scholarly journals Diagnostic investigation of porcine periweaning failure-to-thrive syndrome

2011 ◽  
Vol 24 (1) ◽  
pp. 96-106 ◽  
Author(s):  
Yanyun Huang ◽  
Henry Gauvreau ◽  
John Harding
Keyword(s):  
Influenza A ◽  
Clinical Signs ◽  
Case Fatality ◽  
Failure To Thrive ◽  
Torque Teno Virus ◽  
Porcine Circovirus ◽  
Respiratory Syndrome Virus ◽  
Transmissible Gastroenteritis Virus ◽  
Swine Industry ◽  
Diagnostic Investigation

Porcine periweaning failure-to-thrive syndrome (PFTS), an increasingly recognized syndrome in the swine industry of North America, is characterized by the anorexia of nursery pigs noticeable within 1 week of weaning, and progressive loss of body condition and lethargy during the next 1–2 weeks. Morbidity caused by PFTS is moderate, but case fatality is high. The etiology of PFTS is presently unknown and may include infectious agent(s), noninfectious factors, or both. PFTS was identified in a high health status farm with good management in early 2007. A diagnostic investigation was undertaken to identify the pathological lesions of, and infectious agents associated with, pigs demonstrating typical clinical signs. Affected (PFTS-SICK) and unaffected (PFTS-HLTHY) pigs from an affected farm, and unaffected pigs from 2 unaffected farms, were examined. The most prevalent lesions in PFTS-SICK pigs were superficial lymphocytic fundic gastritis, atrophic enteritis, superficial colitis, lymphocytic and neutrophilic rhinitis, mild nonsuppurative meningoencephalitis, and thymic atrophy. Rotavirus A and Betacoronavirus 1 (Porcine hemagglutinating encephalomyelitis virus) were identified only in PFTS-SICK pigs, but the significance of the viruses is uncertain because PFTS is not consistent with the typical presentation following infection by these pathogens. Porcine reproductive and respiratory syndrome virus, Porcine circovirus-2, Influenza A virus, Alphacoronavirus 1 (Transmissible gastroenteritis virus), Torque teno virus 1, Brachyspira hyodysenteriae, and Brachyspira pilosicoli were not identified in PFTS-SICK pigs. Suid herpesvirus 2 (Porcine cytomegalovirus), Porcine enteric calicivirus, Torque teno virus 2, pathogenic Escherichia coli, and coccidia were detected in both PFTS-SICK and PFTS-HLTHY pigs. It was concluded that there is a lack of compelling evidence that PFTS is caused by any of these pathogens.

scholarly journals Comparison of the Transcriptome Response within the Swine Tracheobronchial Lymphnode Following Infection with PRRSV, PCV-2 or IAV-S.

Pathogens ◽  
2020 ◽  
Vol 9 (2) ◽  
pp. 99 ◽  
Author(s):  
Miller ◽  
Fleming ◽  
Lager
Keyword(s):  
Gene Expression ◽  
Influenza A ◽  
Respiratory Infections ◽  
Statistical Tests ◽  
Respiratory Pathogen ◽  
Porcine Circovirus ◽  
Respiratory Syndrome Virus ◽  
Swine Industry ◽  
Viral Respiratory Infections ◽  
Viral Respiratory

Porcine reproductive and respiratory syndrome virus (PRRSV) is a major respiratory pathogen of swine that has become extremely costly to the swine industry worldwide, often causing losses in production and animal life due to their ease of spread. However, the intracellular changes that occur in pigs following viral respiratory infections are still scantily understood for PRRSV, as well as other viral respiratory infections. The aim of this study was to acquire a better understanding of the PRRS disease by comparing gene expression changes that occur in tracheobronchial lymph nodes (TBLN) of pigs infected with either porcine reproductive and respiratory syndrome virus (PRRSV), porcine circovirus type 2 (PCV-2), or swine influenza A virus (IAV-S) infections. The study identified and compared gene expression changes in the TBLN of 80 pigs following infection by PRRSV, PCV-2, IAV-S, or sham inoculation. Total RNA was pooled for each group and time-point (1, 3, 6, and 14 dpi) to make 16 libraries—analyses are by Digital Gene Expression Tag Profiling (DGETP). The data underwent standard filtering to generate a list of sequence tag raw counts that were then analyzed using multidimensional and differential expression statistical tests. The results showed that PRRSV, IAV-S and PCV-2 viral infections followed a clinical course in the pigs typical of experimental infection of young pigs with these viruses. Gene expression results echoed this course, as well as uncovered genes related to intersecting and unique host immune responses to the three viruses. By testing and observing the host response to other respiratory viruses, our study has elucidated similarities and differences that can assist in the development of vaccines and therapeutics that shorten or prevent a chronic PRRSV infection.

scholarly journals Porcine Gammaherpesviruses in Italian Commercial Swine Population: Frequent but Harmless

Pathogens ◽  
2021 ◽  
Vol 10 (1) ◽  
pp. 47
Author(s):  
Giovanni Franzo ◽  
Michele Drigo ◽  
Matteo Legnardi ◽  
Laura Grassi ◽  
Maria Luisa Menandro ◽  
...  
Keyword(s):  
Real Time ◽  
Real Time Pcr ◽  
Clinical Signs ◽  
Northern Italy ◽  
Porcine Circovirus ◽  
Swine Industry ◽  
Positive Interaction ◽  
High Prevalence ◽  
Swine Population ◽  
Clinical Conditions

Differently from alpha- and betaherpesviruses affecting swine, interest in the recently discovered Suid gammaherpesvirus 3, Suid gammaherpesvirus 4, and Suid gammaherpesvirus 5, also known as porcine lymphotropic herpesviruses (PLHV-1, PLHV-2, and PLHV-3), has largely focused on their role as potential zoonotic agents in cases of xenotransplantation. However, their role as primary pathogens of swine or as co-factors for other lymphotropic infections has essentially been neglected. The present study aims at filling this gap, evaluating the association between PLHVs infection and different clinical conditions and/or porcine circovirus (PCV) co-infection. One hundred seventy-six samples were obtained from different animals located in a high-density pig area of Northern Italy in the period 2017–2020. The presence of PLHVs and PCVs was tested and quantified by specific real-time PCR: PLHVs were widespread among pigs (PLHV-1, PLHV-2, and PLHV-3 prevalence was 28.97%, 10.79%, and 4.54%, respectively) and detected in all considered tissues and clinical conditions. Frequent co-infections were also observed among PLHVs and with PCVs, although a significant association was not detected with the exception of a positive interaction between PLHV-1 and PLHV-3, and a negative one between PLHV-2 and PCV-2. Significantly, no association between PLHVs, alone or in co-infection, emerged with any of the considered clinical signs, their frequency being comparable between healthy and diseased animals. Based on these pieces of evidence and despite their high prevalence, PLHVs’ relevance for the swine industry appears negligible, either as primary pathogens or as predisposing factors for circovirus-induced diseases.

scholarly journals Successive Inoculations of Pigs with Porcine Reproductive and Respiratory Syndrome Virus 1 (PRRSV-1) and Swine H1N2 Influenza Virus Suggest a Mutual Interference between the Two Viral Infections

Viruses ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 2169
Author(s):  
Juliette Bougon ◽  
Céline Deblanc ◽  
Patricia Renson ◽  
Stéphane Quéguiner ◽  
Stéphane Gorin ◽  
...  
Keyword(s):  
Influenza A ◽  
Viral Infections ◽  
Clinical Signs ◽  
Swine Influenza ◽  
Time Correlation ◽  
Respiratory Syndrome Virus ◽  
Cell Mediated Immune Response ◽  
Specific Pathogen ◽  
Porcine Respiratory

Porcine reproductive and respiratory syndrome virus (PRRSV) and swine influenza A virus (swIAV) are major pathogens of the porcine respiratory disease complex, but little is known on their interaction in super-infected pigs. In this study, we investigated clinical, virological and immunological outcomes of successive infections with PRRSV-1 and H1N2 swIAV. Twenty-four specific pathogen-free piglets were distributed into four groups and inoculated either with PRRSV at study day (SD) 0, or with swIAV at SD8, or with PRRSV and swIAV one week apart at SD0 and SD8, respectively, or mock-inoculated. In PRRSV/swIAV group, the clinical signs usually observed after swIAV infection were attenuated while higher levels of anti-swIAV antibodies were measured in lungs. Concurrently, PRRSV multiplication in lungs was significantly affected by swIAV infection, whereas the cell-mediated immune response specific to PRRSV was detected earlier in blood, as compared to PRRSV group. Moreover, levels of interferon (IFN)-α measured from SD9 in the blood of super-infected pigs were lower than those measured in the swIAV group, but higher than in the PRRSV group at the same time. Correlation analyses suggested an important role of IFN-α in the two-way interference highlighted between both viral infections.

scholarly journals 111 Common nutritional and infectious health challenges in nursery pigs

2019 ◽  
Vol 97 (Supplement_2) ◽  
pp. 62-63
Author(s):  
Eric R Burrough ◽  
Nicholas K Gabler
Keyword(s):  
Influenza A ◽  
Diagnostic Testing ◽  
Clinical Signs ◽  
Enterotoxigenic Escherichia Coli ◽  
Detection Methods ◽  
Respiratory Syndrome Virus ◽  
Common Source ◽  
Poor Growth ◽  
Nursery Pigs ◽  
The Impact

Abstract Poor starting nursery pigs are a common source of frustration for pork producers due to suboptimal lean tissue production and failure to thrive. This is generally a multifactorial issue with potential nutritional, infectious and management contributors. Commonly encountered respiratory and enteric pathogens include porcine reproductive and respiratory syndrome virus (PRRSV), influenza A virus (IAV), porcine enteric coronaviruses (TGEV/PEDV/PDCV), and group A, B, and C rotaviruses, as well as Salmonella typhimurium, enterotoxigenic Escherichia coli, Streptococcus suis, and Haemophilus parasuis. Infection with one or more of these agents can ultimately antagonize pig health and performance. However, while these specific pathogens may be causing an observed disease symptom, pigs may have been predisposed to infection due to various management, nutritional, and environmental risk factors. As many of these potential pathogens are endemic in production systems, it is important to remember that simply detecting a potential pathogen within a population is often not sufficient to assign cause for poor growth and production. To help fully interpret the impact of a detected agent, diagnostic efforts should focus on providing proof that the agent is actually causing disease. Molecular detection methods, such as PCR, are increasingly available for common pathogens and have high diagnostic sensitivity but lower diagnostic specificity. This paper will discuss the clinical signs and gross and microscopic lesions associated with common nursery pig pathogens, as well as proper sampling and diagnostic testing necessary to detect and confirm disease following infection with these agents.

scholarly journals Causes of swine polyserositis in a high-density breeding area in Italy

2020 ◽  
Vol 32 (4) ◽  
pp. 594-597
Author(s):  
Cristian Salogni ◽  
Massimiliano Lazzaro ◽  
Stefano Giovannini ◽  
Nicoletta Vitale ◽  
Maria Beatrice Boniotti ◽  
...  
Keyword(s):  
Influenza A ◽  
Pasteurella Multocida ◽  
Swine Influenza ◽  
High Density ◽  
Porcine Circovirus ◽  
Respiratory Syndrome Virus ◽  
Strong Positive Correlation ◽  
Breeding Area ◽  
Causative Agents ◽  
Bacterial Coinfection

We assessed the causes of polyserositis in pigs, categorized by causative agents and ages of animals affected. In a 3-y study, 246 pigs from 80 different farms with recurrent problems of polyserositis, in a high-density breeding area, were submitted for autopsy; 154 pigs with typical fibrinous serosal lesions were sampled for further bacterial and viral investigation. The most common gross lesions were pleuritis and pericarditis (141 of 154; 92%). The animals most affected were weaned pigs (139 of 154; 90%). Haemophilus parasuis and Mycoplasma hyorhinis were the most common bacteria detected and were present at the same rate (85 of 154; 55%). Other bacteria isolated were Streptococcus sp. (44 of 154; 29%), Pasteurella multocida (21 of 154; 14%), Escherichia coli (19 of 154; 12%), Actinobacillus pleuropneumoniae (7 of 154; 5%), and Trueperella pyogenes (4 of 154; 3%). Porcine reproductive and respiratory syndrome virus (PRRSV; 119 of 154; 77%) predominated among the viruses detected, followed, with lesser prevalence, by porcine circovirus 2 (40 of 154; 26%) and swine influenza A virus (19 of 154; 12%). Bacterial coinfection and coinfection of bacteria and viruses were common (128 of 154; 83%). A strong positive correlation was found between coinfection by H. parasuis and M. hyorhinis and also by H. parasuis with PRRSV.

scholarly journals Histopathological and immunohistochemical findings of swine with spontaneous influenza A infection in Brazil, 2009-2010

2012 ◽  
Vol 32 (11) ◽  
pp. 1148-1154 ◽  
Author(s):  
Tatiane T.N. Watanabe ◽  
Laura L. de Almeida ◽  
Flademir Wouters ◽  
Angelica T.B. Wouters ◽  
Priscila Zlotowski ◽  
...  
Keyword(s):  
Influenza A ◽  
Swine Influenza Virus ◽  
Clinical Signs ◽  
Swine Influenza ◽  
Rio Grande ◽  
Histological Evaluation ◽  
Respiratory Syndrome Virus ◽  
Rio Grande Do Sul ◽  
Herd Health ◽  
Mato Grosso

Swine influenza (SI) is caused by the type A swine influenza virus (SIV). It is a highly contagious disease with a rapid course and recovery. The major clinical signs and symptoms are cough, fever, anorexia and poor performance. The disease has been associated with other co-infections in many countries, but not in Brazil, where, however, the first outbreak has been reported in 2011. The main aim of this study was to characterize the histological features in association with the immunohistochemical (IHC) results for influenza A (IA), porcine circovirus type 2 (PCV2) and porcine reproductive and respiratory syndrome virus (PRRSV) in lung samples from 60 pigs submitted to Setor de Patologia Veterinária at the Universidade Federal do Rio Grande do Sul (SPV-UFRGS), Brazil, during 2009-2010. All of these lung samples had changes characterized by interstitial pneumonia with necrotizing bronchiolitis, never observed previously in the evaluation of swine lungs in our laboratory routine. Pigs in this study had showed clinical signs of a respiratory infection. Swine samples originated from Rio Grande do Sul 31 (52%), Santa Catarina 14 (23%), Paraná 11 (18%), and Mato Grosso do Sul 4 (7%). Positive anti-IA IHC labelling was observed in 45% of the cases, which were associated with necrotizing bronchiolitis, atelectasis, purulent bronchopneumonia and hyperemia. Moreover, type II pneumocyte hyperplasia, alveolar and bronchiolar polyp-like structures, bronchus-associated lymphoid tissue (BALT) hyperplasia and pleuritis were the significant features in negative anti-IA IHC, which were also associated with chronic lesions. There were only two cases with positive anti-PCV2 IHC and none to PRRSV. Therefore, SIV was the predominant infectious agent in the lung samples studied. The viral antigen is often absent due to the rapid progress of SI, which may explain the negative IHC results for IA (55%); therefore, IHC should be performed at the beginning of the disease. This study has shown how important a careful histological evaluation is for the diagnosis. Since 2009, a new histological feature of swine pneumonia in animals with respiratory clinical signs has been observed in samples from pigs with clinical respiratory disease submitted to SPV-UFRGS. In addition, the results proved the importance of histological evaluation for swine herd health management.

scholarly journals Detection of Porcine Respirovirus 1 (PRV1) in Poland: Incidence of Co-Infections with Influenza A Virus (IAV) and Porcine Reproductive and Respiratory Syndrome Virus (PRRSV) in Herds with a Respiratory Disease

Viruses ◽  
2022 ◽  
Vol 14 (1) ◽  
pp. 148
Author(s):  
Aleksandra Woźniak ◽  
Piotr Cybulski ◽  
Lilla Denes ◽  
Gyula Balka ◽  
Tomasz Stadejek
Keyword(s):  
Respiratory Disease ◽  
Influenza A ◽  
Clinical Signs ◽  
Virus Detection ◽  
Respiratory Syndrome Virus ◽  
Respiratory Problems ◽  
Oral Fluids ◽  
Nasal Swabs ◽  
Pig Health

Porcine respirovirus 1 (PRV1) is also known as porcine parainfluenza virus 1 (PPIV1). The prevalence and the role of PRV1 infections for pig health is largely unknown. In order to assess the PRV1 prevalence in Poland, nasal swabs and oral fluids collected from pigs from 30 farms were examined with RT real-time PCR. Additionally, IAV and PRRSV infection statuses of PRV1-positive samples were examined. The results showed that the virus is highly prevalent (76.7% farms positive) and different patterns of PRV1 circulation in herds with mild–moderate respiratory disease were observed. Co-infections with IAV and PRRSV were infrequent and detected in 8 (23.5%) and 4 (11.8%) out of 34 PRV1-positive nasal swab pools from diseased pens, respectively. In one pen PRV1, IAV, and PRRSV were detected at the same time. Interestingly, PRV1 mean Ct value in samples with co-infections was significantly lower (29.8 ± 3.1) than in samples with a single PRV1 infection (32.5 ± 3.6) (p < 0.05), which suggested higher virus replication in these populations. On the other hand, the virus detection in pig populations exhibiting respiratory clinical signs, negative for PRRSV and IAV, suggests that PRV1 should be involved in differential diagnosis of respiratory problems.

scholarly journals Association of Porcine Circovirus Type 2 With Vascular Lesions in Porcine Pneumonia

2011 ◽  
Vol 49 (2) ◽  
pp. 264-270 ◽  
Author(s):  
L. Szeredi ◽  
Á. Dán ◽  
N. Solymosi ◽  
A. Cságola ◽  
T. Tuboly
Keyword(s):  
Pasteurella Multocida ◽  
Swine Influenza Virus ◽  
Clinical Signs ◽  
Porcine Circovirus Type ◽  
Porcine Circovirus Type 2 ◽  
Vascular Lesions ◽  
Porcine Circovirus ◽  
Respiratory Syndrome Virus ◽  
Respiratory Pathogens

The aim of this study was to evaluate the vasculature in porcine circovirus type 2–infected (PCV2-infected) lungs and to identify the PCV2 subtypes involved in porcine pneumonia. Pulmonary samples from 140 pigs, 2 weeks to 7 months of age, from 36 Hungarian commercial herds with clinical signs of respiratory disease were examined for the presence of respiratory pathogens, with bacterial culture, pathologic evaluation, and immunohistochemistry for PCV2, porcine reproductive respiratory syndrome virus, and swine influenza virus. PCV2 was the most commonly identified pathogen (49 cases) among the 74 of 140 cases (53%) with respiratory pathogens. PCV2 was detected immunohistochemically in the wall of 13% to 100% of pulmonary vessels (mean, 89%) in 38 of 49 cases (78%). Detection of PCV2 antigen was positively correlated with the presence of vascular lesions ( P < .001, odds ratio [OR]: 159.54). Other pathogens capable of vascular injury in swine were found in 29 of 49 of the PCV2-positive cases (59%). The probability of detecting vascular lesions in PCV2-infected lung was higher than in infection with porcine reproductive respiratory syndrome virus ( P < .002, OR: 14.63), Pasteurella multocida infection ( P < .001, OR: 5.75), or Streptococcus spp. infection (not significant, OR: 1.45). Sequence analysis of open reading frame 2 amplicons was possible in 6 PCV2-positive cases, from which 5 cases proved to be PCV2b subtype and 1 case, PCV2a subtype. In conclusion, PCV2 antigen was commonly colocalized with pulmonary vascular lesions in pneumonia in Hungarian swine, and PCV2b was the dominant subtype.

scholarly journals Vaccination with a Porcine Reproductive and Respiratory Syndrome (PRRS) Modified Live Virus Vaccine Followed by Challenge with PRRS Virus and Porcine Circovirus Type 2 (PCV2) Protects against PRRS but Enhances PCV2 Replication and Pathogenesis Compared to Results for Nonvaccinated Cochallenged Controls

2015 ◽  
Vol 22 (12) ◽  
pp. 1244-1254 ◽  
Author(s):  
Megan C. Niederwerder ◽  
Bhupinder Bawa ◽  
Nick V. L. Serão ◽  
Benjamin R. Trible ◽  
Maureen A. Kerrigan ◽  
...  
Keyword(s):  
Average Daily Gain ◽  
Disease Model ◽  
Clinical Signs ◽  
Porcine Circovirus Type ◽  
Porcine Circovirus Type 2 ◽  
Porcine Circovirus ◽  
Respiratory Syndrome Virus ◽  
Live Virus ◽  
Pcv2 Replication

ABSTRACTCoinfections involving porcine reproductive and respiratory syndrome virus (PRRSV) and porcine circovirus type 2 (PCV2) contribute to a group of disease syndromes known as porcine circovirus-associated disease (PCVAD). Presumably, PRRSV infection enhances PCV2 replication as a result of modulation of host immunity. The purpose of this study was to evaluate PCV2 replication and pathogenesis in pigs vaccinated with a PRRS modified live virus (MLV) vaccine and subsequently challenged with a combination of PRRSV and PCV2. During the early postchallenge period, the number of pigs with PRRSV-associated clinical signs was decreased, and average daily gain (ADG) was increased, in the vaccinated group, demonstrating the protective effect of PRRS vaccination. However, during the later postchallenge period, more pigs in the vaccinated group showed increased PCV2 viremia, decreased ADG, increased PCVAD clinical signs, and increased mortality. In this disease model, the early benefits of PRRSV vaccination were outweighed by the later amplification of PCVAD.

scholarly journals Detection of agents associated with respiratory diseases of swine by real time PCR

2015 ◽  
Vol 16 (2) ◽  
pp. 300-307 ◽  
Author(s):  
Antônio Augusto FONSECA JUNIOR ◽  
Carolina Kymie Vasquez NONAKA ◽  
Estefânia de Oliveira GUEDES ◽  
Zélia Inês Portela LOBATO ◽  
Alessandra Silva DIAS ◽  
...  
Keyword(s):  
Real Time ◽  
Pseudorabies Virus ◽  
Clinical Signs ◽  
Infectious Agent ◽  
Porcine Circovirus ◽  
Infectious Agents ◽  
Swine Industry ◽  
Specific Infectious Agent ◽  
Pooled Samples ◽  
Porcine Respiratory

Porcine Respiratory Disease Complex (PRDC) is a group of diseases that cause high losses in the swine industry. Several infectious agents are related to PRDC including porcine circovirus 2 (PCV-2), pseudorabies virus (SuHV-1),Haemophilus parasuis (HP), Mycoplasma hypneumoniae (MH) and Pasteurela multocida (PM). The aim of this study was to develop real-time PCRs (qPCR) for the detection of these infectious agents. Oligonucleotides were designed for each specific infectious agent and labeled with different fluorophores to amplify specific parts of the genome. This was done in two groups of reactions—a duplex qPCR for SuHV-1 and PCV-2 and a multiplex qPCR to detect the three bacteria simultaneously. The reactions were tested in 142 pooled samples of swine lymph nodes and lungs with clinical signs of PRDC. There were 135 samples that tested positive for PCV-2, 61 for HP, 29 for PM, 30 for MH and zero for SuHV-1. We recorded 76 cases of co-infection. The qPCRs developed in this study are useful tools in the diagnosis of PRDC.

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