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We isolated a strain of H9N2 avian influenza virus from a quail in southern China in May 2015 and named it A/quail/Guangxi/198Q39/2015. All eight gene segments of the strain were sequenced. Sequence analysis indicated that the amino acid motif of the hemagglutinin cleavage site of this H9N2 virus was RSSR↓GLF, which is a typical characteristic of the low pathogenic avian influenza virus. This study will help in better understanding the epidemiology and molecular characteristics of avian influenza virus in wild birds.

An H4N6 subtype avian influenza virus was isolated from a pockmark duck in southern China in November 2013 and named A/duck/Guangxi/149D24/2013 (H4N6). All eight gene segments of the strain were sequenced. Sequence analysis indicated that this H4N6 virus was a natural reassortant virus. This H4N6 virus has two basic amino acids in the cleavage site of hemagglutinin 1 (HA1) and HA2, and the amino acid motif of cleavage site was PEKASRGLF, which is the typical characteristic of the low-pathogenic avian influenza virus. This study will help understand the epidemiology and molecular characteristics of avian influenza virus in pockmark ducks.

Here, we report the complete genome sequence of an H6N6 avian influenza virus (AIV) isolated from a pigeon in Guangxi, southern China, in 2014. The eight RNA segment genes shared a high nucleotide identity (97 to 99%) with H6N6 subtypes of AIV isolated from ducks in the regions around Guangxi Province. The finding of this study will help us understand the ecology and molecular characteristics of H6 avian influenza virus in wild birds in southern China.

A field strain of H3N6 avian influenza virus (AIV), A/duck/Guangxi/175D12/2014(H3N6), was isolated from a native duck in Guangxi Province, southern China, in 2014. All of the eight AIV gene segments were sequenced, and sequence results revealed that there were 11 amino acid deletions at the NA stalk region. The NA, PB2, and NP genes showed highest homology to H5N6 AIV, and the PA gene showed highest homology to H7N2 AIV. Phylogenetic analysis indicated that the eight AIV gene segments belonged to the Eurasian lineage. These findings provide scientific evidence of possible or potential mutations of H3N6 AIV circulating in waterfowl in southern China.

A duck tembusu virus (DTMUV) was isolated from the brain of a Cherry Valley duckling that showed neurological signs by using a specific-pathogen-free chicken embryo. The isolate was named GX2013G (GenBank accession no. KM275941). The strain GX2013G was identified with reverse transcription-PCR (RT-PCR), and the amplicon was sequenced. The genome that was obtained is 10,990 nucleotides in length and contains a single open reading frame encoding a putative polyprotein of 3,425 amino acids. This study will advance the understanding of the epidemiology and molecular characteristics of tembusu virus (TMUV) in Guangxi and further studies of the mechanisms of virus replication and pathogenesis.

We report the complete genomic sequence of the full Muscovy duck parvovirus (MDPV) strain, designated GX2011-5, isolated from a Muscovy duck in Guangxi Province, China. The complete genomic sequence was 5,132 bp in length and contained two major open reading frames encoding a 1,844-nucleotide (nt) nonstructural protein and a 2,199-nt capsid protein. Comparison of the complete sequence of GX2011-5 with other published sequences of Muscovy duck parvovirus revealed that this strain exhibited 90.4% to 95.1% sequence homology. This report will advance our understanding of the epidemiology and molecular characteristics of MDPV in the Muscovy duck population in Guangxi, China.

We report here two complete genome sequences of porcine circovirus 2. The complete genomes of BH5 and BH6 were amplified and analyzed. Sequence analysis demonstrated that strains BH5 and BH6 belonged to PCV2d and PCV2b, respectively. Knowledge regarding the complete genome sequences of strains BH5 and BH6 will be useful for epidemiological surveillance.

We report here the complete genome sequence of a novel reassortant H4N2 avian influenza virus strain, A/duck/Guangxi/125D17/2012(H4N2) (GX125D17), isolated from a duck in Guangxi Province, China in 2012. We obtained the complete genome sequence of the GX125D17 virus isolation by PCR, cloning, and sequencing. Sequence analysis revealed that this H4N2 virus strain was a novel reassortant avian influenza virus (AIV). Information about the complete genome sequence of the GX125D17 virus strain will be useful for epidemiological studies.

We report here the complete genome sequence of a duck Tembusu virus (DTMUV) strain, GX2013H, isolated from a duck from Cheery Valley in the Guangxi Province of southern China in 2013. We obtained the strain GX2013H from a Cheery Valley duck with severely decreased egg production and neurological signs. The genome of GX2013H is 10,990 nucleotides (nt) in length and contains a single open reading frame encoding a putative polyprotein of 3,425 amino acids (aa). A comparison of the complete sequence and the deduced amino acid sequence of GX2013H with published sequences of 15 other chicken anemia viruses from China showed that the homologies of the nucleotides are approximately 96.5% to 97.5% and the homologies of the deduced amino acid sequences are approximately 98.9% to 99.3%. This report will help to understand the epidemiology and molecular characteristics of TMUV in Guangxi.

We report here the full-length RNA genomic sequence of the bovine viral diarrhea virus (BVDV) strain GX4, isolated from a cow in southern China. Studies indicate that BVDV GX4 belongs to the BVDV-1b subtype. This report will help in understanding the epidemiology and molecular characteristics of BVDV in southern China cattle.

We report here the complete genome sequence of a triple-reassortant H1N1 swine influenza virus strain, A/swine/Guangxi/BB1/2013 (H1N1) (GXBB1), isolated from a swine in the Guangxi Province of southern China in 2013. We obtained the complete genome sequence of the GXBB1 virus. Sequence analysis demonstrated that this H1N1 virus was a triple-reassortant swine influenza virus (SIV) whose genes originated from avian, human, and swine, respectively. Knowledge regarding the complete genome sequence of the GXBB1 virus will be useful for epidemiological surveillance.

We report the complete genomic sequence of a novel Newcastle disease virus (NDV) strain, duck/China/Guangxi19/2011, isolated from a white duck in Guangxi Province, southern China. Phylogenetic analysis based on a fusion gene comparison with different NDV strains revealed that duck/China/Guangxi19/2011 is phylogenetically close to genotype IX NDV, and the deduced amino acid sequence of the fusion protein cleavage site was 112R-R-Q-R-R-F117. The whole nucleotide sequence had the highest homology (99.7%) to the sequence of strain F48E8 (GenBank accession number FJ436302). This study will help us understand the epidemiology and molecular characteristics of genotype IX Newcastle disease virus in ducks.

We report here the complete genome sequence of a novel H1N2 avian influenza virus strain, A/Sparrow /Guangxi/GXs-1/2012 (H1N2), isolated from a sparrow in the Guangxi Province of southern China in 2012. All of the 8 gene segments (hemagglutinin [HA], nucleoprotein [NP], matrix [M], polymerase basic 2 [PB2], neuraminidase [NA], polymerase acidic [PA], polymerase basic 1 [PB1], and nonstructural [NS] genes) of this natural recombinant virus are attributed to the Eurasian lineage, and phylogenetic analysis showed that those genes are derived from H1N2, H3N1, H3N2, H4N6, H6N2, H10N8, H5N1, and H4N6 avian influenza viruses (AIVs). The amino acid motif of the cleavage site of HA is PSIQSR↓GLF. The sequence analysis will help in understanding the molecular characteristics and epidemiology of the H1N2 influenza virus in sparrows.