P.K. Trehan did his M.Sc. and Ph.D. in Animal Breeding from Punjab Agricultural University, Ludhiana. He has been extensively engaged in teaching undergraduate and postgraduate courses in Animal Breeding, Animal Genetics, Biostatistics and Computer Applications for about 30 years. Under his leadership as Chairman Academic Affairs Committee of the Department, the postgraduate course curriculum has been revised several times to incorporate the latest developments in Animal Breeding and Genetics. He has been guiding postgraduate students for their research work and helping students and staff members of the University for their Statistical Analysis. He has focused his research work on the genetic improvement of broilers. He had been principal investigator of the research project “AIRCP on Poultry Improvement(meat). He helped in the evolution of an outstanding strain of broiler developed in the university. He spread the computer culture in the university. He developed website of the university. He has authored a book on” Poultry Farming” and three laboratory manuals in the field of Animal Breeding, Animal Genetics and Biostatistics and Computer Applications. He is chairman of the Academic affairs Committee of the College of Veterinary Science. At present, Trehan is working as Professor of Animal Breeding, Department of Animal breeding and Genetics, Guru Angad Dev Veterinary and Animal Sciences University, Ludhiana. He took over the charge of  Librarian, GADVASU on 7^th August, 2006.