Molecular detection and genetic diversity of porcine bocavirus in piglets in China

Abstract

Porcine bocavirus (PBoV) is a recently discovered, non-enveloped and single-stranded DNA virus that can infect pigs. In order to understand PBoV infection and its genetic characterization in piglets in Xinjiang China, PBoV was detected by PCR in 156 clinical samples from 1-month-old piglets. PBoV was detected in 9 clinical samples, with a prevalence rate of 5.77% (9/156). Then nonstructural protein NS1 gene was amplified, sequenced and used for phylogenetic analysis. The results showed that the prevalence rate in the sick piglets was 9.33% (7/75), which is significantly higher than that in the healthy piglets (2.47%, 2/81). The nucleotide sequences of NS1 gene share high identities (96.1-99.2%) within the same groups of PBoVs. Phylogenetic analysis based on complete nucleotide sequence of NS1 gene showed that PBoV strains can be classified into three genetic groups, among which group I contains PBoV1 strains, group II contains PBoV2 strains, and group III contains PBoV3, PBoV4 and PBoV5 strains. Porcine/XJ-12, porcine/XJ-27, porcine/XJ-65, and porcine/XJ-145 had close genetic distance with subgroup 1, belonging to group I; strains porcine/XJ-79 and porcine/XJ-134 were clustered with subgroup 2, belonging to group II, while porcine/XJ-8, porcine/XJ-52 and porcine/XJ-96 were clustered with subgroup 3, which belonged to group III. This study demonstrated for the first time that PBoV strains in Xinjiang belong to three subgroups of three different genetic groups, indicating a substantial genetic diversity of the epidemic strains circulating in China, which provided the useful epidemiological data for scientific control and prevention of this disease in farm pigs.

Porcine Bocavirus: A 10-Year History since Its Discovery

“…In China, the prevalence rate of PBoV in stool samples of piglets was found to be 12.59% (Cheng et al 2010). Similarly, the prevalence rate of bocaviruses in clinical samples from one-month-old piglets was reported to be 5.77% (9/156) (Meng et al 2018). Another study reported that the prevalence rate of PBoV was 18.1% (84/463) (Zhou et al 2018).…”

“…Lymph nodes, spleen, and tonsil have the highest detection rate suggesting that these organs are the sites of active replication and the pathogenesis of PBoV infections may involve the lymphoid tissues and gastrointestinal tract (Jacob et al 2018). Besides tissues, bocavirus has been detected from the saliva (Choi et al 2014) and serum (Csagola et al 2012;Choi et al 2014;Meng et al 2018). In brief, bocavirus has been isolated from different tissues of the pig, but it is still not clear which cells in pigs are responsible for its multiplication and dissemination throughout the body.…”

“…The infection rates of PBoV in the PMWS-affected pigs were twice higher than in the non-PMWS affected pigs. The co-infection of PBoV along with the TTSV and PCV-2 might have facilitate the development of PMWS Blomström et al (2009) The co-existence of two bocavirus strain within the same fecal sample revealing inter and intra host genetic diversity Lau et al (2011) The genetic diversity of the circulating bocavirus strains in Xinjiang belong to three subgroups of three different genetic groups Meng et al (2018) Gastrointestinal tract…”

Identification and Genomic Characterization of Two Novel Porcine Circovirus Like Virus Strains Associated with Severe Diarrhoea and Hemorrhagic Enteritis in Piglets in China

“…The primers of Viruses including PEDV, PDCoV, TGEV, RV, SADS-CoV, PTV, PKV, PBV, PBoV, SaV, PSV, NOV and PCV4 have been found from the literature [4][5][6][7][8][9][10][11][12][13]. 5 prime pairs were designed based on the reference sequence of the PCL virus 21 and 22 strain determined in the United States and the PCL virus GX14, GX15 and GX19 detected in China (Table 1).…”

“…Newborn piglets are highly vulnerable to some enterovirus infections, causing severe diarrhea, enteritis and vomiting. Enteric pig viruses include porcine epidemic diarrhoea virus (PEDV), porcine delta coronavirus (PDCoV), porcine transmissible gastroenteritis virus (TGEV), swine acute diarrhoea syndrome coronavirus (SADS-CoV), porcine sapelovirus (PSV), porcine rotavirus (RV), porcine picobirnavirus (PBV), porcine circovirus 4 (PCV4), porcine teschovirus (PTV), porcine kobuvirus(PKV), porcine bocavirus(PBoV), porcine sapovirus (SaV), porcine circovirus-like virus(PCL virus) and porcine norovirus (NoV), was detected at porcine farms in China [4][5][6][7][8][9][10][11][12][13].…”