Graduating from the University of Queensland with first-class honours in Agriculture, Rodger Henry Watson was awarded a Council for Scientific and Industrial Research (CSIR) studentship. This allowed him to train at the Sir William Dunn Institute of Biochemistry (University of Cambridge) and at the Institute of Physiology at Gottingen, Germany. He returned to Australia in 1936 and soon took up a post at the McMaster Animal Health Laboratory in Sydney. There he worked on the physiology of digestion in ruminants. To further his research in this field, Watson moved to CSIR's Adelaide Animal Nutrition Laboratory.

In 1943 Rodger Watson was seconded from CSIR to become Officer-in-charge at Melbourne's Central Wool Testing House. Three years later he transferred to the nearby Animal Health Laboratory which was run by CSIR (subsequently CSIRO - Commonwealth Scientific and Industrial Research Organisation). His work there, which concentrated on the reproductivity of ewes and neo-natal mortality in lambs, had a major influence on the sheep industry world-wide.

Watson left CSIRO in 1961 to join the Victorian Department of Agriculture's S.S. Cameron Animal Research Laboratory as a senior livestock research officer. Later he became Chief of the Department's Division of Animal Industry. Rodger Watson also held many external positions including Federal President of the Australian Society for Animal Production, President of the World Association for Animal Production, Advisor to the Wool Production Research Advisory Committee, Fellow of the Australian Society for Animal Production and Fellow of the Australian Institute of Agricultural Science. He retired in 1977, but continued his affiliation with many of the above associations and boards