111 Common nutritional and infectious health challenges in nursery pigs

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.

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Quantification of Site Layout and Filter Characteristics on Primary Filter Airflow Reduction on Commercial Swine Sites in Iowa

AgriEngineering ◽

10.3390/agriengineering1020022 ◽

2019 ◽

Vol 1 (2) ◽

pp. 291-302

Author(s):

Benjamin Smith ◽

Steven Hoff ◽

Jay Harmon ◽

Daniel Andersen ◽

Jeffrey Zimmerman ◽

...

Keyword(s):

Influenza A ◽

Energy Use ◽

Reduction Rate ◽

Disease Outbreaks ◽

Respiratory Syndrome Virus ◽

Positive Pressure ◽

Row Crop ◽

Site Layout ◽

Crop Harvest ◽

The Impact

Fresh air intake filtration is used on commercial swine breeding-gestation-farrowing farms to reduce the frequency of airborne infectious agents. For swine producers, porcine reproductive and respiratory syndrome virus (PRRSV), influenza A virus and Mycoplasma hyopneumoniae are considered the most economically challenging airborne pathogens. Reduced frequency of disease outbreaks has been attributed to retrofitting existing systems with filtration. Economic analysis of operating costs includes energy use, maintenance and replacement of filters. Filter replacement, the largest operational cost, is dependent on filter lifespan. However, limited data is available on filter lifespan and the rate of airflow reduction during the high dust-loading periods typically encountered for filtered swine building ventilation systems. Therefore, the objectives of this study were (1) estimate the average primary filter airflow reduction per day, (2) identify the impact of factors related to site layout, filter characteristics and weather on airflow reduction rates of filters in positive-pressure ventilated buildings and (3) determine methods for reducing average primary filter airflow reduction rate per day during row-crop harvest season. Both filter brand and the installed orientation of the filter significantly (p = 0.0314, p = 0.0419, respectively) impacted airflow reduction rates. All site layout factors were significant (driveway side, p = 0.001; dormer orientation, p = 0.0001; and dormer configuration, p = 0.0001). The materials tested significantly reduced the airflow reduction rate during row-crop harvest. The information obtained in this study will aid producers when planning for filtration, highlight details relevant to the purchase and installation of filters, identify factors that affect filter lifespan and identify methods for improving filter lifespan.

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Management Practices, Farmers’ Knowledge of Diseased Fish, and Their Occurrence in Fish Farms in Nyeri County, Kenya

Veterinary Medicine International ◽

10.1155/2021/8896604 ◽

2021 ◽

Vol 2021 ◽

pp. 1-13

Author(s):

Isaac R. Mulei ◽

Paul G. Mbuthia ◽

Robert M. Waruiru ◽

Phillip N. Nyaga ◽

Stephen Mutoloki ◽

...

Keyword(s):

Rainbow Trout ◽

Fish Species ◽

Management Practices ◽

Clinical Signs ◽

Small Scale ◽

Poor Growth ◽

Fish Waste ◽

Fish Diseases ◽

Diseased Fish ◽

The Impact

In this study, fish farmers’ management practices, occurrence, and knowledge of fish diseases in Nyeri County, Kenya, were evaluated. Fish farming management practices for small-scale farmers in Kenya have numerous challenges which have led to disease occurrence and reduced production. Moreover, the impact and association of these challenges to farmers’ knowledge of fish diseases and their burden has not been fully studied. A semistructured questionnaire was used to capture farmers’ biodata, fish species farmed, and farmers’ management practices such as handling of nets, pond fertilization, and disposal of fish waste. Farmers’ knowledge of fish diseases was based on their ability to identify independent and dependent variable indicators. Independent variables included clinical signs, decreased feeding, bulging eyes, floating on water, abdominal swelling, bulging eyes, abnormal skin color, reduced growth, and abnormal swimming with fish death as were the dependent variable. A total of 208 farmers were interviewed and included those of tilapia (134), mixed tilapia and catfish (40), catfish (22), rainbow trout, and five dams under cooperative management. Tilapia was the most kept fish species (66.8%) followed by polyculture of tilapia and catfish (20%) and rainbow trout (2%). Most respondents were male (78.5%) over 51 years of age (50%). Fifty percent of the respondents had secondary school education. There was a significant association between deaths and sharing of nets in Kieni East subcounty ( p = 0.0049 , chi-square), while on-farm fish waste disposing appeared to cause higher deaths compared to burning of the waste although not statistically significant ( p = 0.13 ). Few respondents observed decreased feed uptake (<20%) and poor growth. Fifty-seven percent of farmers reported mortalities. Fish poor growth, floating in water, and management practices in subcounties had significant effect on fish deaths. The farmers had knowledge of signs of diseased fish, but there was paucity of knowing the specific causes of disease. Farmers need to be empowered on best aquaculture husbandry to avoid disease transmission and specific fish disease signs to enhance proper reporting of disease for subsequent mitigation measures.

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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 ◽

10.3390/v13112169 ◽

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.

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BioFire FilmArray Decreases Infection Control Isolation Times by 4 days in ICU, BMT and Respiratory Wards

Open Forum Infectious Diseases ◽

10.1093/ofid/ofx163.852 ◽

2017 ◽

Vol 4 (suppl_1) ◽

pp. S353-S353 ◽

Cited By ~ 1

Author(s):

Titus Wong ◽

Aleksandra Stefanovic ◽

Kerstin Locher ◽

Elizabeth Bryce ◽

Jennifer M Grant ◽

...

Keyword(s):

Infection Control ◽

Influenza A ◽

Respiratory Infections ◽

Tertiary Care ◽

Diagnostic Testing ◽

Cost Benefit ◽

Respiratory Pathogen ◽

Duration Of Infection ◽

The Impact ◽

Research Grant

Abstract Background Novel, rapid, syndromic testing of patients presenting with respiratory infections has the potential to improve patient access and care by decreasing time to diagnosis. BioFire FilmArray (BioFire Diagnostics, bioMerieux) is a cartridge-based, multiplex PCR platform capable of detecting 17 viral and 3 bacterial targets in one hour. This study assessed the impact of implementing this technology on the duration of infection control isolation. Methods A randomized control trial in a 900-bed tertiary-care academic hospital was conducted between December 2016 and January 2017. Fifty consecutive samples of patients with respiratory infections on our ICU, BMT and Respiratory wards to received either BioFire FilmArray Respiratory Panel (BF) diagnostic testing or our routine diagnostic testing (RO) consisting of an influenza A/B/RSV PCR (in-house) followed by Luminex NxTag Respiratory Pathogen Panel that was batched at a reference lab. Five patient charts with missing data were excluded from analysis. Statistical analysis was completed using RStudio Version 1.0.136 – © 2009–2016 RStudio, Inc. Results Patients randomized to the BF arm remained on respiratory isolation precautions on average (42.3 ± 72.9 hours) over 100 hours less than patients randomized to the routine arm (151.3 ± 151.8 hours) (95% CI: 35.6–184.4 hours, P = 0.0052). Conclusion Implementing the BioFire FilmArray Respiratory Panel decreased infection control isolation time by approximately 4 days compared with routine testing; further study is warranted to determine the impact of this technology on patient outcomes and cost benefit. Disclosures T. Wong, bioMerieux: Investigator, Research grant A. Stefanovic, bioMerieux: Investigator, Research grant E. Bryce, bioMerieux: Investigator, Research grant J. M. Grant, bioMerieux: Investigator, Research grant D. Roscoe, bioMerieux: Investigator, Research grant

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

Pesquisa Veterinária Brasileira ◽

10.1590/s0100-736x2012001100013 ◽

2012 ◽

Vol 32 (11) ◽

pp. 1148-1154 ◽

Cited By ~ 2

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.

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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 ◽

10.3390/v14010148 ◽

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.

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Estimating the Effect of Respiratory Disease on Production Performance in Farrow-to-Finish Pig Farms

10.21203/rs.3.rs-30441/v1 ◽

2020 ◽

Author(s):

Maria Rodrigues da Costa ◽

Albert Rovira ◽

Montserrat Torremorell ◽

Rose Mary Fitzgerald ◽

Josep Gasa ◽

...

Keyword(s):

Respiratory Disease ◽

Influenza A ◽

Average Daily Gain ◽

Disease Status ◽

Production Performance ◽

Respiratory Syndrome Virus ◽

Feed Conversion ◽

Pig Farms ◽

Pig Performance ◽

The Impact

Abstract Background Respiratory disease is one of the most important factors impacting pig production worldwide. However, the literature highlights the multitude of confounding factors complicating the clear attribution of growth impairment to respiratory disease, and the extrapolation of the effects of respiratory disease to a wider population has not been thoroughly researched. The objective of this study was to estimate the impact of respiratory disease on production performance in a subset of 56 Irish farrow-to-finish pig farms. Proxies for respiratory disease status such as serology for four major pathogens (influenza A virus, porcine reproductive and respiratory syndrome virus, Mycoplasma hyopneumoniae and Actinobacillus pleuropneumoniae ), slaughter checks (pleurisy, pneumonia, lung abscesses, pericarditis and liver milk spots) and vaccination information were used as predictors for production performance. Results The models to estimate production performance from serology, slaughter checks, and vaccination were able to explain the variability of weaner and finisher mortality by 26 and 20%, respectively, and average daily feed intake (ADFI), average daily gain (ADG) and age at slaughter by 47, 40 and 41%, respectively. Feed conversion ratio and sow performance were not explained by the studied predictors. Conclusions The models fitted, especially those for ADFI, ADG and age at slaughter, emphasize the usefulness of sourcing information at different levels to understand the impact of farm health status on pig performance, and highlight the impact of respiratory disease on production performance.

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Diagnostic investigation of porcine periweaning failure-to-thrive syndrome

Journal of Veterinary Diagnostic Investigation ◽

10.1177/1040638711425939 ◽

2011 ◽

Vol 24 (1) ◽

pp. 96-106 ◽

Cited By ~ 15

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.

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Impacts of Quarterly Sow Mass Vaccination with a Porcine Reproductive and Respiratory Syndrome Virus Type 1 (PRRSV-1) Modified Live Vaccine in Two Herds

Vaccines ◽

10.3390/vaccines9101057 ◽

2021 ◽

Vol 9 (10) ◽

pp. 1057

Author(s):

Kasper Pedersen ◽

Charlotte Sonne Kristensen ◽

Lise Kirstine Kvisgaard ◽

Lars Erik Larsen

Keyword(s):

Negative Impact ◽

Mass Vaccination ◽

Respiratory Syndrome Virus ◽

Nursery Pigs ◽

Prrs Virus ◽

Before And After ◽

Strain Virus ◽

Modified Live Vaccine ◽

Paired Design ◽

The Impact

In recent years, there has been a considerable increase in the use of Modified Live PRRSV Vaccines (MLV) for mass vaccination in Denmark. The potential risks and negative impact of this strategy have been sparsely studied. The aim of this study was to investigate the impact of quarterly sow mass vaccination in two Danish sow herds. The study was performed as an observational prospective cohort of 120 sows in each of two commercial breeding herds in a paired design. Blood samples were taken from sows and oral fluid samples from nursery pigs (four to ten weeks old) before and after vaccination. The presence of PRRSV-1 RNA was measured by real time quantitative reverse transcription-polymerase chain reaction (RT-qPCR), and the level of PRRSV-1 specific antibodies was measured by two different serological assays. PRRS virus was not detected in the sow herds two days before and two weeks after vaccination, but the vaccine strain virus was detected in the nursery pigs. The prevalence of sows without antibodies towards PRRSV-1 went from 6–15% before vaccination to 1–4% after vaccination depending on the serological assay used, despite the fact that they had previously been repeatedly vaccinated. Four sows tested negative for antibodies in both assays after vaccination.

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Antibody responses to porcine reproductive and respiratory syndrome virus, influenza A virus, and Mycoplasma hyopneumoniae from weaning to the end of the finisher stage in fourteen groups of pigs in Ontario

10.21203/rs.2.22996/v1 ◽

2020 ◽

Author(s):

Elana Raaphorst ◽

Abdolvahab Farzan ◽

Robert M. Friendship ◽

Brandon N. Lillie

Keyword(s):

Influenza A Virus ◽

Influenza A ◽

Control Strategies ◽

Serum Antibody ◽

Swine Influenza ◽

Mycoplasma Hyopneumoniae ◽

Antibody Responses ◽

Respiratory Syndrome Virus ◽

Swine Farms ◽

The Impact

Abstract Background Porcine reproductive and respiratory syndrome, swine influenza, and mycoplasmal pneumonia are some of the most prevalent respiratory diseases affecting swine farm productivity in Canada. Monitoring for the prevalence of the infectious agents associated with these diseases on farm may help to improve herd-specific control strategies and to minimize the impact of disease on commercial swine farms. The objectives of this study were to investigate antibody responses to porcine reproductive and respiratory syndrome virus (PRRSV), influenza A virus (IAV), and Mycoplasma hyopneumoniae ( M. hyopneumoniae ) from weaning to the end of the finisher stage on a subset of commercial swine farms in Ontario and to examine the effects of nursery diet on antibody responses. Results Serology found 8, 61, and 31% of pigs at weaning, 1, 31, and 22% at the end of nursery, 8, 38, and 18% at the end of grower, and 11, 48, and 25% at the end of the finisher stage tested seropositive for PRRSV, IAV, and M. hyopneumoniae, respectively. Of the groups tested for PRRSV, IAV, and M. hyopneumoniae, 3, 14, and 5 groups had > 20% of pigs that tested seropositive at least once over the course of production (“high seropositivity”). In general, seropositivity was more likely to be lower at the end of nursery compared to the other production stages for all three pathogens, and more likely to be higher for PRRSV and IAV at weaning, end of grower, and end of finisher. Pigs that were seropositive for PRRSV were more likely to be seropositive forM. hyopneumoniae (p < 0.001). Overall, pigs fed a low complexity diet during nursery were more likely to be seropositive for PRRSV (p < 0.001) and IAV (p = 0.04). Conclusions This study provides information regarding changes in serum antibody in pigs across different stages of production and highlights periods of vulnerability. Additionally, these findings may encourage further research into the effects of nursery diet complexity on disease susceptibility and immune response.

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