Research

Jump to: Other

13 pages, 1304 KiB

Open AccessArticle

Eradication of PRRS from Hungarian Pig Herds between 2014 and 2022

by István Szabó, Imre Nemes, Lajos Bognár, Zsolt Terjék, Tamás Molnár, Tamás Abonyi, Ádám Bálint, Dávid G. Horváth and Gyula Balka

Animals 2023, 13(24), 3747; https://doi.org/10.3390/ani13243747 - 05 Dec 2023

Viewed by 889

Abstract

Porcine reproductive and respiratory syndrome (PRRS) is a widespread infectious disease that is currently a major cause of economic losses in pig production. In Hungary, a National PRRS Eradication Program has been introduced to attain a more efficient, economic, and competitive international market [...] Read more.

Porcine reproductive and respiratory syndrome (PRRS) is a widespread infectious disease that is currently a major cause of economic losses in pig production. In Hungary, a National PRRS Eradication Program has been introduced to attain a more efficient, economic, and competitive international market position. The program has been also approved by the EU, but the resulting legal obligations have imposed a burden on Hungarian producers to comply with EU competition rules. The implementation of the program has been carried out by the veterinary authorities with the consent of, continuous support from and monitoring conducted by organisations within the pig sector as well as a scientific committee. The PRRS eradication program in Hungary was based on a regional territorial principle and was compulsory for all pig holdings within the regions. In Hungary, large fattening farms operate as all-in/all-out or continuous flow systems. Large-scale breeding herds are predominantly farrow-to-finish types. Although its significance has decreased in recent decades, 20% of the Hungarian pig population is still kept on small (backyard) farms (<100 animals). All PRRSV-infected large-scale farms had to develop a unit-adapted eradication plan, including external and internal biosecurity measures, vaccinations, etc. It was crucial to render each fattening unit free of the disease, as fattening units play a significant role in spreading the virus within the country. The eradication efforts mainly implemented were depopulation–repopulation methods, but on some farms a testing and removal method has been used. As the eradication progressed over the years, the introduction of infected fattening pigs was restricted. Thanks to these measures, Hungarian large-scale fattening farms became PRRSV-free by the end of 2018. The PRRSV-free status of small-scale herds was achieved by the end of 2015 and was maintained between 2016 and 2021. By 31 December 2021, all breeding pigs in large-scale farms in Hungary were free of wild-type PRRS virus. By 31 March 2022, the total pig population of the country, including all backyard farms and fattening units, achieved PRRSV-free status. The future goal is to ensure and maintain the PRRSV-free status of Hungary via strict import regulations of live animals combined with the continuous and thorough screening of incoming and resident herds for the presence of the virus. Full article

(This article belongs to the Special Issue Prevalence and Diagnosis of Viral Diseases in Pig Production)

► Show Figures

Figure 1

13 pages, 4179 KiB

Open AccessArticle

Rapid Visual Detection of African Swine Fever Virus with a CRISPR/Cas12a Lateral Flow Strip Based on Structural Protein Gene D117L

by Desheng Zhang, Sen Jiang, Nengwen Xia, Youwen Zhang, Jiajia Zhang, Anjing Liu, Chenyang Zhang, Nanhua Chen, Francois Meurens, Wanglong Zheng and Jianzhong Zhu

Animals 2023, 13(23), 3712; https://doi.org/10.3390/ani13233712 - 30 Nov 2023

Cited by 2 | Viewed by 938

Abstract

African swine fever virus (ASFV) is a large double-stranded DNA virus that is highly infectious and seriously affects domestic pigs and wild boars. African swine fever (ASF) has caused huge economic losses to endemic countries and regions. At present, there is still a [...] Read more.

African swine fever virus (ASFV) is a large double-stranded DNA virus that is highly infectious and seriously affects domestic pigs and wild boars. African swine fever (ASF) has caused huge economic losses to endemic countries and regions. At present, there is still a lack of effective vaccines and therapeutics. Therefore, rapid and accurate detection is essential for the prevention and control of ASF. The portable DNA endonuclease (Cas12a)-mediated lateral flow strip detection method (Cas12a-LFS) combined with recombinant polymerase amplification (RPA) has been gradually recognized as effective for virus detection including ASFV. In this study, based on the ASFV structural protein p17 gene (D117L), an RPA-Cas12a-LFS detection method was established. The detection method exhibits a sensitivity of up to two gene copies and has no cross-reaction with nine other swine viruses. Thus, the method is highly sensitive and specific. In 68 clinical samples, the coincidence rate of the p17 strip was 100%, compared to the traditional quantitative PCR (qPCR). In conclusion, we have developed a simple, rapid, sensitive, and specific ASFV visual detection method and demonstrated the potential of on-site detection of ASFV. Full article

(This article belongs to the Special Issue Prevalence and Diagnosis of Viral Diseases in Pig Production)

► Show Figures

Figure 1

7 pages, 407 KiB

Open AccessCommunication

Seroprevalence of Viral Enzootic Diseases in Swine Backyard Farms in Serbia

by Vesna Milićević, Dimitrije Glišić, Zorana Zurovac Sapundžić, Bojan Milovanović, Jelena Maletić, Nemanja Jezdimirović and Branislav Kureljušić

Animals 2023, 13(21), 3409; https://doi.org/10.3390/ani13213409 - 03 Nov 2023

Viewed by 1021

Abstract

Contrary to pig farming in developed Western countries, in a large part of the world, pigs are still traditionally kept in small backyard farms, usually for family needs. Their main characteristics are low biosecurity, swill feeding, natural breeding and uncontrolled trade. Given the [...] Read more.

Contrary to pig farming in developed Western countries, in a large part of the world, pigs are still traditionally kept in small backyard farms, usually for family needs. Their main characteristics are low biosecurity, swill feeding, natural breeding and uncontrolled trade. Given the high number of backyard farms in Serbia and the risk they are thought to pose to intensive pig farming, the main aim of this study was to evaluate the prevalence of major viral diseases of swine among traditionally kept pigs in small holdings with low biosecurity. For this investigation, 222 serum samples from 69 backyard holdings were randomly selected and tested for antibodies to Porcine Reproductive and Respiratory Syndrome virus (PRRSV), Aujeszky’s disease virus (ADV), Porcine Parvovirus (PPV) and Swine influenza Virus (SIV) by enzyme-linked immunosorbent assay (ELISA). The herd-level seroprevalence of PRRS, Aujeszky’s disease and PPV was 2.9%, 27.5% and 37.7%, respectively. Swine influenza seroconversion was not confirmed in any of the tested holdings. Despite widely distributed PPV and AD in backyard farms in Serbia, almost 50% of them are still negative for all the tested diseases. The backyard farms must be monitored, and owners must be educated as their role in eradication programs and obtaining country-free status may be crucial. Full article

(This article belongs to the Special Issue Prevalence and Diagnosis of Viral Diseases in Pig Production)

► Show Figures

Figure 1

14 pages, 3037 KiB

Open AccessArticle

Deep Sequencing of Porcine Reproductive and Respiratory Syndrome Virus ORF7: A Promising Tool for Diagnostics and Epidemiologic Surveillance

by Szilvia Jakab, Krisztina Bali, Csongor Freytag, Anna Pataki, Enikő Fehér, Máté Halas, Ákos Jerzsele, István Szabó, Krisztina Szarka, Ádám Bálint and Krisztián Bányai

Animals 2023, 13(20), 3223; https://doi.org/10.3390/ani13203223 - 15 Oct 2023

Cited by 1 | Viewed by 960

Abstract

Porcine reproductive and respiratory syndrome virus (PRRSV) is a major concern worldwide. Control of PRRSV is a challenging task due to various factors, including the viral diversity and variability. In this study, we evaluated an amplicon library preparation protocol targeting the ORF7 region [...] Read more.

Porcine reproductive and respiratory syndrome virus (PRRSV) is a major concern worldwide. Control of PRRSV is a challenging task due to various factors, including the viral diversity and variability. In this study, we evaluated an amplicon library preparation protocol targeting the ORF7 region of both PRRSV species, Betaarterivirus suid 1 and Betaarterivirus suid 2. We designed tailed primers for a two-step PCR procedure that generates ORF7-specific amplicon libraries suitable for use on Illumina sequencers. We tested the method with serum samples containing common laboratory strains and with pooled serum samples (n = 15) collected from different pig farms during 2019–2021 in Hungary. Testing spiked serum samples showed that the newly designed method is highly sensitive and detects the viral RNA even at low copy numbers (corresponding to approx. Ct 35). The ORF7 sequences were easily assembled even from clinical samples. Two different sequence variants were identified in five samples, and the Porcilis MLV vaccine strain was identified as the minor variant in four samples. An in-depth analysis of the deep sequencing results revealed numerous polymorphic sites along the ORF7 gene in a total of eight samples, and some sites (positions 12, 165, 219, 225, 315, 345, and 351) were found to be common in several clinical specimens. We conclude that amplicon deep sequencing of a highly conserved region of the PRRSV genome could support both laboratory diagnosis and epidemiologic surveillance of the disease. Full article

(This article belongs to the Special Issue Prevalence and Diagnosis of Viral Diseases in Pig Production)

► Show Figures

Figure 1

13 pages, 3679 KiB

Open AccessArticle

Epidemiologic and Genomic Characterizations of Porcine Kobuviruses in Diarrheic and Healthy Pigs

by Yu Zang, Binghui Feng, Zitao Huang, Dashi Zhao, Wenhao Qi, Yuejia Qiu, Ming Qiu, Chen Li, Hong Lin, Wanglong Zheng, Jianzhong Zhu and Nanhua Chen

Animals 2023, 13(19), 3129; https://doi.org/10.3390/ani13193129 - 07 Oct 2023

Viewed by 791

Abstract

Porcine kobuvirus (PKV) is an enteric virus commonly detected in both diarrheic and healthy pigs. Little is known about the role of PKV in enteric diseases. In this study, an epidemiological investigation based on 324 intestinal samples collected from six provinces of China [...] Read more.

Porcine kobuvirus (PKV) is an enteric virus commonly detected in both diarrheic and healthy pigs. Little is known about the role of PKV in enteric diseases. In this study, an epidemiological investigation based on 324 intestinal samples collected from six provinces of China during the period of 2018 to 2022 was performed, and showed that PKV has an overall 65.43% (212/324) positive rate. Noticeably, 89.47% (17/19) of PKV and porcine epidemic diarrhea virus (PEDV) double-positive pigs were clinically diseased, while 91.71% (177/193) of PKV-positive but PEDV-negative pigs were clinically healthy, suggesting that PKV infection in itself is unlikely to cause enteric diseases. In addition, three PKV genomes were obtained from both diseased and healthy pigs. Phylogenetic analysis showed that Chinese PKV strains could be divided into three groups (SH-W-CHN-like, S-1-HUN-like and JXAT2015-like strains). All three obtained PKV genomes belong to SH-W-CHN-like strains and JSYZ1806-158 was detected as a recombinant virus. Furthermore, multiple comparisons showed that nucleotide similarities are clearly lower than amino acid similarities for PKV polyproteins. Selective pressure analysis indicated that Chinese PKV polyproteins are predominantly under negative selection. Overall, this study provided new insights into the prevalence and evolution of PKV in both diarrheic and healthy pigs in China. Full article

(This article belongs to the Special Issue Prevalence and Diagnosis of Viral Diseases in Pig Production)

► Show Figures

Figure 1

15 pages, 2145 KiB

Open AccessArticle

Triplex-Loop-Mediated Isothermal Amplification Combined with a Lateral Flow Immunoassay for the Simultaneous Detection of Three Pathogens of Porcine Viral Diarrhea Syndrome in Swine

by Yi Hong, Biao Ma, Jiali Li, Jiangbing Shuai, Xiaofeng Zhang, Hanyue Xu and Mingzhou Zhang

Animals 2023, 13(12), 1910; https://doi.org/10.3390/ani13121910 - 07 Jun 2023

Cited by 1 | Viewed by 1136

Abstract

Porcine epidemic diarrhea virus (PEDV), porcine bocavirus (PBoV), and porcine rotavirus (PoRV) are associated with porcine viral diarrhea. In this study, triplex loop-mediated isothermal amplification (LAMP) combined with a lateral flow dipstick (LFD) was established for the simultaneous detection of PEDV, PoRV, and [...] Read more.

Porcine epidemic diarrhea virus (PEDV), porcine bocavirus (PBoV), and porcine rotavirus (PoRV) are associated with porcine viral diarrhea. In this study, triplex loop-mediated isothermal amplification (LAMP) combined with a lateral flow dipstick (LFD) was established for the simultaneous detection of PEDV, PoRV, and PBoV. The PEDV-gp6, PoRV-vp6, and PBoV-vp1 genes were selected to design LAMP primers. The amplification could be carried out at 64 °C using a miniature metal bath within 30 min. The triplex LAMP–LFD assay exhibited no cross-reactions with other porcine pathogens. The limits of detection (LODs) of PEDV, PoRV, and PBoV were 2.40 × 10¹ copies/μL, 2.89 × 10¹ copies/μL, and 2.52 × 10¹ copies/μL, respectively. The consistency between rt-qPCR and the triplex LAMP–LFD was over 99% in field samples testing. In general, the triplex LAMP–LFD assay was suitable for the rapid and simultaneous detection of the three viruses in the field. Full article

(This article belongs to the Special Issue Prevalence and Diagnosis of Viral Diseases in Pig Production)

► Show Figures

Figure 1

12 pages, 3484 KiB

Open AccessArticle

Isolation and Characterization of Swinepox Virus from Outbreak in Russia

by Andrey Koltsov, Mikhail Sukher, Natalia Kholod, Sanzhi Namsrayn, Sodnom Tsybanov and Galina Koltsova

Animals 2023, 13(11), 1786; https://doi.org/10.3390/ani13111786 - 27 May 2023

Viewed by 1295

Abstract

Swinepox virus (SWPV) is the only member of the Suipoxvirus genus of the Poxviridae family and is an etiologic agent of a worldwide disease specific for domestic and wild pigs. SWPV outbreaks are sporadically recorded in different regions of Russia. In 2013, an [...] Read more.

Swinepox virus (SWPV) is the only member of the Suipoxvirus genus of the Poxviridae family and is an etiologic agent of a worldwide disease specific for domestic and wild pigs. SWPV outbreaks are sporadically recorded in different regions of Russia. In 2013, an outbreak of the disease causing skin lesions was registered on a pig farm in Russia. The presence of SWPV in the scab samples was assessed by in-house real-time PCR, reference PCR amplification, and nucleotide sequencing of the viral late transcription factor-3 (VLTF-3) gene and was then confirmed by virus isolation. Thus, the in-house real-time PCR proposed in this study could serve as a useful tool for the rapid specific detection of the swinepox virus. In the study, it has been demonstrated for the first time that nasal and oral swabs can be used for PCR diagnosis of the disease and for swinepox virus isolation. Phylogenetic analysis revealed that the isolated virus was closely related to SWPV isolates registered in Germany, USA, and Brazil, and slightly differed from the Indian isolates. During experimental infection of pigs, a low pathogenicity of the Russian isolate was observed. Our data provides the first report on the isolation and characterization of swinepox virus in Russia. Full article

(This article belongs to the Special Issue Prevalence and Diagnosis of Viral Diseases in Pig Production)

► Show Figures

Figure 1

13 pages, 3757 KiB

Open AccessArticle

Genomic Characterizations of Porcine Epidemic Diarrhea Viruses (PEDV) in Diarrheic Piglets and Clinically Healthy Adult Pigs from 2019 to 2022 in China

by Binghui Feng, Chen Li, Yuejia Qiu, Wenhao Qi, Ming Qiu, Jixiang Li, Hong Lin, Wanglong Zheng, Jianzhong Zhu and Nanhua Chen

Animals 2023, 13(9), 1562; https://doi.org/10.3390/ani13091562 - 06 May 2023

Cited by 3 | Viewed by 1725

Abstract

Porcine epidemic diarrhea virus (PEDV) is a major causative pathogen of diarrheic disease. In this study, the prevalence and evolution of PEDV was evaluated using intestinal samples collected from six provinces of China in 2019–2022. PEDV could not only be detected in diarrheic [...] Read more.

Porcine epidemic diarrhea virus (PEDV) is a major causative pathogen of diarrheic disease. In this study, the prevalence and evolution of PEDV was evaluated using intestinal samples collected from six provinces of China in 2019–2022. PEDV could not only be detected in diarrheic piglets but also in adult pigs without enteric diseases. The complete genomes of five temporal and geographical representative PEDV strains were determined. Genome-based phylogenetic analysis indicated that XJ1904-700 belongs to the G2-a subgroup, while the other strains are clustered within the S-INDEL subgroup. Recombination analyses supported that JSNJ2004-919 is an inter-subgroup recombinant from SD2014-like (G2-b), CHZ-2013-like (G2-b) and CV777-like (G1-b) isolates, while FJFZ2004-1017 is an intra-subgroup recombinant from XM1-2-like (S-INDEL) and LYG-2014-like (S-INDEL) isolates. Both JSNJ2004-919 and FJFZ2004-1017 were from adult pigs, providing evidence that adult pigs may also serve as the host of PEDV reservoirs for virus evolution. Overall, this study provides new insights into PEDV’s prevalence and evolution in both diseased piglets and clinically healthy adult pigs. Full article

(This article belongs to the Special Issue Prevalence and Diagnosis of Viral Diseases in Pig Production)

► Show Figures

Figure 1

Other

Jump to: Research

6 pages, 427 KiB

Open AccessBrief Report

Time Farms Stay Naïve for Porcine Reproductive and Respiratory Syndrome

by Mariana Kikuti, Catalina Picasso-Risso, Claudio Marcello Melini and Cesar A. Corzo

Animals 2023, 13(2), 310; https://doi.org/10.3390/ani13020310 - 16 Jan 2023

Cited by 2 | Viewed by 1994

Abstract

Background: Hesitation on eliminating Porcine Reproductive and Respiratory Syndrome virus (PRRSV) from breeding herds exists since it is difficult to predict how long the herd will remain virus-free. We aimed to estimate the time that breeding herds remained virus-free (naïve) after PRRSV elimination [...] Read more.

Background: Hesitation on eliminating Porcine Reproductive and Respiratory Syndrome virus (PRRSV) from breeding herds exists since it is difficult to predict how long the herd will remain virus-free. We aimed to estimate the time that breeding herds remained virus-free (naïve) after PRRSV elimination was achieved. Methods: Production systems voluntarily shared their breeding herds’ health status weekly between July 2009 and October 2021. PRRSV incidence rate and the total number of days a breeding herd remained virus-free were estimated. Results: A total of 221 (17%) herds reached the naïve status 273 times. The median time sites remained in this status was approximately two years. The overall PRRS incidence rate after sites achieved a naïve status was 23.43 PRRS outbreaks per 100 farm years. Conclusion: Estimates obtained here provide insights on how frequently and for how long sites remain naïve, which contribute to informing management practices for PRRS control. Full article

(This article belongs to the Special Issue Prevalence and Diagnosis of Viral Diseases in Pig Production)

► Show Figures

Figure 1

Journal Menu

Journal Browser

Prevalence and Diagnosis of Viral Diseases in Pig Production

Share This Special Issue

Special Issue Editors

Special Issue Information

Keywords

Published Papers (9 papers)

Research

Other

Further Information

Guidelines

MDPI Initiatives

Follow MDPI