Diverse amdoparvoviruses infection of farmed Asian badgers (Meles meles).

Amdoparvoviruses infect various carnivores, including mustelids, canids, skunks, and felids. Aleutian mink disease virus (AMDV) belongs to the prototypical species Amdoparvovirus carnivoran1. Here, we identified a novel amdoparvovirus in farmed Asian badgers (Meles meles), and we named this virus "Meles meles amdoparvovirus" (MMADV). A total of 146 clinical samples were collected from 134 individual badgers, and 30.6% (41/134) of the sampled badgers tested positive for amdoparvovirus by PCR. Viral DNA was detected in feces, blood, spleen, liver, lung, and adipose tissue from these animals. Viral sequences from eight samples were determined, five of which represented nearly full-length genome sequences (4,237-4,265 nt). Six serum samples tested positive by PCR, CIEP, and IAT, four of which had high antibody titers (> 512) against AMDV-G. Twenty-six of the 41 amdoparvovirus-positive badgers showed signs of illness, and necropsy revealed lesions in their organs. Sequence comparisons and phylogenetic analysis of the viral NS1 and VP2 genes of these badger amdoparvoviruses showed that their NS1 proteins shared 62.6%-88.8% sequence identity with known amdoparvoviruses, and they clustered phylogenetically into two related clades. The VP2 proteins shared 76.6%-97.2% identity and clustered into two clades, one of which included raccoon dog and arctic fox amdoparvovirus (RFAV), and the other of which did not include other known amdoparvoviruses. According to the NS1-protein-based criterion for parvovirus species demarcation, the MMADV isolate from farm YS should be classified as a member of a new species of the genus Amdoparvovirus. In summary, we have discovered a novel MMADV and other badger amdoparvoviruses that naturally infect Asian badgers and are possibly pathogenic in badgers.

First detection of Tetraparvovirus ungulate 1 in diseased cattle (Chinese Simmental) from Hunan province, China.

Tetraparvovirus is an emerging parvovirus infecting a variety of mammals and humans, and associated with human diseases including severe acute respiratory infection and acute encephalitis syndrome. In the present study, a Tetraparvovirus ungulate 1 (formerly known as bovine hokovirus) strain HNU-CBY-2023 was identified and characterized from diseased Chinese Simmental from Hunan province, China. The nearly complete genome of HNU-CBY-2023 is 5346 nt in size and showed genomic identities of 85-95.5% to the known Tetraparvovirus ungulate 1 strains from GenBank, indicating a rather genetic variation. Phylogenetic and genetic divergence analyses indicated that Tetraparvovirus ungulate 1 could be divided into two genotypes (I and II), and HNU-CBY-2023 was clustered into genotype II. This study, for the first time, identified Tetraparvovirus ungulate 1 from domestic cattle from mainland China, which will be helpful to understand the prevalence and genetic diversity of Tetraparvovirus ungulate 1.

Recombination and amino acid point mutations in VP3 exhibit a synergistic effect on increased virulence of rMDPV.

Recombinant Muscovy duck parvovirus (rMDPV) is a product of genetic recombination between classical Muscovy duck parvovirus (MDPV) and goose parvovirus (GPV). The recombination event took place within a 1.1-kb DNA segment located in the middle of the VP3 gene, and a 187-bp sequence extending from the P9 promoter to the 5' initiation region of the Rep1 ORF. This resulted in the alteration of five amino acids within VP3. Despite these genetic changes, the precise influence of recombination and amino acid mutations on the pathogenicity of rMDPV remains ambiguous. In this study, based on the rMDPV strain ZW and the classical MDPV strain YY, three chimeric viruses (rZW-mP9, rZW-mPR187, and rYY-rVP3) and the five amino acid mutations-introduced mutants (rZW-g5aa and rYY-5aa(ZW)) were generated using reverse genetic technology. When compared to the parental virus rZW, rZW-g5aa exhibited a prolonged mean death time (MDT) and a decreased median lethal dose (ELD50) in embryonated duck eggs. In contrast, rYY-5aa(ZW) did not display significant differences in MDT and ELD50 compared to rYY. In 2-day-old Muscovy ducklings, infection with rZW-g5aa and rYY-5aa(ZW) resulted in mortality rates of only 20% and 10%, respectively, while infections with the three chimeric viruses (rZW-mP9, rZW-mPR187, rYY-rVP3) and rZW still led to 100% mortality. Notably, rYY-rVP3, containing the VP3 region from strain ZW, exhibited 50% mortality in 6-day-old Muscovy ducklings and demonstrated significant horizontal transmission. Collectively, our findings indicate that recombination and consequent amino acid changes in VP3 have a synergistic impact on the heightened virulence of rMDPV in Muscovy ducklings.

Detection of canine parvovirus type 2c (CPV-2c) in Palestine.

INTRODUCTION: The objective of the present study was to report, for the first time, the presence of canine parvovirus type 2c (CPV-2c) in domesticated dogs with acute gastroenteritis and to characterize the antigenic variants circulating in Palestine. METHODOLOGY: A veterinary clinical-based epidemiological study was carried out between December 2022 and April 2023. Fifty fecal samples were collected from dogs with gastroenteritis and screened for CPV-2 infection by polymerase chain reaction. The distribution of positive cases according to various epidemiological factors was studied. Partial sequencing of the viral protein 2 (VP2) gene was performed for the analysis of CPV-2 variants. RESULTS: Most of the investigated samples (60%; n = 50) during the study period were found positive for CPV-2 infection. There was no difference in the distribution of positive cases of CPV-2 infection based on age group, gender, location, and vaccination status. The analysis of nucleotide and amino acid sequences from amplified products, as well as phylogenetic analysis, revealed the presence of CPV-2c clustered with Asian CPV-2c variants. CONCLUSIONS: In summary, this study represents the initial genetic analysis of CPV-2 present in Palestinian dogs with gastroenteritis and provides evidence that confirms the existence of the CPV-2c variants. To determine the prevailing CPV-2 variant associated with the infection, it is crucial to conduct further sequence analysis using large populations of both domestic and wild canines.

Determination and Characterization of Novel Papillomavirus and Parvovirus Associated with Mass Mortality of Chinese Tongue Sole (Cynoglossus semilaevis) in China.

A massive mortality event concerning farmed Chinese tongue soles occurred in Tianjin, China, and the causative agent remains unknown. Here, a novel Cynoglossus semilaevis papillomavirus (CsPaV) and parvovirus (CsPV) were simultaneously isolated and identified from diseased fish via electron microscopy, virus isolation, genome sequencing, experimental challenges, and fluorescence in situ hybridization (FISH). Electron microscopy showed large numbers of virus particles present in the tissues of diseased fish. Viruses that were isolated and propagated in flounder gill cells (FG) induced typical cytopathic effects (CPE). The cumulative mortality of fish given intraperitoneal injections reached 100% at 7 dpi. The complete genomes of CsPaV and CsPV comprised 5939 bp and 3663 bp, respectively, and the genomes shared no nucleotide sequence similarities with other viruses. Phylogenetic analysis based on the L1 and NS1 protein sequences revealed that CsPaV and CsPV were novel members of the Papillomaviridae and Parvoviridae families. The FISH results showed positive signals in the spleen tissues of infected fish, and both viruses could co-infect single cells. This study represents the first report where novel papillomavirus and parvovirus are identified in farmed marine cultured fish, and it provides a basis for further studies on the prevention and treatment of emerging viral diseases.

Molecular characterization of full-length VP2 gene of canine parvovirus type 2 strains circulating in Egypt 2019-2021.

Canine parvovirus type 2 (CPV-2) is a major cause of fatal gastroenteritis and myocarditis in puppies of domestic and wild carnivores. CPV-2 has accumulated changes over time lead to the emergence of three antigenic variants CPV-2a, CPV-2b, and CPV-2c. VP2 is the major capsid protein that determines virus antigenicity, and host range. Although the three CPV-2 variants were previously identified in Egypt, most reports covered a restricted geographic region and/or time period, and only analyzed partial fragments of VP2 gene. Therefore, this study was designed to test 100 rectal swabs collected from 7 Egyptian governorates between 2019 and 2021 for CPV-2 using PCR. A total of 65 positive samples were identified, mostly in pure dog breeds of young age. The three variants co-circulated in 2019, while CPV-2b was not detected in 2020 and 2021. The frequency of CPV-2b and CPV-2c was higher in 2019 and 2021, respectively. Analysis of CPV-2 full-length VP2 gene sequence from 19/65 positive samples has identified four common amino acid substitutions F267Y, S297A, A300G, Y324I, which are characteristic for the new CPV-2 variants currently circulating worldwide. Unique substitutions including A5G, G36R, V38E, Q370R, and G392V were recognized in certain samples, and appears to have distinct effect on receptor binding, nuclear translocation, and inter-species transmission. Phylogenetic analysis showed separation of CPV-2 strains into two clades. All strains of this study were classified in clade I with Asian strains. In conclusion, this study provides updated comprehensive molecular analysis of CPV-2 variants in Egypt.

Proteomics analysis of PK-15 cells infected with porcine parvovirus and the effect of PCBP1 on PPV replication.

Porcine parvovirus (PPV) is one of the most important pathogens that cause reproductive failure in pigs. However, the pathogenesis of PPV infection remains unclear. Proteomics is a powerful tool to understand the interaction between virus and host cells. In the present study, we analyzed the proteomics of PPV-infected PK-15 cells. A total of 32 and 345 proteins were differentially expressed at the early and replication stages, respectively. Subsequent gene ontology annotation and Kyoto Encyclopedia of Genes and Genomes enrichment analysis showed these differentially expressed proteins were significantly enriched in pathways including toll-like receptor signaling pathway, tumor necrosis factor signaling pathway, and viral carcinogenesis. The expression of poly (rC) binding protein 1 (PCBP1) was observed to decrease after PPV infection. Overexpressed or silenced PCBP1 expression inhibited or promoted PPV infection. Our studies established a foundation for further exploration of the multiplication mechanism of PPV. IMPORTANCE: Porcine parvovirus (PPV) is a cause of reproductive failure in the swine industry. Our knowledge of PPV remains limited, and there is no effective treatment for PPV infection. Proteomics of PPV-infected PK-15 cells was conducted to identify differentially expressed proteins at 6 hours post-infection (hpi) and 36 hpi. Gene ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analysis showed that various pathways participate in PPV infection. Poly (rC) binding protein 1 was confirmed to inhibit PPV replication, which provided potential targets for anti-PPV infection. Our findings improve the understanding of PPV infection and pave the way for future research in this area.

Opportunistic sampling of yellow canary (Crithagra flaviventris) has revealed a high genetic diversity of detected parvoviral sequences.

Parvoviruses are known to be significant viral pathogens that infect a wide range of species globally. However, little is known about the parvoviruses circulating in Australian birds, including yellow canaries. Here, we present four parvoviral sequences including three novel parvoviruses detected from 10 yellow canaries (Crithagra flaviventris), named canary chaphamaparvovirus 1 and -2 (CaChPV1 and CaChPV2), canary dependoparvovirus 1 and -2 (CaDePV1 and CaDePV2). The whole genome sequences of CaChPV1, CaChPV2, CaDePV1, and CaDePV2 showed the highest identity with other parvoviruses at 76.4%, 75.9%, 84.0%, and 59.1%, respectively. Phylogenetic analysis demonstrated that CaChPV1 and CaChPV2 were clustered within the genus Chaphamaparvovirus. Meanwhile, CaDePV1 and CaDePV2 fall within the genus Dependoparvovirus and have the closest evolutionary relationship to the bird-associated dependoparvoviruses. Overall, this study enriched our understanding of the genetic diversity among avian parvoviruses within the Parvoviridae family.

Global distribution, cross-species transmission, and receptor binding of canine parvovirus-2: Risks and implications for humans.

For canine parvovirus -2 (CPV-2), a zoonotic virus capable of cross-species transmission in animals, the amino acid changes of capsid protein VP2 are key factors when binding to other species' transferrin receptors (TfR). CPV-2 variants can spread from felines and canines, for example, to Carnivora, Artiodactyla, and Pholidota species, and CPV-2c variants are essential to spread from Carnivora to Artiodactyla and Pholidota species in particular. In our study, a CPV-2a variant maintained a relatively stable trend, and the proportion of CPV-2c gradually rose from 1980 to 2021. The VP2 amino acid sequence analysis showed that five amino acid mutations at 426E/D, 305H/D, and 297S may be necessary for the virus to bind to different host receptors. Meanwhile, receptor-binding loop regions and amino acid sites 87 L, 93 N, 232I, and 305Y were associated with CPV-2 cross-species transmission. The homology of TfRs in different hosts infected with CPV-2 ranged from 77.2 % to 99.0 %, and from pig to feline, canine, and humans was 80.7 %, 80.4 %, and 77.2 %, respectively. The amino acid residues of TfRs involved in the viral binding in those hosts are highly conserved, which suggests that CPV-2 may be capable of pig-to-human transmission. Our analysis of the origin, evolutionary trend, cross-species transmission dynamics, and genetic characteristics of CPV-2 when binding to host receptors provides a theoretical basis for further research on CPV-2's mechanism of cross-species transmission and for establishing an early warning and monitoring mechanism for the possible threat of CPV-2 to animal-human public security.

Detection and genetic characterization of circulating canine parvovirus from stray dogs in Shanghai, China.

Canine parvovirus (CPV) is the main cause of viral diarrhea in dogs. CPV became a global disease in 1978 and was endemic all over the world. CPV-2 was the first strain to be identified, but with genetic mutations, new genotypes such as CPV-2a/2b/2c/new-2a/new-2b have emerged. In this study, 128 fecal samples of stray dogs suspected of CPV-2 infection were collected from January to March 2021 in Shanghai, China. All samples were screened by PCR and further analyzed by VP2 gene. The positive rate of CPV-2 was 9.4% (12/128), of which 6 CPV-2 isolates were successfully isolated. Phylogenetic tree analysis showed that 4 isolates were CPV-2c genotype and 2 were new-CPV-2b genotype. VP-2 is a key protein that determines the antigenic properties, host range and receptor binding of cpv-2. The results of VP2 amino acid sequence analysis in this study showed that the CPV-2c isolated strain was the same as the previous strains reported in China, including F267Y, Y324I, Q370R and A5G mutations in addition to the typical N426E mutations. Similarly, in addition to the conventional N426D, S297A, F267Y and Y324I mutations, the new CPV-2b isolate also had a new mutation of T440A. This study further confirmed the prevalence of CPV-2c and new-CPV-2b in Shanghai, and also found a new mutation site of new-CPV-2c, which provided a theoretical basis for further enriching the epidemiological data of CPV-2 in Shanghai, as well as the development of vaccines and the prevention and control of the disease.

Development of a time-resolved fluorescence immunoassay kit for detecting canine coronavirus and parvovirus through double labeling.

OBJECTIVE: Canine enteric coronavirus (CCV) and canine parvovirus type 2 (CPV-2) are the main pathogens responsible for acute gastroenteritis in dogs, and both single and mixed infections are common. This study aimed to establish a double-labeling time-resolved fluorescence immunoassay (TRFIA) to test and distinguish CCV and CPV-2 diseases. METHODS: A sandwich double-labeling TRFIA method was established and optimized using europium(III) (Eu3+)/samarium(III) (Sm3+) chelates. CCV/CPV-2 antigens were first captured by the immobilized antibodies. Then, combined with Eu3+/Sm3+-labeled paired antibodies, the Eu3+/Sm3+ fluorescence values were detected after dissociation to calculate the CCV/CPV-2 ratios. The performance, clinical performance and methodology used for laboratory (sensitivity, specificity, accuracy and stability) testing were evaluated. RESULTS: A double-label TRFIA for CCV and CPV-2 detection was optimized and established. The sensitivity of this TRFIA kit was 0.51 ng/mL for CCV and 0.80 ng/mL for CPV-2, with high specificity for CCV and CPV-2. All the accuracy data were less than 10%, and the recovery ranged from 101.21 to 110.28%. The kits can be temporarily stored for 20 days at 4 °C and can be stored for 12 months at temperatures less than - 20 °C. Based on a methodology comparison of 137 clinically suspected patients, there was no statistically significant difference between the TRFIA kit and the PCR method. Additionally, for CCV detection, the clinical sensitivity was 95.74%, and the clinical specificity was 93.33%. For CPV-2 detection, the clinical sensitivity was 92.86%, and the clinical specificity was 96.97%. CONCLUSION: In this study, a double-label TRFIA kit was prepared for CCV and CPV-2 detection with high laboratory sensitivity, specificity, accuracy, stability, clinical sensitivity and specificity. This kit provides a new option for screening/distinguishing between CCV and CPV-2 and may help improve strategies to prevent and control animal infectious diseases in the future.

NS1-mediated enhancement of MVC transcription and replication promoted by KAT5/H4K12ac.

Histone modifications function in both cellular and viral gene expression. However, the roles of acetyltransferases and histone acetylation in parvoviral infection remain poorly understood. In the current study, we found the histone deacetylase (HDAC) inhibitor, trichostatin A (TSA), promoted the replication and transcription of parvovirus minute virus of canines (MVC). Notably, the expression of host acetyltransferases KAT5, GTF3C4, and KAT2A was increased in MVC infection, as well as H4 acetylation (H4K12ac). KAT5 is not only responsible for H4K12ac but also crucial for viral replication and transcription. The viral nonstructural protein NS1 interacted with KAT5 and enhanced its expression. Further study showed that Y44 in KAT5, which may be tyrosine-phosphorylated, is indispensable for NS1-mediated enhancement of KAT5 and efficient MVC replication. The data demonstrated that NS1 interacted with KAT5, which resulted in an enhanced H4K12ac level to promote viral replication and transcription, implying the epigenetic addition of H4K12ac in viral chromatin-like structure by KAT5 is vital for MVC replication.IMPORTANCEParvoviral genomes are chromatinized with host histones. Therefore, histone acetylation and related acetyltransferases are required for the virus to modify histones and open densely packed chromatin structures. This study illustrated that histone acetylation status is important for MVC replication and transcription and revealed a novel mechanism that the viral nonstructural protein NS1 hijacks the host acetyltransferase KAT5 to enhance histone acetylation of H4K12ac, which relies on a potential tyrosine phosphorylation site, Y44 in KAT5. Other parvoviruses share a similar genome organization and coding potential and may adapt a similar strategy for efficient viral replication and transcription.

Canine parvovirus type 2 (CPV-2) serological and molecular patterns in dogs with viral gastroenteritis from southern Brazil.

Canine Parvovirus type 2 (CPV-2) is a highly contagious virus that can cause severe systemic disease with gastroenteric symptoms in dogs, particularly in young puppies. Originating from the feline parvovirus in the late 1970s, it swiftly propagated globally, instigating a pandemic in dogs. Despite vaccination advancements, CPV-2 remains a substantial challenge for veterinary professionals and pet owners. This study aimed to contribute knowledge about the current situation of CPV-2 among dogs in southern Brazil. In this study, the sera of 125 dogs (mostly with gastroenteritis symptoms) were screened for antibodies against CPV-2 and their faeces for the virus itself. The results showed that 40% (50/125) of dogs were infected with CPV-2. Most animals (65.5%) had previously been exposed to CPV-2 (with serotitres equal or above 1:40), and only 37.6% had protective antibody titres equal or above 1:80. The findings have also demonstrated that vaccination against CPV-2 significantly reduced the risk of infection, with positive cases decreasing from 56.9% (unvaccinated) to 2.0% (fully vaccinated). Furthermore, the prevalence of CPV-2 decreased as dogs aged, with younger dogs and those with an incomplete or non-existent vaccination history at the highest risk of infection. In conclusion, this study provides valuable insight into the prevalence and risk factors associated with CPV-2 infection in dogs in southern Brazil, thereby providing valuable knowledge for the improvement of veterinary care and pet health.

Sensitivity of lateral flow technique for diagnosis of canine parvovirus.

In this study, we devised a nanogold lateral flow immunoassay (LFA-CPV antigen test) for detecting canine parvovirus (CPV) in living attenuated CPV vaccines. We conducted instrumental characterization of the prepared nanogold particles and the developed LFA-CPV antigen test was rigorously evaluated for its performance verification including limit of detection, sensitivity, specificity, selectivity and accuracy. The LFA-CPV antigen test demonstrated strong performance when assessed against qPCR using different batches of live attenuated CPV vaccines, indicated a sensitivity of 96.4%, specificity of 88.2%, and an overall accuracy of 95%. These results suggest that the developed LFA-CPV antigen test could serve as a viable alternative for evaluation live attenuated CPV vaccines, and provide it as a point of care test for CPV diagnosis, offering a potential substitute for traditional laboratory methods, particularly qPCR.

First detection and genetic characterization of canine bufavirus in domestic dogs, Thailand.

Canine bufavirus (CBuV) was reported in domestic dogs worldwide. We conducted a survey of canine bufavirus in domestic dogs in Thailand from September 2016 to October 2022. Rectal swab samples (n = 531) were collected from asymptomatic dogs and dogs with gastroenteritis signs. The samples were tested for CBuV using PCR with specific primers to the VP1/VP2 gene, and 9.42% (50/531) was CBuV positive. Our findings showed that CBuVs could be detected in both symptomatic and healthy dogs. The Thai CBuVs were found in dogs from different age groups, with a significant presence in those under 1 year (12.60%) and dogs aged 1-5 years (7.34%) (p < 0.05), suggesting a high prevalence of Thai CBuVs in dogs under 5 years of age. We performed complete genome sequencing (n = 15) and partial VP1/VP2 sequencing (n = 5) of Thai CBuVs. Genetic and phylogenetic analyses showed that whole genomes of Thai CBuVs were closely related to Chinese and Italian CBuVs, suggesting the possible origin of Thai CBuVs. The analysis of VP1 and VP2 genes in Thai CBuVs showed that 18 of them were placed in subgroup A, while only 2 belonged to subgroup B. This study is the first to report the detection and genetic characterization of CBuVs in domestic dogs in Thailand. Additionally, surveillance and genetic characterization of CBuVs in domestic animals should be further investigated on a larger scale to elucidate the dynamic, evolution, and distribution of CBuVs.

Genetic characterization of the parvovirus full-length VP2 gene in domestic cats in Brazil.

Feline parvovirus (FPV) and canine parvovirus (CPV) are over 98% identical in their DNA sequences, and the new variants of CPV (2a/2b/2c) have gained the ability to infect and replicate in cats. The aim of this study was to determine the genetic diversity in the VP2 gene of parvovirus strains circulating in domestic cats in Brazil during a 10-year period (2008-2017). For parvovirus screening, specific PCR was performed, and 25 (34.7%) of 72 cats tested positive. The PCR-positive samples were further subjected to full-length VP2 sequencing (1755 bp), and eight sequences (36%) were characterized as FPV, seven (28%) as CPV-2a and (32%) nine (36%) as CPV-2b. One sequence (RJ1085/11) showing typical CPV amino acid (aa) at residues 80 R, 93 N, 103 A, 232 I, and 323 N could not be characterized at this time. The sequences in this study displayed aa changes previously described for FPV (A14T, A91S, I101T, N564S, and A568G) from cats and CPV-2a/2b (S297N and Y324L) from dogs. However, the Y324L mutation has not yet been reported in any CPV-2a/2b strains from cats. Phylogenetic analysis supported the division of these sequences into two well-defined clades, clade 1 for FPV and clade 2 for CPV2a/2b. Unusually, the sequence RJ1085/11 was grouped separately. Two recombination breakpoints were detected by Bootscan and 3Seq methods implemented in the RDP4. This study is the first report of CPV-2a/2b in cats in Brazil. The detection of FPV strains with mutations characteristic of CPV indicates that Brazilian FPV strains have undergone genetic changes.

Clinical and inflammatory response to antiviral treatments in dogs with parvoviral enteritis.

BACKGROUND: Canine parvoviral enteritis (CPE) is a fatal disease worldwide. The treatment of CPE is based mainly on supportive and symptomatic treatment. Antiviral addition to the treatment may result in a higher survival. OBJECTIVES: This study evaluated the effects of antiviral treatments with a standardized treatment (ST) on the clinical and inflammatory response of dogs with naturally occurring CPE. METHODS: Twenty-eight dogs with CPE caused by canine parvovirus type 2 were divided randomly into treatment groups. The ST group received fluid, antibiotic, antiemetic, and deworming treatments. The antiviral treatment groups received the same ST with an additional antiviral drug, recombinant feline interferon omega (rFeIFN-ω), oseltamivir (OSEL) or famciclovir (FAM). RESULTS: Compared to the healthy control, the tumor necrosis factor-α, interleukin-1ß, interferon (IFN)-α, IFN-γ, haptoglobin, and C-reactive protein values were high (p < 0.05) on day zero. At presentation, mild lymphopenia, neutropenia, and a high neutrophil to lymphocyte (LYM) ratio (NLR) were also observed. Adding rFeIFN-ω to the ST produced the best improvement in the clinical score with a decreased NLR, while leucocytes remained low and inflammatory markers stayed high on day three. The survival rates of the groups were 85.7% in ST+IFN, 71.4% in ST+OSEL, 71.4% in ST+FAM, and 57.1% in ST groups on day seven. CONCLUSIONS: Antiviral drugs may be valuable in treating CPE to improve the clinical signs and survival. In addition, the decrease in NLR in favor of LYM may be an indicator of the early prognosis before the improvement of leukocytes, cytokines, and acute phase proteins in CPE.

Molecular Survey on Porcine Parvoviruses (PPV1-7) and Their Association with Major Pathogens in Reproductive Failure Outbreaks in Northern Italy.

Successful reproductive performance is key to farm competitiveness in the global marketplace. Porcine parvovirus 1 (PPV1) has been identified as a major cause of reproductive failure, and since 2001 new species of porcine parvoviruses, namely PPV2-7, have been identified, although their role is not yet fully understood yet. The present study aimed to investigate PPVs' presence in reproductive failure outbreaks occurring in 124 farms of northern Italy. Fetuses were collected from 338 sows between 2019 and 2021 and tested for PPVs by real-time PCR-based assays and for other viruses responsible for reproductive disease. At least one PPV species was detected in 59.7% (74/124) of the tested farms. In order, PPV1, PPV5, PPV6, PPV7 and PPV4 were the most frequently detected species, whereas fewer detections were registered for PPV2 and PPV3. Overall, the new PPV2-7 species were detected in 26.6% (90/338) of the cases, both alone or in co-infections: PCV-2 (7.1%, 24/338), PCV-3 (8.2%, 28/338), and PRRSV-1 (6.2%, 21/338) were frequently identified in association with PPVs. Single PPVs detections or co-infections with other agents commonly responsible for reproductive failure should encourage future studies investigating their biological, clinical, and epidemiological role, for a better preparedness for potential emerging challenges in intensive pig production.

Early administration of canine parvovirus monoclonal antibody prevented mortality after experimental challenge.

OBJECTIVE: To evaluate the effectiveness of canine parvovirus monoclonal antibody (CPMA) as a treatment against canine parvovirus (CPV-2)-induced mortality and to support USDA product licensure. ANIMALS: 28 purpose-bred Beagle dogs aged 8 weeks were randomized to the treated (n = 21) or control (7) group. METHODS: Dogs were challenged intranasally with 104.2 TCID50 virulent CPV-2b on Day 0 and monitored for 14 days for fecal viral shed and clinical disease. All dogs began shedding CPV-2 on Day 4 and were treated intravenously with a single dose of either CPMA (0.2 mL/kg) or saline (equal volume). No additional treatments were given to either group. Feces and sera were collected for quantitative analysis of fecal viral shed (hemagglutination) and antibody responses (hemagglutination inhibition and dot-blot ELISA), respectively. Dogs were monitored twice daily for parameters including lymphopenia, fever, vomiting, abnormal feces, inappetence, and lethargy. Humane endpoints triggered euthanasia by a veterinarian masked to treatment groups. The primary outcome variable was prevention of mortality as compared to controls. RESULTS: Mortality was prevented in all CPMA-treated dogs compared to 57% mortality in the control group (P = .0017, Fisher exact test). Canine parvovirus monoclonal antibody-treated dogs also experienced less severe and/or shorter durations of diarrhea, fever, vomiting, CPV-2 shedding in feces, and lymphopenia. Both groups showed similar immunoglobulin M responses as measured by semiquantitative analysis. CLINICAL RELEVANCE: Intravenous administration of CPMA can effectively improve clinical outcome when administered early in CPV-2 disease. Canine parvovirus monoclonal antibody treatment after proven infection does not interfere with adaptive immunity.

Development and application of a multiplex PCR method for the simultaneous detection of goose parvovirus, waterfowl reovirus, and goose astrovirus in Muscovy ducks.

A multiplex polymerase chain reaction (PCR) method was developed to detect and distinguish goose parvovirus (GPV), waterfowl reovirus (WRV), and goose astrovirus (GAstV). Three pairs of primers were designed based on conserved regions in the genomic sequences of these enteric viruses and were used to specifically amplify targeted fragments of 493 bp from the viral protein 3 (VP3) gene of GPV, 300 bp from the sigma A-encoding gene of WRV, and 156 bp from the capsid protein-encoding gene of GAstV. The results showed that the primers can specifically amplify target fragments, without any cross-amplification with other viruses, indicating that the method had good specificity. A sensitivity test showed that the detection limit of the multiplex PCR method was 1 × 103 viral copies. A total of 102 field samples from Muscovy ducks with clinically suspected diseases were evaluated using the newly developed multiplex PCR method. The ratio of positive samples to total samples for GPV, WRV, and GAstV was 73.53% (75/102) for multiplex PCR and was 73.53% (75/102) for routine PCR. Seventy-five positive samples were detected by both methods, for a coincidence ratio of 100%. This multiplex PCR method can simultaneously detect GPV, WRV, and GAstV, which are associated with viral enteritis, thereby providing a specific, sensitive, efficient, and accurate new tool for clinical diagnosis and laboratory epidemiological investigations.