Later on, MCF, IBR, Chlamydial abortions, JD, Maedi/Visna, and a number of other infectious and non-infectious diseases of livestock and poultry were studied by eminent scientists under the Headship of Late Captain S.B.V. Rao, Drs Late B.S. Rajya, N.S. Parihar, Late P.K.R. Iyer, M.C. Prasad, Late O.P. Paliwal, R. Somvanshi and Rajendra Singh. Many of its pathologists, Drs G.C. Mohanty, M.C. Prasad, Lal Krishna, Nem Singh, Late H.K. Pradhan, S. Gopal Krishna S.C. Mukherjee and B.N. Tripathi also served the Institute/ the ICAR in the capacity of Directors, Joint Directors, ADG (AH) and DDG (AS). The Division, during its 58 years of existence, has made significant contributions in understanding the pathogenesis and pathology of important animal and poultry diseases, development of various diagnostic tests and vaccines, and human resource development through various programs. Presently, the Division is engaged in research related to retroviral diseases in small ruminants, Japanese encephalitis, porcine sapelovirus, cancer biomarkers in animals and important poultry diseases, etc. using conventional and molecular techniques. Besides, the Division also performs the work of diagnostic pathology of livestock, poultry, pets and wildlife diseases, histopathological evaluation of slides pertaining to various projects of the institutes, postgraduate teaching, training, research and maintenance of the Registry of Veterinary Pathology Museum. The museum houses more than thousand pathological specimens including neoplasms of various organ systems, which are being digitalised. The Division runs several out funded and institute funded projects with interdisciplinary and inter-institutional collaboration. The Division also provides consultancy to different agencies regarding livestock and poultry health management through timely precise diagnosis.