期刊：
Frontiers in Veterinary Science,2022年9:1169 ISSN：2297-1769
作者机构：
[Nan, Wenjin; Deng, Zhibang; Tan, Simin] Hunan Agr Univ HUNAU, Coll Vet Med, Hunan Prov Key Lab Prot Engn Anim Vaccines, Lab Anim Dis Prevent & Control & Anim Model, Changsha, Peoples R China.;[Nan, Wenjin; Wu, Jingbo; Peng, Guoliang; Hu, Honghui] Shaoguan Univ, North Guangdong Collaborat Innovat & Dev Ctr Pig F, Shaoguan, Peoples R China.
关键词：
Porcine circovirus type 2;Epidemiology;complete genome;Genetic characteristics;Guangdong Provine
摘要：
The emergence and widespread of porcine circovirus-associated diseases (PCVADs), mainly caused by porcine circovirus type 2 (PCV2), threatens the Chinese swine industry. In this study, to investigate the recent prevalence of PCV2 in northern Guangdong Province of China, 573 tissue samples from 132 pig farms were collected during 2016-2021 and analyzed via PCR. Overall, 51.38% (297/573, 95%CI 47.74-55.92) samples were tested PCV2 positive. The detection rate of PCV2 was significantly lower in samples collected before 2016-2018 than after the outbreak of African Swine Fever (2019-2021), being 59.85% (158/264, 95%CI 53.94-65.76) and 41.47% (141/340, 95%CI 36.43-46.71), respectively. On the other end, the genetic characteristics of 26 PCV2 strains were further analyzed. These PCV2 strains belonged to three genotypes, including PCV2a, PCV2b, and PCV2d. Specifically, the predominant genotype prevalent during two periods (2016-2018 and 2019-2021) wasPCV2b (81.82%, 9/11) and PCV2d (80.0%, 12/15), respectively. The results above illustrated the high prevalence and the genetic evolution feature of PCV2 in Guangdong Province in recent years.
摘要：
Porcine circovirus 2 (PCV2) is the causative agent of porcine circovirus-associated diseases (PCVADs). The infection of PCV2 is widespread and has serious consequence, thereby causing significant economic losses in the swine industry worldwide. Previously, we found that a strain named YiY-3-2-3 has a naturally occurring point mutation (G710 to A710) in ORF1 region, which leads to a shorten product of the rep gene (945 to 660 base pair). Importantly, the Rep protein is responsible for genome replication of PCV2. To explore the effects of this mutation on the PCV2 replication, in the current study we constructed infectious clone of this IF-YiY-3-2-3, as well as those of its two parental strains of IF-YiY-3-2-1 and IF-YiY-3-2-10. Subsequently, these infectious clones which have 1.1 copy of PCV2 genome of their corresponding strains were transfected into PK15 cells to obtain rescued viruses, respectively. Though all of the three infectious clones could be rescued, the copy number and infectivity of these rescued viruses were significantly different, as analyzed by fluorescence quantitative PCR, Tissue culture infectious dose 50 (TCID50), and indirect immunofluorescence assay (IFA). Notably, whether the PCV2 copy number, viral titer or the infectivity of rescued viruses from infectious clone IF-YiY-3-2-3 was significantly less than those of its parental clones. Meanwhile, the spatial structure of the Rep protein from the IF-YiY-3-2-3 displayed an apparent truncation at the C-terminal. These findings therefore suggest that the Rep protein with truncated C-terminal would reduce virus replication and infectivity, and there might also exist both favorable and unfavorable mutations in the ORF1 of PCV2 in the process of its evolution.
摘要：
T-2 and HT-2 toxins can cause cytotoxicity and oxidative stress in animals, while DL-Selenomethionine plays an important role in preventing oxidative stress and improving cell viability. However, the role of DL-Selenomethionine in T-2/HT-2 toxins-induced cell damage is still unknown. In this study, we investigated whether DL-Selenomethionine plays a protective role against T-2/HT-2-induced cytotoxicity and oxidative stress in primary hepatocytes. Our results demonstrated that T-2/HT-2 toxins-exposed broiler hepatocytes exhibited significantly decreased cell viability and intracellular glutathione (GSH) concentration while increased Lacate dehydrogenase (LDH) leakage, intracellular reactive oxygen species (ROS), glutathione peroxidase (GSH-PX), malondialdehyde (MDA) and catalase (CAT) levels, as well as elevated expression levels of genes related to oxidative stress, in a toxin dose-dependent manner (P < 0.05). However, the application of DL-Selenomethionine into T-2/HT-2 treated hepatocytes effectively alleviated the adverse effects of T-2/HT-2, as demonstrated by increased cell viability, decreased LDH leakage, declined intracellular ROS and MDA levels, increased expression of oxidative stress-related genes, as well as accordingly enhanced activities of GSH, GSH-PX, SOD and CAT as compared to the control groups (P < 0.05). Therefore, our in vitro data demonstrate that DL-Selenomethionine can function as an effectively protective agent against T-2/HT-2-induced cytotoxicity and oxidative stress.
摘要：
Porcine circovirus type 3 (PCV3) has recently been isolated from diseased pigs within the USA. The objective was to detect the presence of PCV3 in dogs. Nested polymerase chain reactions (PCR) with PCV3-specific primers for the capsid gene were used to detect PCV3 genomic DNA in serum samples from dogs (n = 44) in China. There was PCV3 DNA detected in 4 of 44 dogs [all were negative for PCV2 and canine circovirus (CanineCV)]. Based on sequence analysis, positive sequences were grouped into PCV3 genotypes. However, these isolates had close evolutionary relationships with FoxCV (KP941114) and CanineCV (JQ821392). Further investigations of the epidemiology, evolutionary biology, and pathobiology of PCV3 to dogs are warranted.
期刊：
POLISH JOURNAL OF VETERINARY SCIENCES,2017年20(1):25-29 ISSN：1505-1773
通讯作者：
Deng, Z. B.
作者机构：
[Pang, P.; Yuan, A. W.; Deng, Z. B.; Gong, Q. L.] Hunan Agr Univ, Coll Vet Med, Changsha 410128, Hunan, Peoples R China.
通讯机构：
[Deng, Z. B.] H;Hunan Agr Univ, Coll Vet Med, Changsha 410128, Hunan, Peoples R China.
关键词：
Life Sciences;Zoology;Life Sciences, other;Medicine;Veterinary Medicine
摘要：
Porcine circovirus type 2 (PCV2) has been known as a causative agent of reproductive failure in the sow. In the present study mouse model was used to investigate PCV2 infection. In order to investigate whether PCV2 can induce lesions of spermatocytes and oocytes, 6 male and 6 female mice were each inoculated intraperitoneally with PCV2b, and 3 male and 3 female mice mock-infected with cell culture supernatant served as controls. Samples of testes and ovaries from PCV2b-inoculated and mock-infected mice were investigated using PCR, histopathological, ultrastructural and immunofluorescent histochemical methods at 14 and 21 day post infection (dpi). The study revealed that in the virus-inoculated mice leydig cells in testes and granulosa cells in ovaries were degenerated, and a small number of spermatocytes and oocytes showed apoptosis. Positive PCV2b antigen signals were also observed in these apoptotic cells. It can be suggested that PCV2 can cause lesions of spermatocyte and oocyte prior to zygotes formation in its host.
期刊：
Archives of Virology,2017年162(7):2015-2020 ISSN：0304-8608
通讯作者：
Wang, Aibing
作者机构：
[Hu, Yi; Liu, Tanbin; Liu, Wei; Wang, Aibing; Lei, Hongyu] Hunan Agr Univ, Coll Vet Med, Res Ctr Reverse Vaccinol RCRV, Lab Anim Models & Funct Genom LAMFG, Changsha 410128, Hunan, Peoples R China.;[Zhan, Yang; Xie, Xiaohong; Wang, Naidong; Wang, Dongliang; Deng, Zhibang; Yang, Yi] Hunan Agr Univ, Coll Vet Med, Res Ctr Reverse Vaccinol RCRV, Lab Funct Prote LFP, Changsha 410128, Hunan, Peoples R China.
通讯机构：
[Wang, Aibing] H;Hunan Agr Univ, Coll Vet Med, Res Ctr Reverse Vaccinol RCRV, Lab Anim Models & Funct Genom LAMFG, Changsha 410128, Hunan, Peoples R China.
关键词：
PCV2 Strain;Major Open Reading Frame;PCV2 Genome;PCV2 Genotype;Porcine Circoviruses
摘要：
Porcine circovirus type 2 (PCV2) is the causative pathogen of porcine circovirus-associated diseases (PCVAD). This virus evolves mostly through point mutations and genome recombination between different PCV2 genotypes (e.g. PCV2a and PCV2b), as has been confirmed in swine herds. In the current work, the complete PCV2 genome sequences of 69 clones derived from various tissues (lymph node, spleen and lung,) of an infected individual, were subjected to phylogenetic and alignment analyses. The results not only demonstrate co-infection with distinct PCV2b subtypes (e.g. 1B and 1C) in the same animal, but also highlight another mechanism of evolution - diverse point mutations acquired during immune evasion by this virus.
