University of Tehran Press Journal of Veterinary Research 2008-2525 52 3 1997 10 23 - - 14602 FA Journal Article Enzootic calf-pneumonia is a common disease of calves in dairy farms in Tehran. A virological and serological study was carried out during 1992-1994. Two hundred and twenty nine calf pneumonia were diagnosed clinically and samples were taken for virological and serological examinations. Infectious Bovine Rhinotracheitis Virus (IBR) was the most commonly isolated virus (46 cases) in cultured samples. Other viruses such as Parainfuluenza type 3 (PI3), Adeno, Bovine Viral Diarrhea Virus (BVD) and Bovine Respiratory Syncytial Virus (BRSV) were identified 13, 4, 3 and one cases, respectively. Serological findings showed that the prevalences of seropositive calves for IBR, PI3, BVD and BRSV viruses were 93.8%, 80.5%, 41.0% and 17.4%, respectively. Vaccination againsts viral agent of enzootic calf pneumonia, preferably IBR and PI3, can be considered as a preventive measure. Enzootic calf-pneumonia is a common disease of calves in dairy farms in Tehran. A virological and serological study was carried out during 1992-1994. Two hundred and twenty nine calf pneumonia were diagnosed clinically and samples were taken for virological and serological examinations. Infectious Bovine Rhinotracheitis Virus (IBR) was the most commonly isolated virus (46 cases) in cultured samples. Other viruses such as Parainfuluenza type 3 (PI3), Adeno, Bovine Viral Diarrhea Virus (BVD) and Bovine Respiratory Syncytial Virus (BRSV) were identified 13, 4, 3 and one cases, respectively. Serological findings showed that the prevalences of seropositive calves for IBR, PI3, BVD and BRSV viruses were 93.8%, 80.5%, 41.0% and 17.4%, respectively. Vaccination againsts viral agent of enzootic calf pneumonia, preferably IBR and PI3, can be considered as a preventive measure. https://jvr.ut.ac.ir/article_14602_2548e0a7d08ca169af9729e03206e6a1.pdf