Distribution of avian infectious bronchitis virus subgenomic RNA in chickens

   Currently, the study of coronavirus infections, including those in birds, is relevant. The virus mainly replicates in the epithelial cells of the respiratory tract, causing lower respiratory tract infections in chickens. At the same time, virus replication in the intestine plays a key role in the development of coronavirus infection. In this study, the localization of preferential replication of the avian infectious bronchitis virus was studied based on the assessment of the ratio of genomic and subgenomic RNA of the AIB virus in the lungs, thymus and intestine. To model the avian infectious bronchitis, 14-day-old Shaver cross chickens were inoculated with a 10-fold dose of the vaccine strain of the avian infectious bronchitis (strain Ma5, serotype Massachusetts). During pathological examination, the thymus, intestine and lungs were collected for polymerase chain reaction (RT-PCR). The ratio of genomic and subgenomic RNA in the thymus, lungs and intestine was estimated as the ratio of threshold cycles in PCR for genomic RNA to threshold cycles for subgenomic RNA. Subgenomic RNA is formed directly in the infected cells. If there is more subgenomic RNA in the studied organ than genomic RNA, this may indicate active replication of the virus in this place. It has been proven that the source of the virus in the thymus is the replication process, and not hematogenous transport. A statistically significant prevalence of subgenomic RNA in the intestine (p ≤ 0.05) has been established, which indicates active replication of the coronavirus in the intestine and the predominant formation of a pool of viral particles in the lungs by the hematogenous and lymphogenous pathways.

1. Bhuiyan M.S.A., Amin Z., Bakar AM.SA, Saallah S., Yusuf N.H.M., Shaarani S.M., Siddiquee S. Factor influences for diagnosis and vaccination of avian infectious bronchitis virus (Gammacoronavirus) in chickens. Veterinary Sciences, 2021, vol. 8, no. 3, p. 47. DOI: 10.3390/vetsci8030047.

2. Dimitrov K.M., Ferreira H.L., Pantin-Jackwood M.J., Taylor T.L., Goraichuk I.V., Crossley B.M., Killian M.L., Bergeson N.H., Torchetti M.K., Afonso C.L., Suarez D.L. Pathogenicity and transmission of virulent Newcastle disease virus from the 2018–2019 California outbreak and related viruses in young and adult chickens. Virology, 2019, vol. 531, pp. 203–218. DOI: 10.1016/j.virol.2019.03.010.

3. Hasan I.I., Rasheed S.T., Jasim N.A., Shakor M.K. Pathological effect of infectious bronchitis disease virus on broiler chicken trachea and kidney tissues. Veterinary World, 2020, vol. 13, no. 10, p. 2203. DOI: 10.14202/vetworld.2020.2203-2208.

4. Fadhilah A.S., Kai T.H., Lokman H.I., Yasmin N.A.R., Hafandi A., Hasliza A.H., Tengku Rinalfi T.A., Hezmee M.N.M. Molecular and pathogenicity of infectious bronchitis virus (Gammacoronavirus) in Japanese quail (Coturnix japonica). Poultry science, 2020, vol. 99, no. 6, pp. 2937–2943. DOI: 10.1016/j.psj.2020.01.026.

5. Bande F., Arshad S.S., Omar A.R., Hair-Bejo M., Mahmuda A., Nair V. Global distributions and strain diversity of avian infectious bronchitis virus : a review. Animal health research reviews, 2017, vol. 18, no. 1, pp. 70–83. DOI: 10.1017/S1466252317000044.

6. Marandino A., Tomás G., Panzera Y., Greif G., Parodi-Talice A., Hernández M., Techera C., Hernández D., Pérez R. Whole-genome characterization of Uruguayan strains of avian infectious bronchitis virus reveals extensive recombination between the two major South American lineages. Infection, Genetics and Evolution, 2017, vol. 54, pp. 245–250. DOI: 10.1016/j.meegid.2017.07.009.

7. Lin J., Wang Z., Wang J., Yang Q. Microarray analysis of infectious bronchitis virus infection of chicken primary dendritic cells. BMC genomics, 2019, vol. 20, pp. 1–14. DOI: 10.1186/s12864-019-5940-6.

8. Mironova T.E., Afonyushkin V.N., Kozlova Yu.N., Bobikova A.S., Koptev V.Yu., Cherepushkina V.S., Sigareva N.A., Kolpakov F.A. Study of the protective effects of virocidal drugs on the model of coronavirus pneumonia. Veterinariya i kormlenie = Veterinaria i kormlenie, 2020, no. 7, pp. 35–38. (In Russian). DOI: 10.30917/ATT-VK-1814-9588-2020-7-10.

9. Nefedova E., Koptev V., Bobikova A., Cherepushkina V., Mironova T., Afonyushkin V., Shkil N., Donchenko N., Kozlova Y., Sigareva N. The infectious bronchitis coronavirus pneumonia model presenting a novel insight for the SARS-CoV-2 dissemination route. Veterinary Sciences, 2021, vol. 8 (10), p. 239. DOI: 10.3390/vetsci8100239.

10. Afonyushkin V.N., Akberdin I.R., Kozlova Y.N., Schukin I.A., Mironova T.E., Bobikova A.S., Cherepushkina V.S., Donchenko N.A., Poletaeva Y.E., Kolpakov F.A. Multicompartmental mathematical model of SARS-CoV-2 distribution. Mathematics, 2022, vol. 10, no. 11. DOI: 10.3390/math10111925.

11. Hoerr F.J. The pathology of infectious bronchitis. Avian Diseases, 2021, vol. 65, no. 4, pp. 600–611. DOI: 10.1637/aviandiseases-D-21-00096.