Iranian Journal of Virology

fa Immunosuppression Viral Diseases in Healthy Broiler Flocks: The Pilot Study تخصصي Special پژوهشي Original article <div style="border-bottom:solid windowtext 1.0pt; border-top:solid windowtext 1.0pt; border-left:none; border-right:none; padding:1.0pt 0in 1.0pt 0in">Abstract Background and Aims: Immunosuppressive viral diseases have become a significant reason for mor-tality and economic losses in the poultry industry, mainly because of the increased susceptibility of to second bacterial infections and low responses to vaccination. The aim of this study, was to investigate the immunosuppressive viral agent, including IBDV, IBV, MDV, FadV, NDV, AIV, and CAV, in healthy farms. Bursas samples were collected from 3-4 week old broilers farm without clinical signs. One part of bursas fixed by immersion in 10% buffered formalin for histopathologic study and other parts selected for molecular studies. The RNA and DNA were extracted. PCR and RT-PCR were performed for this RNA and DNA viruses, respectively, and Phylogenetic analysis was conducted for IBD positive samples, also fixed tissue prepared for the histopathological purpose. Generally, four samples of 12 bursas samples were IBDV positive, five samples IBV positive (%41.66), and two samples MDV positive (16.66%). Interestingly these four IBDV positive samples showed the histopathological changes described above. According to the results of PCR and histopathology determine that % 33.33 of broilers farm in Iran are suffering from subclinical IBD. All samples for AIV, NDV, CAV, and IBH were negative in PCR detection methods. The phylogenic tree analysis results show that these sequences are similar to other IBDV strains circulating in Iran broiler farms and belong to very virulent IBDV genogroups.</div> Immunosuppression, Infectious bursal disease, Histopathology, PCR, Bursa of Fabricius 70 75 http://journal.isv.org.ir/browse.php?a_code=A-10-1-108&slc_lang=fa&sid=1 Arash Ghalyanchi-Langeroudi 10031947532846007874 10031947532846007874 Yes Department of Microbiology and Immunology, Faculty of Veterinary Medicine, University of Tehran, Tehran, Iran. Seyed Ahmad Madani 10031947532846007875 10031947532846007875 No Department of Animal and Poultry Health and Nutrition, Faculty of Veterinary Medicine, University of Tehran, Tehran, Iran. Naser Sadri 10031947532846007876 10031947532846007876 No Department of Microbiology and Immunology, Faculty of Veterinary Medicine, University of Tehran, Tehran, Iran. Zahra Ziafatikafi 10031947532846007877 10031947532846007877 No Department of Microbiology and Immunology, Faculty of Veterinary Medicine, University of Tehran, Tehran, Iran. Soroush Sarmadi 10031947532846007878 10031947532846007878 No Department of Microbiology and Immunology, Faculty of Veterinary Medicine, University of Tehran, Tehran, Iran. fahimeh Jamiri 10031947532846007879 10031947532846007879 No Department of Microbiology and Immunology, Faculty of Veterinary Medicine, University of Tehran, Tehran, Iran. Alireza Bakhshi 10031947532846007880 10031947532846007880 No Department of Microbiology and Immunology, Faculty of Veterinary Medicine, University of Tehran, Tehran, Iran. Omid Eghbali 10031947532846007881 10031947532846007881 No Department of Microbiology and Immunology, Faculty of Veterinary Medicine, University of Tehran, Tehran, Iran. Hossein Hosseini hosseini.ho@gmail.com 10031947532846007882 10031947532846007882 No Department of Clinical Sciences, Faculty of Veterinary Medicine, Karaj Branch, Islamic Azad University, Alborz, Iran.