Widespread gyrovirus co-infections in backyard chickens in Türkiye: molecular and Phylogenetic insights.

INTRODUCTION

Gyroviruses are widespread small DNA viruses infecting poultry and other hosts, yet their diversity and coinfection dynamics in backyard systems remained poorly understood.

MATERIALS AND

METHODS

Tissue samples from 100 clinically healthy backyard chickens across five provinces in Türkiye, between 2020 and 2021, were screened using species-specific PCR assays targeting six gyroviruses.

RESULTS

The Gyroviral DNA was detected in 90.0% of samples (90/100), with CAV identified in 71.0% (71/100), AGyV2 in 59.0% (59/100), GyV3 in 8.0% (8/100), GyV4 in 22.0% (22/100), GyVTu789 in 19.0% (19/100), and GyV7-SF in 18.0% (18/100) of samples. Co-infections were frequent, most notably between CAV and AGyV2, with a co occurrence rate of 25.6%. Phylogenetic analysis of partial VP1 sequences revealed that circulating strains were largely consistent with global lineages, while also displaying detectable genetic variability, particularly within GyV4. Notably, GyVTu789 and GyV7-SF were identified for the first time in chickens in Türkiye, extending their known geographic range. The high rate of co-detection highlights the concurrent circulation of multiple gyroviruses in backyard poultry populations.

CONCLUSIONS

These findings provide a comprehensive overview of gyrovirus diversity and circulation dynamics, pinpointing the need for continued surveillance to better understand their epidemiology and potential impact on poultry health.