Abstract
Circoviruses are circular single-stranded DNA (ssDNA) viruses that infect a variety of animals, both domestic and wild. Circovirus infection in birds is associated with immunosuppression and this in turn predisposes the infected animals to secondary infections that can lead to mortality. Farmed geese (Anser anser) in many parts of the world are infected with circoviruses. The majority of the current genomic information for goose circoviruses (GoCVs) (n = 40) are from birds sampled in China and Taiwan, and only two genome sequences are available from Europe (Germany and Poland). In this study, we sampled 23 wild and 19 domestic geese from the Gopło Lake area in Poland. We determined the genomes of GoCV from 21 geese; 14 domestic Greylag geese (Anser anser), three wild Greylag geese (A. anser), three bean geese (A. fabalis), and one white fronted goose (A. albifrons). These genomes share 83–95% nucleotide pairwise identities with previously identified GoCV genomes, most are recombinants with exchanged fragment sizes up to 50% of the genome. Higher diversity levels can be seen within the genomes from domestic geese compared with those from wild geese. In the GoCV capsid protein (cp) and replication associated protein (rep) gene sequences we found that episodic positive selection appears to largely mirror those of beak and feather disease virus and pigeon circovirus. Analysis of the secondary structure of the ssDNA genome revealed a conserved stem-loop structure with the G-C rich stem having a high degree of negative selection on these nucleotides.
Highlights
Circoviruses are non-enveloped, icosahedral viruses, with circular single-stranded DNA genomes which are approximately 2 kb in length.Transcription is bidirectional with a replication-associated protein (Rep) encoded on the virion sense strand and a capsid protein (CP) on the complementary sense strand [1,2]
Genome sequences (GenBank accession # KT808657; Figure S1) from a domestic Greylag goose was most closely related to a divergent goose circoviruses (GoCVs) sequence recovered from a Polish wild Greylag goose
The domestic geese sampled in this study were slaughter birds which were from parental flocks
Summary
Circoviruses (genus: Circovirus; family: Circoviridae) are non-enveloped, icosahedral viruses, with circular single-stranded DNA (ssDNA) genomes which are approximately 2 kb in length.Transcription is bidirectional with a replication-associated protein (Rep) encoded on the virion sense strand and a capsid protein (CP) on the complementary sense strand [1,2]. Viruses 2018, 10, 107 associated infections in birds is immunosuppression which is associated with the apoptosis of lymphocytes [3,4,5,6]. This immunosuppression can predispose circovirus infected birds to secondary infections by pathogenic bacteria, fungi, and viruses [7]. The prevalence of GoCV infections in domesticated geese (~20–56%) is similar to that noted for circovirus infections in pet/wild parrots (~20–64%) but generally lower than that for circoviruses infecting pigeons
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
