Pathological and molecular findings of visceral gout caused by Israel variant 2 (IS/1494/06) genotype of infectious bronchitis virus in chickens

Abstract

The aim of this study was to investigate pathological lesions and the presence of of Israel variant 2 (IS /1494/06) genotype of infectious bronchitis virus (IBV) in chickens with visceral gout. Sudden deaths were observed in broiler breeders and layer hens belonging to two different flocks located in eastern Turkey. Broiler chickens were previously vaccinated with a vaccine containing strains of IBV Massachusetts serotype, but no information was available about the vaccination history of laying hens. At necropsy, there was accumulation of white chalk-like material on the serosal surface of the heart, liver, spleen and air sacs. The kidneys were unilaterally or bilaterally enlarged and pale in color and, ureters were also enlarged. Pooled organ samples from diseased chickens and kidneys alone were examined by virus isolation, real-time reverse transcription polymerase chain reaction (rRT-PCR), nucleotide sequencing analysis and histological methods. Israel variant 2 genotype of IBV was detected in the samples of both flocks as a result of virus isolation, rRT-PCR and DNA sequencing analysis.Histological examination revealed multifocal and randomly distributed crystal deposits in the renal tubulus and adjacent interstitium. Mild to moderate crystalline deposits surrounded by heterophils and macrophages were detected in the serosal layers of the heart, spleen, liver, and air sacs. The findings of this study indicated that IBV should be taken into consideration in visceral gout cases of chickens, and detection of IBV genotypes in the field will enable us to use vaccines compatible with these genotypes in order to control the disease more efficiently.

Spike Glycoprotein 1 Partial Gene Analysis of GI-19 (QX-like) Infectious Bronchitis Virus Isolated and Propagated from Breeder, Broiler, and Layer Chickens in Java Region

“…Monitoring of IB in this study was carried out on breeder, broiler, and layer chickens. As reported before, IBV can infect various types of commercial chickens with various clinical manifestations (Bande et al 2016;Lounas et al 2018;Amarasinghe et al 2018;Wibowo et al 2019;Hassan et al 2022;Timurkaan et al 2021). In this study, we found reproductive symptoms (drop production and cystic oviduct), kidney urate deposits, and respiratory symptoms caused by QX-like strains.…”

“…Shell-less syndrome (SES) eggs associated with the Massachusetts (Mass) strain of IBV infection (Amarasinghe et al 2018), 4/91-like, and QX-like (Wibowo et al 2019) are another clinical manifestation of the reproductive tract. Timurkaan et al (2021) reported that cases of nephritis and visceral gout were clinical manifestations of the urinary system caused by the Variant 2 strain. The persistence of Australian T and Mass IBV strains has been reported to occur in the caecal tonsils for several months after infection (Najimudeen et al 2021).…”

“…IBV vaccines in Indonesia generally use virus seeds in the form of strains M41, H120, Connecticut, and local isolates (Dharmayanti and Indriani 2017;Wibowo et al 2019). Vaccinations that have been carried out on commercial broiler and layer chickens as well as breeders did not guarantee cross-protection for other IBV variants (Kahya et al 2012;Ghalyanchilangeroudi et al 2020;Ongor et al 2021). Vaccine cross-protection was reported to be very low between different IBV strains.…”