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1.
J Avian Med Surg ; 35(3): 325-332, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34677031

RESUMEN

Beak and feather disease virus (BFDV), a circovirus, is the etiologic agent of psittacine beak and feather disease (PBFD), a progressive and often fatal disease in Psittaciformes. Even though neotropical psittacine species are more resistant to clinical infection than Old World species, BFDV is recognized as a threat to immunologically naïve wild psittacine flocks and its epidemiologic control is paramount for conservation efforts in Neotropical species. Samples were collected from multiple psittacine species, including Ara species, Amazona species, and the white-crowned parrot (Pionus senilis) from the only rescue center in Guatemala with formal psittacine rehabilitation and reintroduction programs. A total of 117 birds, with 101 adults and 16 juveniles of unknown sex, were tested for BFDV by means of a real-time polymerase chain reaction (PCR) assay. The BFDV prevalence found in this study was 0%, (95% confidence interval, 0%-6.0%). Seven 2-8-year-old scarlet macaws (Ara macao cyanoptera) with positive results from previous surveys by conventional PCR yielded negative results in this study, suggesting complete infection resolution.


Asunto(s)
Enfermedades de las Aves , Infecciones por Circoviridae , Circovirus , Psittaciformes , Animales , Pico , Enfermedades de las Aves/epidemiología , Aves , Infecciones por Circoviridae/epidemiología , Infecciones por Circoviridae/veterinaria
2.
Curr Microbiol ; 78(10): 3751-3756, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34468854

RESUMEN

Porcine circovirus type 3 (PCV3) is an emerging circovirus that is highly distributed among swine worldwide and associated with porcine dermatitis and nephropathy syndrome, reproductive failure, and multisystemic inflammation. Here, we investigated and characterized PCV3 from aborted fetuses in Vietnam. We found that the whole genomes of PCV3 collected in these Vietnamese pig farms share 98.4-99.45% sequence identity with reference PCV3 sequences. Several distinct mutation were identified in both the Rep protein and Cap protein of these strains. These strains were clustered into two distinct subtypes (3a1 and 3b). This study contributes to a better understanding of the molecular characteristics and genetic diversity of PCV3 in Vietnam.


Asunto(s)
Infecciones por Circoviridae , Circovirus , Enfermedades de los Porcinos , Feto Abortado , Animales , Infecciones por Circoviridae/veterinaria , Circovirus/genética , Femenino , Variación Genética , Filogenia , Porcinos , Vietnam
3.
Arch Virol ; 166(11): 3189-3192, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34524537

RESUMEN

Porcine circovirus type 2 (PCV2) is the etiological agent of post-weaning multisystemic wasting syndrome (PMWS). The original prevalent genotype, PCV2a, has been replaced by genotypes 2b and 2d in the swine population worldwide. The Rep protein is critical for viral replication. Comparison of a large number of Rep protein amino acid (aa) sequences showed that three sites distinguish genotype 2b from genotype 2d. In order to analyze the effect of exchanging the amino acids (asparagine and serine) at position 6 in the Rep proteins of PCV2b and PCV2d, two wild-type and two mutant viruses were rescued. Real-time quantitative PCR and a one-step growth curve were used to determine the viral load to assess the replication ability of the rescued viruses. The results showed that there was no significant difference in in vitro performance between the wild-type PCV2b and the mutated virus, while the mutation of PCV2d enhanced viral replication.


Asunto(s)
Infecciones por Circoviridae/virología , Circovirus/genética , Mutación , Proteínas Virales/genética , Replicación Viral/genética , Animales , Infecciones por Circoviridae/veterinaria , Circovirus/fisiología , Porcinos , Enfermedades de los Porcinos/virología , Carga Viral , Proteínas Virales/química , Proteínas Virales/metabolismo
4.
J Comp Pathol ; 187: 75-82, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34503658

RESUMEN

The objective of this study was to determine the pathogenicity of porcine circovirus type 2d (PCV2d) in pigs inoculated intranasally with PCV2d alone, PCV2d in combination with Mycoplasma hyopneumoniae or PCV2d in combination with porcine reproductive and respiratory syndrome virus (PRRSV). Pigs infected with PCV2d alone were asymptomatic. All pigs inoculated with either M. hyopneumoniae and PCV2d or with PCV2d and PRRSV developed porcine circovirus-associated disease (PCVAD), as characterized by a sudden onset of clinical signs and disseminated granulomatous inflammation. Inflammation was mainly present in lymph nodes and spleen, and occasionally in liver and kidney. Pigs in both of these dually infected groups also had significantly higher (P <0.05) microscopic lymphoid lesion scores and a significantly higher (P <0.05) number of PCV2-positive cells in lymph node tissue than did pigs inoculated with PCV2d alone. The M. hyopneumoniae and PRRSV combination potentiated the PCV2d load in the blood. Co-infection with PRRSV and PCV2d resulted in a significantly higher blood load of PCV2d compared with the M. hyopneumoniae and PCV2d combination. Successful reproduction of PCVAD in pigs appears to require PCV2d with at least one additional infectious agent, such as M. hyopneumoniae or PRRSV, for the full manifestation of disease.


Asunto(s)
Infecciones por Circoviridae , Neumonía Porcina por Mycoplasma , Síndrome Respiratorio y de la Reproducción Porcina , Enfermedades de los Porcinos , Animales , Infecciones por Circoviridae/veterinaria , Circovirus/patogenicidad , Coinfección/veterinaria , Mycoplasma hyopneumoniae/patogenicidad , Virus del Síndrome Respiratorio y Reproductivo Porcino/patogenicidad , Porcinos , Virulencia
5.
Vet Res ; 52(1): 120, 2021 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-34526128

RESUMEN

Gyrovirus 3 (GyV3), the third novel emerging species of the genus Gyrovirus of the Anelloviridae family, has been described in multiple hosts. Epidemiologically, there are suggestions that GyV3 is associated with diarrhea/proventriculitis, however, no direct causal evidence exists between GyV3 infection and specific clinical diseases. Herein, we infected special pathogen-free (SPF) chickens with GyV3, and then assessed the pathogenicity and tissue tropism. The results revealed that GyV3 induced persistent infection characterized by diarrhea, aplastic anemia, immunosuppression, and persistent systemic lymphocytic inflammation. Clinically, the infected chickens presented ruffled feathers, diarrhea, anemia, and weight loss. Aplastic anemia was characterized by progressive depletion of hematopoietic cells in the bone marrow, immunosuppression was associated with atrophy of the thymus, spleen, and bursa of Fabricious, progressive lymphocytic inflammations were characterized by proventriculitis, adrenalitis, pancreatitis, hepatitis, nephritis, and bronchitis. Viral loads of GyV3 in tissues exhibited "M", "N", "W" or "V" type dynamic changes. The highest level of viral loads was reported in bone marrow at 7dpi, followed by the adrenal gland at 2 dpi, the sciatic nerve at 7 dpi, and bile at 35 dpi. The bone marrow and kidney demonstrate the strongest immunostaining of GyV3-VP1 antigen and were suggested as the target tissues of GyV3. Collectively, GyV3 is an immunosuppressive pathogenic virus that targets the bone marrow and kidney in chickens. Exploring the pathogenicity and tissue tropism of GyV3 will guide the basic understanding of the biology of GyV3 and its pathogenesis in chickens.


Asunto(s)
Pollos , Infecciones por Circoviridae/veterinaria , Gyrovirus/fisiología , Gyrovirus/patogenicidad , Enfermedades de las Aves de Corral/virología , Tropismo Viral , Anemia Aplásica/inmunología , Anemia Aplásica/veterinaria , Anemia Aplásica/virología , Animales , Infecciones por Circoviridae/virología , Diarrea/inmunología , Diarrea/veterinaria , Diarrea/virología , Tolerancia Inmunológica , Inflamación/inmunología , Inflamación/veterinaria , Inflamación/virología , Cinética , Linfocitos/inmunología , Virulencia
6.
Vaccine ; 39(45): 6691-6699, 2021 10 29.
Artículo en Inglés | MEDLINE | ID: mdl-34538524

RESUMEN

Vaccines against porcine circovirus type 2 (PCV2) and Mycoplasma hyopneumoniae (Mhp) are routinely used by intramuscular injection. However, since intramuscular vaccination causes stress and increases the risk of cross-contamination among pigs, research on intradermal vaccination is currently being actively conducted. This study was designed to evaluate the efficacy of intradermally administered inactivated vaccines against PCV2 and Mhp in pigs. Three-week-old specific pathogen-free pigs were divided into three groups (5 pigs per group). Pigs in the two groups were intradermally vaccinated with the PCV2 or Mhp vaccine using a needle-free injector. Pigs in the third group were kept as nonvaccinated controls. At 21 days post-vaccination, pigs in one of these vaccinated groups and the nonvaccinated group were intranasally challenged with PCV2b and Mhp, while the other vaccinated group pigs were maintained as vaccine controls. Vaccine efficacy was evaluated by observing weight gain, pathogen load, pathological changes, and humoral or cellular immune responses. As a result, vaccinated pigs revealed significantly higher body weight gain, with lower clinical scores. Vaccinated pigs also showed higher antibody responses but lower PCV2b or Mhp loads in sera, nasal swabs, or lungs than nonvaccinated pigs. Intriguingly, vaccinated pigs upregulated cytotoxic T cells (CTLs), helper T type 1 cells (Th1 cells), and helper T type 17 cells (Th17 cells) after immunization and showed significantly higher levels of CTLs, Th1 and Th17 cells at 14 days post-challenge than nonvaccinated and challenged pigs. This study demonstrated that protective immune responses against PCV2 and Mhp could be efficiently induced in pigs using a relatively small volume of intradermal vaccines, probably due to effective antigen delivery to antigen-presenting cells in the dermis.


Asunto(s)
Infecciones por Circoviridae , Circovirus , Mycoplasma hyopneumoniae , Enfermedades de los Porcinos , Vacunas Virales , Animales , Anticuerpos Antivirales , Infecciones por Circoviridae/prevención & control , Infecciones por Circoviridae/veterinaria , Inyecciones Intradérmicas , Porcinos , Enfermedades de los Porcinos/prevención & control , Vacunas de Productos Inactivados
7.
BMC Vet Res ; 17(1): 308, 2021 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-34537035

RESUMEN

BACKGROUND: PCV3 is a pathogen associated with porcine dermatitis and nephropathy syndrome (PDNS)-like clinical signs, reproductive failure, and cardiac and multiorgan inflammation, which was newly identified in 2016 in sows in USA. Recently, PCV3 has also been identified from several non-porcine species like (cattle, dog, wild boar, deer, mice and ticks). However, PCV3 infection in donkey is not well established. Since 2019, 300 blood samples were collected from female donkey, which was characterized by abortion and sterility, in Liaocheng city of China. RESULTS: In the present study, an investigation of PCV3 in donkey blood samples was undertaken employing by real time PCR. Positive rates of PCV3 in donkeys reach to 21.0 %. In addition, one full-length PCV3 genome sequence was obtained, and it had a highest identity with porcine circovirus 3 PCV3/CN/Nanjing2017 strain and is clustered to PCV3a genotype based on ORF2 sequences. CONCLUSIONS: This is the first report of detection of PCV3 from female donkeys presenting reproductive failure in large-scale donkey farms, China. In addition, the PCV3 strain identified in this study shared the closest relationship with those from porcine, suggesting that PCV3 may be transmitted from pigs to donkeys. Totally, PCV3 infection in donkey should be concerned although the association between it and reproductive failure are not better understood.


Asunto(s)
Aborto Veterinario/virología , Infecciones por Circoviridae/veterinaria , Circovirus/clasificación , Circovirus/fisiología , Equidae , Infertilidad Femenina/veterinaria , Filogenia , Animales , Infecciones por Circoviridae/complicaciones , Infecciones por Circoviridae/diagnóstico , Infecciones por Circoviridae/virología , Circovirus/aislamiento & purificación , Femenino , Infertilidad Femenina/complicaciones , Infertilidad Femenina/virología
8.
Arch Virol ; 166(11): 3013-3021, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34402973

RESUMEN

In recent years, several novel circular single-stranded DNA viruses have been detected in various mammals, birds, insects, and environmental samples using metagenomic and high-throughput sequencing approaches. In this study, we tested for the presence of circoviruses in 243 bat fecal samples collected between 2018 and 2019 from 48 sampling sites across Korea. To detect circoviruses, nested PCR was performed with degenerate primers targeting a conserved replication-associated protein (rep) gene of circovirus/cyclovirus. Among 243 samples tested, a total of 37 fecal samples from 14 sampling sites were PCR-positive for circoviruses at a frequency rate of 15.23%. We obtained 36 partial rep gene sequences of circoviruses and one complete genome sequence of bat-associated circovirus 12, encompassing a genome size of 2097 nt containing two inversely arranged open reading frames and a conserved nonamer sequence in the apex of a stem-loop structure. In addition, we found four bat species that were harboring circoviruses in Korea based on species identification PCR of circovirus-positive bat fecal samples. Detailed sequence analysis indicated that the bat-associated circovirus sequences identified in this study were related to those of known bat and avian groups of circoviruses. Herein, we report evidence for the presence of bat-associated circoviruses in Korean bats.


Asunto(s)
Quirópteros/virología , Circovirus/genética , Circovirus/aislamiento & purificación , Filogenia , Animales , Infecciones por Circoviridae/veterinaria , Infecciones por Circoviridae/virología , Heces/virología , República de Corea
9.
Res Vet Sci ; 140: 79-82, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34416463

RESUMEN

A previous study has indicated that mRNA transcript of Rnf128 (Grail) is significantly increased in porcine epithelial cells expressing porcine circovirus type 2 (PCV2) open reading frame 5 (ORF5). RNF128 is an E3 ubiquitin ligase that can modulate the activity of target protein via ubiquitination of specific lysine residues. However, the function of RNF128 in PCV2-infected epithelial cells has not been well studied yet. Thus, the objective of the present study was to examine the functional role of RNF128 in porcine epithelial cells (PK15 cells) after PCV2 infection. Results clearly indicated that PCV2 ORF5 increased the expression of RNF128 which inhibited type I IFN production and enhanced viral replication of PCV2 in PK15 cells. Therefore, up-regulating RNF128 by PCV2 ORF5 can help PCV2 circumvent initial immune surveillance of porcine epithelial cells.


Asunto(s)
Infecciones por Circoviridae , Circovirus , Enfermedades de los Porcinos , Animales , Línea Celular , Infecciones por Circoviridae/veterinaria , Circovirus/genética , Células Epiteliales , Interferones , Sistemas de Lectura Abierta , ARN Mensajero/genética , Porcinos , Replicación Viral
10.
Transbound Emerg Dis ; 68(6): 2980-2989, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34406701

RESUMEN

Porcine circovirus type 3 has been circulating throughout the world and since their first report, various clinical signs and disease developments have been documented. The virus is similar to the closely related PCV2 and is associated with several clinical signs called porcine circovirus-associated diseases (PCVAD). PCV2 or PCV3 is occasionally reported with clinical signs such as PDNS, respiratory signs and reproductive failure. Retrospective research conducted in Thailand revealed that both PCV2 and PCV3 have been circulation for decades. However, awareness about PCV3 infection has just arisen in recent years because of the similarities observed in disease circulation and clinical signs that have led to concerns. This study was conducted to find the relationship between the quantity of PCV2 and PCV3 in Thai pigs displaying the clinical signs related to PCVAD. A total of 479 serum samples with different production phases and clinical signs were sent to Kamphaeng Saen Veterinary Diagnostic Center (KVDC) for qPCR to detect the presence of PCV2 or PCV3. There was no relationship between the PCV3 and PCVAD-related clinical signs. Also, the relationship between PCV2 and PCV3 with no clinical signs suggested that both viruses might come from the same reservoir or have been circulating in Thailand for a long time, leading to common incidents in finding. The viral load of PCV2 was significantly different among the pig groups with and without clinical signs. The capsid sequence analysis of PCV3 revealed that 22 capsid sequences obtained from this study were found as clusters within PCV3a with a minor variation. Additional control measures are further needed to reduce the findings of the viruses. A future study with a control experiment may be needed to clarify the pathogenesis of PCV3.


Asunto(s)
Infecciones por Circoviridae , Circovirus , Enfermedades de los Porcinos , Animales , Infecciones por Circoviridae/epidemiología , Infecciones por Circoviridae/veterinaria , Circovirus/genética , Epidemiología Molecular , Filogenia , Estudios Retrospectivos , Porcinos , Enfermedades de los Porcinos/epidemiología , Tailandia/epidemiología
11.
Vet Q ; 41(1): 232-241, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34380001

RESUMEN

BACKGROUND: Canine circovirus is reported in dogs in many countries, including the USA, China and Thailand. It has been detected in healthy dogs and dogs with diarrhea, hemorrhagic gastroenteritis, and vasculitis. It comprises five genotypes and is frequently found as a coinfection with canine parvovirus-2 (CPV-2). AIM: To characterize canine circovirus genotypes co-circulating with CPV-2 in Vietnam. METHOD: PCR assessment of 81 CPV-2-positive fecal samples from Vietnamese diarrheic dogs up to seven months of age for other viral enteric pathogens, including canine bocavirus, canine adenovirus, paramyxovirus, canine coronavirus, porcine circovirus-3 and canine circovirus. In addition, eight selected full genome sequences of Vietnamese canine circovirus were analyzed and used for phylogeny. RESULTS: In total 19.8% of samples were found to be positive for canine circovirus. Phylogeny revealed that the Vietnamese canine circovirus strains were clustered in two different genotypes (genotype-1 and -3). The genetic diversity among Vietnamese canine circovirus was 86.0-87.2%. The nucleotide discrepancy among both genotypes altered the deduced amino acid sequence in 14 and ten residues of the replicase and capsid proteins, respectively. Genetic recombination analysis revealed that the Vietnamese canine circovirus-6 strain has the American and Chinese canine circovirus as its major and minor parents, respectively. Only a single dog revealed triple detections of CPV-2c, Canine circovirus and canine adenovirus (1.2%). CONCLUSION: The co-circulation of two different genotypes of canine circovirus and CPV-2c in dogs in Vietnam has been illustrated. CLINICAL RELEVANCE: The mortality rate with CPV-2 only (22%) doubled in dogs with canine circovirus and CPV-2 co-infection.


Asunto(s)
Infecciones por Circoviridae/veterinaria , Circovirus/clasificación , Enfermedades de los Perros/virología , Secuencia de Aminoácidos , Animales , Proteínas de la Cápside/química , Infecciones por Circoviridae/epidemiología , Infecciones por Circoviridae/virología , Circovirus/química , Circovirus/genética , Circovirus/aislamiento & purificación , Enfermedades de los Perros/epidemiología , Perros , Genoma Viral , Genotipo , Recombinación Genética , Vietnam/epidemiología , Proteinas del Complejo de Replicasa Viral/química
12.
Microb Pathog ; 158: 105118, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34339795

RESUMEN

Porcine circovirus type 2 (PCV2) can cause various clinical diseases in pigs, resulting in huge losses for the pig farms all over the world. In order to develop a new strategy to control PCV2, it is essential to understand its mechanisms firstly, especially PCV2 interferes with the host's innate immunity. In the present study, lncRNA and mRNA expression profiles in porcine lymphnode response to PCV2 infection were deeply sequenced and analyzed. 3271 novel lncRNAs were identified in all. 1898 mRNAs and 282 lncRNAs showed differential expression between control and PCV2-infected groups. The bioinformatics analysis including lncRNA-mRNA co-expression network construction, as well as GO and KEGG pathway analysis focused on the DEGs was carried out. The results indicated that lncRNAs might participate in PCV2 infection-induced the pathogenesis of immunosuppression through regulating the host's immune responses, biological regulation, response to stimulus, cellular component organization or biogenesis and metabolism. And these differentially expressed lncRNAs might play important roles in response to PCV2 infection in the host's innate immune system. These findings provided a large-scale survey of dysregulated lncRNAs after PCV2 infection, especially the lncRNAs responded to host's innate immune within the lymphnode. This study will provide a novel insight into the lncRNAs' functions and the possible immunosuppressive mechanism induced by PCV2 infection. However, further research will be required to verify the characteristic function of the dysregulated lncRNAs.


Asunto(s)
Infecciones por Circoviridae , Circovirus , ARN Largo no Codificante , Enfermedades de los Porcinos , Animales , Infecciones por Circoviridae/veterinaria , Circovirus/genética , Biología Computacional , ARN Largo no Codificante/genética , ARN Mensajero/genética , Porcinos
13.
Vaccine ; 39(39): 5615-5625, 2021 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-34420789

RESUMEN

Porcine Circovirus type 2 (PCV2) associated disease is one of the most economically important swine diseases worldwide. Vaccines reduce PCV2 disease by inducing humoral immunity (neutralizing antibodies) and cell-mediated immunity (CMI) but may be improved by optimizing the immune response they induce. This study evaluated immune responses to a trivalent inactivated Porcine Circovirus (PCV) Type 1-Type 2a chimera (cPCV2a), cPCV2b and Mycoplasma hyopneumoniae (MH) (an experimental serial of Fostera® Gold PCV MH, also marketed as Circomax® Myco) vaccine or a bivalent recombinant PCV2a baculovirus expressed ORF2 capsid plus MH vaccine (Circumvent® PCV-M G2). Treatment Groups (T) received two doses of placebo (T01), one full or two split doses of the trivalent vaccine (T02, T03) or two split doses of the bivalent vaccine (T04) where two doses were given, there was a three-week period between administrations. All pigs were challenged with a virulent field isolate of PCV2d. CMI was measured as PCV2-specific IFN-γ secreting cells in blood and lymph node. Humoral immunity was measured as PCV2 antibodies. Vaccine efficacy was determined as viremia and fecal shedding of virus. There was a robust antibody response in T02 and T04 post the second vaccination and all vaccinated groups post challenge. There was a robust PCV2-specific IFN-γ response following the 1st dose in T02 and T03 and after the second dose in T02. T04 induced a low but detectable PCV2-specific IFN-γ response only after the 2nd dose. Among lymph node cells (study day 52), there was a significantly higher PCV2-specific, IFN-γ response to replicase and PCV2d capsid peptides in T01, consistent with active viral replication in non-vaccinated pigs. The trivalent chimeric vaccine induced robust CMI and protective efficacy, following a one dose regimen or splitting the dose into two vaccine administrations.


Asunto(s)
Infecciones por Circoviridae , Circovirus , Enfermedades de los Porcinos , Vacunas Virales , Animales , Anticuerpos Antivirales , Infecciones por Circoviridae/prevención & control , Infecciones por Circoviridae/veterinaria , Inmunidad Humoral , Porcinos , Enfermedades de los Porcinos/prevención & control , Vacunación
14.
J Vet Med Sci ; 83(8): 1263-1272, 2021 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-34234054

RESUMEN

The Cap of porcine circovirus type 2 (PCV2) can be assembled into virus like particles (VLPs) in vitro that have multiple loops located on the particle surface. This would make it a good vehicle for displaying exogenous proteins or epitopes. We derived two epitopes, epitope B (EpB, S37HIQLIYNL45) and epitope 7 (Ep7, Q196WGRL200) from Gp5 of the highly pathogenic porcine reproductive and respiratory syndrome virus (HP-PRRSV). We replaced the core region of Loop CD (L75PPGGGSN82) and the carboxyl terminus (K222DPPL226) of PCV2 Cap, respectively, to construct a bi-epitope chimeric PCV2 Cap. Its immunogenicity and protective effects were evaluated as one PRRSV subunit vaccine. The chimeric PCV2 Cap was soluble, efficiently expressed in an Escherichia coli expression system, and could be self-assembled into chimeric virus like particles (cVLPs) with a diameter of 12-15 nm. Western blotting confirmed that the cVLPs could be specifically recognized by anti-PCV2, anti-EpB and anti-Ep7 antibodies. The cVLPs vaccine could alleviate the clinical symptoms and reduce the viral loads after HP-PRRSV challenge in 100-120 days old pigs. These data suggest that the cVLPs vaccine could provide pigs with partial protection against homologous PRRSV strains, and it provides a new design for additional PRRSV subunit vaccines.


Asunto(s)
Infecciones por Circoviridae , Circovirus , Síndrome Respiratorio y de la Reproducción Porcina , Virus del Síndrome Respiratorio y Reproductivo Porcino , Vacunas Virales , Animales , Anticuerpos Antivirales , Infecciones por Circoviridae/prevención & control , Infecciones por Circoviridae/veterinaria , Circovirus/genética , Epítopos , Síndrome Respiratorio y de la Reproducción Porcina/prevención & control , Porcinos
15.
Vet Microbiol ; 260: 109182, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34315003

RESUMEN

Immunosuppression can increase the susceptibility of chickens to other disease-causing pathogens and interfere with the efficacy of vaccination against those pathogens. Chicken anaemia virus (CAV) and infectious bursal disease virus (IBDV) are common causes of immunosuppression in chickens. Immunosuppression was induced by experimental infection with either CAV or IBDV to assess the effect of immunosuppression on the efficacy of vaccination with Mycoplasma gallisepticum strain ts-304 against infection with virulent M. gallisepticum, a common bacterial pathogen of chickens worldwide. Birds were experimentally infected with either CAV or IBDV at 1 week of age, before vaccination and challenge with M. gallisepticum to examine the effect of immunosuppression at the time of vaccination, or at 6 weeks of age, after vaccination against M. gallisepticum but before challenge with virulent M. gallisepticum, to investigate the effect of immunosuppression at the time of challenge. All birds were vaccinated with a single dose of the ts-304 vaccine at 3 weeks of age and experimentally challenged with the virulent M. gallisepticum strain Ap3AS at 8 weeks of age. In immunosuppressed chickens there was a reduction in protection offered by the ts-304 vaccine at two weeks after challenge, as measured by tracheal mucosal thicknesses, serum antibody levels against M. gallisepticum, air sac lesion scores and virulent M. gallisepticum load in the trachea. Immunosuppressed birds with detectable serum antibodies against M. gallisepticum were less likely to have tracheal lesions. This study has shown that immunosuppression caused by infection with CAV or IBDV can interfere with vaccination against mycoplasmosis in chickens.


Asunto(s)
Infecciones por Birnaviridae/veterinaria , Virus de la Anemia del Pollo/inmunología , Pollos/inmunología , Infecciones por Circoviridae/veterinaria , Virus de la Enfermedad Infecciosa de la Bolsa/inmunología , Infecciones por Mycoplasma/veterinaria , Mycoplasma gallisepticum/inmunología , Enfermedades de las Aves de Corral/prevención & control , Sacos Aéreos/virología , Animales , Infecciones por Birnaviridae/prevención & control , Infecciones por Birnaviridae/virología , Virus de la Anemia del Pollo/patogenicidad , Pollos/microbiología , Infecciones por Circoviridae/prevención & control , Infecciones por Circoviridae/virología , Inmunidad Celular/inmunología , Inmunidad Humoral/inmunología , Inmunosupresión/veterinaria , Virus de la Enfermedad Infecciosa de la Bolsa/patogenicidad , Membrana Mucosa/virología , Infecciones por Mycoplasma/microbiología , Infecciones por Mycoplasma/prevención & control , Mycoplasma gallisepticum/patogenicidad , Enfermedades de las Aves de Corral/microbiología , Tráquea/virología
16.
Transbound Emerg Dis ; 68(6): 2957-2968, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34288522

RESUMEN

Porcine circoviruses are important pathogens of production swine. Porcine circovirus type 1 (PCV1) is non-pathogenic, and discovered as a contaminant of a porcine kidney cell line, PK-15. The discovery of pathogenic variant, PCV2, occurred in the late 90s in association with post-weaning multi-systemic wasting disease syndrome (PMWS), which is characterized by wasting, respiratory signs and lymphadenopathy in weanling pigs. A new PCV type, designated as PCV3, was discovered in 2016, in pigs manifesting porcine dermatitis and nephropathy syndrome (PDNS), respiratory distress and reproductive failure. Pathological manifestations of PCV3 Infections include systemic inflammation, vasculitis and myocarditis. A fourth PCV type, PCV4, was identified in 2020 in pigs with PDNS, respiratory and enteric signs. All the pathogenic PCV types are detected in both healthy and morbid pigs. They cause chronic, systemic infections with various clinical manifestations. Dysregulation of the immune system homeostasis is a pivotal trigger for pathogenesis in porcine circoviral infections. While the study of PCV3 immunobiology is still in its infancy lessons learned from PCV2 and other circular replication-associated protein (Rep)-encoding single stranded (ss) (CRESS) DNA viruses can inform the field of exploration for PCV3. Viral interactions with the innate immune system, interference with dendritic cell function coupled with the direct loss of lymphocytes compromises both innate and adaptive immunity in PCV2 infections. Dysregulated immune responses leading to the establishment of a pro-inflammatory state, immune complex associated hypersensitivity, and the necrosis of lymphocytes and immune cells are key features of PCV3 immunopathogenesis. A critical overview of the comparative immunopathology of PCV2 and PCV3/4, and directions for future research in the field are presented in this review.


Asunto(s)
Infecciones por Circoviridae , Circovirus , Enfermedades de los Porcinos , Animales , Biología , Infecciones por Circoviridae/veterinaria , Riñón , Porcinos
17.
Transbound Emerg Dis ; 68(6): 2949-2956, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34310859

RESUMEN

Porcine circovirus 3 (PCV3) is a recently discovered virus that has been detected in the swine population worldwide. PCV3 infection has been associated with several signs, but its pathogenicity is currently uncertain. This review article aimed to analyse the PCV3 strains that circulate in different countries in North and South America. We demonstrated the main regions of polymorphisms in the capsid protein structure. Furthermore, we found that PCV3 has at least six different lineages circulating in the Americas. Additional studies are required to determine the role of PCV3 in different clinical syndromes and its epidemiology in swine herds in North and South American countries.


Asunto(s)
Infecciones por Circoviridae , Circovirus , Enfermedades de los Porcinos , Animales , Infecciones por Circoviridae/epidemiología , Infecciones por Circoviridae/veterinaria , Circovirus/genética , Variación Genética , Filogenia , Porcinos , Enfermedades de los Porcinos/epidemiología
18.
Transbound Emerg Dis ; 68(6): 2975-2979, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34328270

RESUMEN

Porcine circovirus type 4 (PCV4) was first reported in 2019 in China. So far, the viral DNA was detected from both healthy and diseased pigs in China and South Korea by using molecular techniques including PCR and real-time PCR. In contrast, a serological survey regarding the presence of PCV4 antibodies in the pig population was seldomly reported. In the present study, we describe the development of an indirect enzyme-linked immunosorbent assay (ELISA) based on capsid protein for the detection of PCV4 antibodies in swine sera. After validating the specificity and sensitivity, the ELISA was used in a retrospective serological survey for PCV4 antibodies in pig sera from Jiangsu Province of China. Note that 3.44% of analyzed samples collected between 2018 and 2021 were tested positive for PCV4 antibodies. However, PCV4 genome was absent in all ELISA-positive serum samples. Therefore, the dynamic of viremia and antibody response to PCV4 infection in pigs warrant further investigation.


Asunto(s)
Infecciones por Circoviridae , Circovirus , Enfermedades de los Porcinos , Animales , Anticuerpos Antivirales , Infecciones por Circoviridae/diagnóstico , Infecciones por Circoviridae/epidemiología , Infecciones por Circoviridae/veterinaria , Ensayo de Inmunoadsorción Enzimática/veterinaria , Estudios Retrospectivos , Porcinos , Enfermedades de los Porcinos/diagnóstico , Enfermedades de los Porcinos/epidemiología
19.
Transbound Emerg Dis ; 68(6): 2969-2974, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34328681

RESUMEN

Porcine circovirus 3 (PCV-3) has been detected in diseased and healthy pigs of different ages. Several reports have associated the agent with reproductive failure and mummified and stillborn piglets. One report from North America has proposed a consistent potential association with postweaning disorders. Thus, the present case report aimed to describe the histopathological lesions and their association with the presence of PCV-3 genome in postweaning pigs showing growth-retardation and thrown-back ears. All affected animals displayed multi-organic lymphoplasmacytic periarteritis, lymphocytic myocarditis and/or lymphoplasmacytic meningoencephalitis. PCV-3 genetic material was detected by in situ hybridization within the lesions and confirmed by PCV-3 real-time quantitative PCR detection in tissues. This study represents the first report of PCV-3 associated with clinical disease in postweaning pigs in Europe.


Asunto(s)
Infecciones por Circoviridae , Circovirus , Enfermedades de los Porcinos , Animales , Infecciones por Circoviridae/veterinaria , Circovirus/genética , ADN Viral , Hibridación in Situ/veterinaria , Inflamación/veterinaria , América del Norte , Porcinos , Enfermedades de los Porcinos/epidemiología
20.
Trop Anim Health Prod ; 53(3): 371, 2021 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-34173084

RESUMEN

Porcine circovirus type 2 (PCV2), an important pig viral pathogen, can cause porcine circovirus-associated disease (PCVAD), resulting in economic losses associated with decreased growth and mortalities. The diagnosis of PCVAD is complex requiring clinical, pathological and virological approaches. This study assessed PCV2 infection using histopathology and immunohistochemistry (IHC) on tissue samples and quantitative polymerase chain reaction (qPCR) on serum samples from 47 grower-finisher pigs allocated in three clinical groups in the Philippines. Typical PCV2 histopathological lesions were observed in mediastinal lymph nodes (MLN) of eight of 47 pigs. Lymphoid depletion was seen in all eight pigs and granulomatous inflammation in one of these pigs. Four of these eight pigs were PCV2 positive by both IHC and qPCR. IHC revealed PCV2 antigen in 8 pigs in at least one of the following tissues: MLN (5/8), spleen (3/8), tonsils (4/8) and lungs (5/8). PCV2 antigen was observed in 3/8 MLN with lymphoid depletion and in one MLN with depletion and granulomatous inflammation. The qPCR test showed that 33 sera had a non-detectable level, twelve had < 106 and two had > 106 PCV2 DNA copies/ml serum. One pig with lymphoid depletion had > 106 PCV2 DNA copies/ml serum, and another pig without MLN lesions also had > 106 PCV2 DNA copies/ml serum. These findings suggest that PCVAD is present in the Philippines and confirm the challenges of PCVAD diagnosis as different patterns of results were obtained from the different tests.


Asunto(s)
Infecciones por Circoviridae , Circovirus , Enfermedades de los Porcinos , Animales , Anticuerpos Antivirales , Infecciones por Circoviridae/veterinaria , Ganglios Linfáticos , Filipinas , Porcinos
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