Skip to main content
Download PDF

Field study on the suitability of oral fluid samples for monitoring of Lawsonia intracellularis and Brachyspira hyodysenteriae by multiplex qPCR under field conditions

Porcine Health Management volume 11, Article number: 2 (2025) Cite this article

Abstract

Background

Monitoring or surveillance of infectious diseases is crucial in terms of herd health management of livestock. Investigations of oral fluids have become an animal friendly routine strategy to monitor respiratory pathogens in pigs. Less is known about the suitability of oral fluids for the detection of enteric pathogens in swine. In the present study we evaluated the use of oral fluids to monitor B. hyodysenteriae and L. intracellularis compared to pooled fecal samples by multiplex qPCR in a pen-wise follow-up of fattening pigs. Therefore, we collected oral fluids at an age of 12, 16 and 20 weeks of life and compared them to pooled fecal samples collected from the same pens on two fattening farms.

Results

Cohen´s Kappa analysis revealed a substantial agreement between oral fluids and pooled fecal samples on pen level (Cohen´s Kappa: 0.745; p < 0.001). DNA-loads of L. intracellularis were tendentially higher (p = 0.053) in pooled fecal samples than in the corresponding OFs.

Conclusions

The present study shows that oral fluids are an appropriate tool to monitor B. hyodysenteriae and L. intracellularis on conventional fattening farms under field conditions. However, multiple pen testing should be conducted to increase the diagnostic performance and sensitivity.

Background

Oral fluids (OFs) display a user and animal friendly way to gain material for herd diagnostics, that can easily be collected due to the natural explorative behavior of swine [1]. It displays a mixture of different components including saliva, food particle, cell detritus, tracheal-nasal secretions, gastrointestinal reflux, and serum-derived compounds, reviewed by Henao-Diaz, et al. [2]. The large number of animals that can be addressed by OF sampling can, under certain circumstances, increase the diagnostic sensitivity for the detection of infectious pathogens on pen [3] or herd level [4]. OFs are most notably known for surveillance or monitoring purposes of respiratory pathogens [5,6,7]. Although OFs are not sufficient to gain an etiological diagnose in pigs, they are well suited to obtain a prognostic profiling in a certain herd [7]. Naturally, enteric pathogens as Lawsonia (L.) intracellularis and Brachyspira (B.) hyodysenteriae are not present within these components. Concerning the use of OFs for L. intracellularis diagnostics, Barrera-Zarate, et al. [8] were able to demonstrate that OFs can facilitate indirect detection of the infection, but published studies on the detection of nucleic acids of L. intracellularis or Brachyspira spp. in OFs are rare up to date. Nevertheless, oral infection seems to be the most relevant way of pathogen transmission of the aforementioned pathogens [9], indicating that they could also be detected by examination of OFs. Furthermore, OFs are often contaminated with feces or liquid manure [2], leading to the hypothesis that enteric pathogens or at least genome fragments should be present in OFs. That enteric pathogens can principally be detected in OFs was already shown by Schott, et al. [10] who evaluated OFs for the surveillance of food-borne pathogens in pig farms. The ease of gaining animal- and user-friendly sampling material for herd diagnostics increases the compliance of farmers concerning diagnostic measures. As OFs can be used for the detection of several pathogens that play a major role for the herd health, the addition of enteric pathogens as L. intracellularis or B. hyodysenteriae to an OF-screening increases the diagnostic panel for OFs and thus, delivers more relevant data within one single diagnostic approach. Thus, the objective of the present examination was to evaluate the agreement of pen-wise collected pooled fecal samples (PFS) in terms of L. intracellularis and B. hyodysenteriae DNA detection rate on two fattening farms in Germany.

Methods

The present study was conducted on two fattening farms in Southern Germany (farm A and farm B) with a known history of L. intracellularis infection. Additionally, the herd attending veterinarian of farm B reported about a recent clinical outbreak of B. hyodysenteriae before the start of the study.

In both farms the pigs were kept in accordance with the guidelines of the German Animal Welfare Ordinance [12]. Farm A was a conventional fattening farm with a total of 1340 fattening pigs managed in a barn-wise all-in all-out workflow and a maximum of 28 pigs / pen. This farm purchased pigs 12 weeks of age from one sow herd. Vaccination with an oral life vaccine against L. intracellularis was carried out until six-month prior the present examination. Thus, the examined batch of pigs was not vaccinated against L. intracellularis. Furthermore, the pigs on this farm were vaccinated against porcine circovirus 2 (PCV2) and Mesomycoplasma (M.) hyopneumoniae as suckling piglets. The pigs received liquid feed via a sensor controlled short trough. The pigs were housed on concrete slatted floors; water was available ad libitum via nipple drinkers.

Farm B was a conventional fattening farm with a total of 500 fattening pigs managed in a continuous workflow with a maximum of 20 pigs / pen. This farm received pigs from different sources. However, all pigs within the study batch were from the same farm, where they received an oral live vaccine against L. intracellularis at three weeks of age. Further vaccinations of the piglets included vaccination against PCV2 and M. hyopneumoniae. Feeding was dry feed based on farm own cereals. The pigs were housed on concrete slatted floors; water was available ad libitum via nipple drinkers. Due to clinical signs of diarrhea within the 16th week of age, the herd attending veterinarian decided to treat the animal of the enrolled batch for five consecutive days with Tiamulinhydrogen-fumarate (Denagard®, Elanco Animal Health Deutschland GmbH, Bad Homburg, 8.8 mg/kg BDW) via the drinking water. The treatment was applied to the pigs after the collection of the OFs at 16th week of age.

Sampling

A pre-screening for B. hyodysenteriae, and L. intacellularis was conducted prior to the start of the study (approximately four weeks in farm A and seven weeks in farm B) in animals of a preceding batch to confirm the infection status of the farms as reported by the herd attending veterinarian. Therefore, 3 freshly dropped feces were collected from 5 pens of growing-finishing pigs (approximately 17 weeks of age for farm A and 20 weeks of age for farm B) in the corresponding farms. Fecal samples from each pen were pooled (pooled fecal sample, PFS) and examined as described below. Within the subsequently conducted follow-up study one newly introduced fattening batch was included (farm A: 12 pens; farm B: 10 pens). The samples were collected at 12 weeks (directly after placement), 16 weeks and 20 weeks of age always in the same pens. From each pen one pool of freshly dropped feces of three pigs/pen was collected. If feces with a divergent consistency were present, they were sampled preferentially. Thus, in total 66 (farm A: 36; farm B 30) pooled fecal samples were available for the examinations.

OFs were collected at the same time and from the same pens as the PFS. For the collection of the OFs the Oral Fluid Sample Collection Accessory Kit (IDEXX® Laboratories Inc.) were used. The ropes were placed at pig´s shoulder height in a clean area with distance to nipple drinkers, feeding through and neighboring pigs to avoid contamination. The ropes remained in the pens for approximately 20 min. For each pen one rope was used. Subsequently, the OFs were wrung out in the provided sealable 5 ml collection container. For each cotton rope new disposable gloves were used. In total 66 OFs were collected and available for molecular biological examinations. To ensure all samples were examined within the same batch of PCR all samples (PFS and OFs) were stored frozen at −20 °C until further analysis. Time between sampling and freezing did not exceed two hours. Storage before PCR examinations was up to eight weeks. A simple feces scores (FS) was obtained for each pen at the time of sampling as following: 1: normal feces consistency in the sampled pen at time of sampling, 2: feces with soft consistency present in the sampled pen at time of sampling, 3: soupy consistency / diarrhea present in the sampled pen at time of sampling.

Molecular biological examinations

All OFs and PFS of the study and the pre-screening were analyzed by the same batch of a multiplex qPCR as published elsewhere [11].

Statistical analysis

Gained data was documented in Microsoft Excel as metric scale (DNA copies/g feces) and encoded in binary data (e.g., PCR positive/negative). Statistical calculations were performed with the software IBM SPSS Statistics version 28.0.1.0 for Microsoft® Windows. Qualitative and quantitative PCR results were displayed descriptively. Metric data (qPCR results) were tested for normal distribution by Kolmogorov–Smirnoff Test. As the quantitative results of the qPCR were not normally distributed, the Mann–Whitney U Test was used to verify the Null Hypothesis of an equal distribution of the qPCR results over the categories Material (OFs vs. PFS). Chi2-test was conducted to evaluate associations between the detection of one pathogen in dependency of the used sample material. Odds ratio was determined to estimate the chance of detection for each pathogen and material. The interrater reliability between the materials PFS and OF to assign a pen as positive for one of the pathogens was evaluated by Cohens Kappa and interpreted as described by Landis and Koch [13]. Level of significance was p ≤ 0.05.

Results

Prescreening results

Pooled fecal samples from farm A were positive for L. intracellularis DNA only, whereas the examination of the pooled fecal samples from farm B revealed L. intracellularis and B. hyodysenteriae positive fecal pools (Table 1).

Table 1 Quantitative PCR results (DNA copies/g feces) of the pre-screening performed on farm A and B (n.d.= not detected)
Full size table

Results of the main study

In total 45.5% and 10.6% of all OFs were positive for L. intracellularis and B. hyodysenteriae DNA by qPCR, respectively. Concerning PFS, 37.9% were positive for L. intracellularis and 10.6% for B. hyodysenteriae DNA. Three pens were positive for both pathogens (Fig. 1B and C; farm B). An overview on the PCR results on pen level based on OFs and PFS is present in Table 2.

Fig. 1
figure 1

A Farm A: Quantitative results of the qPCR for L. intracellularis in PFS or OFs for each pen at different time points of sampling. Different colors indicate different DNA-loads in the sample material (green: negative, brown: the darker, the higher the DNA loads; n.d. = not detected). PCR results represent DNA copies/g feces or /ml OF. B Farm B: Quantitative results of the qPCR for L. intracellularis in PFS or OFs for each pen at different time points of sampling. Different colors indicate different DNA-loads in the sample material (green: negative, brown: the darker, the higher the DNA loads; n.d. = not detected). PCR results represent DNA copies/g feces or /ml OF. C Farm B: Quantitative results of the qPCR for B. hyodysenteriae for each pen at different time points of sampling. Different colors indicate different DNA-loads in the sample material (green: negative, brown: the darker, the higher the DNA loads; n.d. = not detected). PCR results represent DNA copies/g feces or /ml OF

Full size image
Table 2 Qualitative qPCR results for L. intracellularis and B. hyodysenteriae on pen level for both farms and all times of sampling and p-values for Chi2-test results
Full size table

There was no significant effect of the used materials on the odds to detect one of the two pathogens by PCR on pen level, except in week 16 on farm A when significantly more OFs were L. intracellularis positive than PFS (OR: 15.40; 95% CI: 1.47 – 160.97; p = 0.027). A detailed descriptive presentation of the qualitative and quantitative examination results over the entire study-period for each pen and sample occasion is given in Fig. 1A–C (Fig. 1A: farm A; only L. intracellularis positive; Fig. 1B and C: farm B; L. intracellularis and B. hyodysenteriae positive).

Although DNA loads of L. intracellularis were numerically higher in PFS (mean: 1.22 × 106) than in OFs (mean: 6.70 × 104) this difference was not statistically significant (p = 0.053). Concerning B. hyodysenteriae no significant differences concerning the DNA-loads in PFS (mean: 9.55 × 104) and OFs (mean: 1.56 × 104) were detected. The results of the qPCR at the three different times of sampling are depicted in Fig. 2.

Fig. 2
figure 2

Boxplots of DNA copies/g feces or ml OF for L. intracellularis and B. hyodysenteriae in oral fluids (OFs) and pooled feces samples (PFS) over the entire study period of both study farms. Only PCR positive results included

Full size image

To evaluate the agreement of both sample types on pen level for L. intracellularis or B. hyodysenteriae we calculated the Cohen´s Kappa over the entire study period for both farms and for each single time point of sampling and farm. This calculation revealed a substantial agreement for the status “pen L. intracellularis positive” and a close to perfect agreement for the status for “pen B. hyodysenteriae positive” for the entire study period and each farm. However, the results of the Cohen´s Kappa under respect of the different time points of sampling revealed a high variability. The detailed results concerning the interrater reliability are presented in Table 3.

Table 3 Cohen´s Kappa for: “pen L. intracellularis positive” or “pen B. hyodysenteriae positive” under consideration of both farms, time of sampling and total (n.d.: not detected)
Full size table

Fecal scores

In farm A, the mean feces score over the entire study period (FS: 2.16) was significantly (p < 0.001) higher compared to farm B (FS: 1.5). Under respect of the farm and considering both pathogens (where applicable), no significant associations were present between the feces score per pen and the DNA loads in the samples. Moreover, the chance to detect L. intracellularis or B. hyodysenteriae was not significantly associated with the feces score in the corresponding pens. The feces scores per pen at all times of sampling of farm A and farm B are shown in Fig. 3.

Fig. 3
figure 3

Feces scores of farm A and farm B for each time of sampling per pen over the entire study period

Full size image

Discussion

The present study was conducted on two farms with a known history of L. intracellularis or B. hyodysenteriae infection. This status was confirmed by a diagnostic screening prior the start of the study. Farm A revealed a L. intracellularis and farm B a L. intracellularis and B. hyodysenteriae positive screening result. From that point of view, our study population seemed to be adequate concerning the objectives of the study referring to the beforementioned pathogens. However, due to the limited number of farms and sample size, our study has explorative character and large-scale studies are necessary to generalize the present findings.

Meanwhile qPCR is very well established, both as mono-PCR and as multiplex PCR for rapid analysis of Brachyspira spp. and L. intracellularis with increased sensitivity compared to normal PCR and the simultaneous possibility of quantifying the pathogens [11, 14,15,16,17]. The multiplex approach offers a good possibility to detect several pathogens synchronously during screenings and to reduce the diagnostic workload. For the investigation of intestinal pathogens or pathogens shed by feces, pooled fecal samples (PFS) provide accessible sample sources at any time. Particularly for PCR analyses, the freshness of the samples is of secondary importance, so that the animals do not have to be fixed for rectal sampling, which reduces stress in the sampled population. However, when detecting microbial nucleic acids by PCR, false negative results can always be a result of inhibitors present in the feces of the animals [18, 19]. This aspect can play an essential role e.g., for L. intracellularis [20] detection thus affecting the sensitivity of the procedure. However, this drawback could display an advantage for OFs, because inhibitors from the feces are only present in traces here. Moreover, the suitability of OFs to detect and monitor gastrointestinal pathogens would enable a broad overview on circulating pathogens on a farm, in an animal and user-friendly way, as the molecular biological evaluation of OFs can include a whole range of pathogens known to be easily monitored [2, 21]. Examples for testing for nucleic acids of pathogens involving the gastro-intestinal tract (at least partially) from OFs are porcine circovirus 2 (PCV2), PCV3, porcine delta coronavirus (PDCoV), and porcine epidemic diarrhea virus (PEDV) [2, 21,22,23]. OFs were also used to detect Yersinia enterocolitica and others culturally and serologically [10]. However, only limited number of studies are available that have detected antibodies against L. intracellularis using OFs [8, 24]. Additionally, only two studies investigated the presence of B. hyodysenteriae or L. intracellularis in OFs of pigs, respectively [25, 26]. Due to the rationale described above and the very limited number of similar studies available, the need to learn more about the efficiency of L. intracellularis and B. hyodysenteriae detection from OFs is obvious.

In both farms the animals showed different levels of diarrhea within the study period but the clinical score was not associated with the level of pathogen shedding. This finding might be explained by the pen based fecal score and the pooling of the samples. Especially in terms of OFs, pigs with or without diarrhea might have chewed on the ropes. However, the study design was probably not optimal to state on a correlation between clinical signs and the level of pathogen shedding. Moreover, we did not exclude other pathogens or analyzed food sources that might have been involved in the clinical picture. However, shedding of L. intracellularis did not exceed critical levels of 107 L. intracellularis per gram of feces, associated with reduced weight gain [27] or108–109/g of Brachyspira, associated with the acute phase of the disease [28]. Concerning the DNA loads in the two sample materials, only a numerical difference was observed. A large-scale examination on this topic as available for PCV2 [3] (OFs vs. serum samples) could allow an adjustment of DNA loads in PFS and OFs by a factor. However, more comparative studies are needed for sufficient accuracy. In this way, it should also be possible to identify critical values for the assessment of the respective pathogens in the existing clinical picture. However, the high agreement resulting from Cohen's kappa values indicates the possibility of simplifying the detectionof L. intracellularis and B. hyodysenteriae by using OFs. Under respect of the different times of sampling a variability of the interrater reliability for the two sample materials was observed concerning L. intracellularis particularly in farm A in week 16 when OFs was more often positive than PFS. The rationale for this observation might be among others the larger number of animals that can be reached by OFS-sampling compared to the pools of individual collected freshly dropped feces.

Conclusions

The results of the present study showed the principle proof of concept for using OFs to monitor B. hyodysenteriae or L. intracellularis in conventional fattening farms under field conditions. Thus, OFs based monitoring of pig herds can be expanded for these pathogens. However, multiple pen testing should be conducted to increase the diagnostic performance and sensitivity.

Availability of data and materials

The original contributions presented in the study are included in the article, further inquiries can be directed to the corresponding author/s after reasonable request.

References

  1. Kittawornrat A, Zimmerman JJ. Toward a better understanding of pig behavior and pig welfare. Anim Health Res Rev. 2011;12(1):25–32.

    Article  PubMed  Google Scholar 

  2. Henao-Diaz A, Giménez-Lirola L, Baum DH, Zimmerman J. Guidelines for oral fluid-based surveillance of viral pathogens in swine. Porcine Health Manag. 2020;6(1):28.

    Article  PubMed  PubMed Central  Google Scholar 

  3. Nielsen GB, Nielsen JP, Haugegaard J, Leth SC, Larsen LE, Kristensen CS, et al. Comparison of serum pools and oral fluid samples for detection of porcine circovirus type 2 by quantitative real-time PCR in finisher pigs. Porcine Health Manag. 2018;4:2.

    Article  PubMed  PubMed Central  Google Scholar 

  4. Kittawornrat A, Panyasing Y, Goodell C, Wang C, Gauger P, Harmon K, et al. Porcine reproductive and respiratory syndrome virus (PRRSV) surveillance using pre-weaning oral fluid samples detects circulation of wild-type PRRSV. Vet Microbiol. 2014;168(2–4):331–9.

    Article  PubMed  Google Scholar 

  5. Biernacka K, Karbowiak P, Wrobel P, Chareza T, Czopowicz M, Balka G, et al. Detection of porcine reproductive and respiratory syndrome virus (PRRSV) and influenza A virus (IAV) in oral fluid of pigs. Res Vet Sci. 2016;109:74–80.

    Article  PubMed  CAS  Google Scholar 

  6. Cheong Y, Oh C, Lee K, Cho KH. Survey of porcine respiratory disease complex-associated pathogens among commercial pig farms in Korea via oral fluid method. J Vet Sci. 2017;18(3):283–9.

    Article  PubMed  PubMed Central  Google Scholar 

  7. Hernandez-Garcia J, Robben N, Magnee D, Eley T, Dennis I, Kayes SM, et al. The use of oral fluids to monitor key pathogens in porcine respiratory disease complex. Porcine Health Manag. 2017;3:7.

    Article  PubMed  PubMed Central  Google Scholar 

  8. Barrera-Zarate JA, Andrade MR, Pereira CER, Vasconcellos A, Wagatsuma MM, Sato JPH, et al. Oral fluid for detection of exposure to Lawsonia intracellularis in naturally infected pigs. Vet J. 2019;244:34–6.

    Article  PubMed  CAS  Google Scholar 

  9. Jordan DM, Knittel JP, Schwartz KJ, Roof MB, Hoffman LJ. A Lawsonia intracellularis transmission study using a pure culture inoculated seeder-pig sentinel model. Vet Microbiol. 2004;104(1–2):83–90.

    Article  PubMed  Google Scholar 

  10. Schott F, Hoffmann K, Sarno E, Bangerter PD, Stephan R, Overesch G, et al. Evaluation of oral fluids for surveillance of foodborne and zoonotic pathogens in pig farms. J Vet Diagn Invest. 2021;33(4):655–63.

    Article  PubMed  PubMed Central  CAS  Google Scholar 

  11. Willems H, Reiner G. A multiplex real-time PCR for the simultaneous detection and quantitation of Brachyspira hyodysenteriae, Brachyspira pilosicoli and Lawsonia intracellularis in pig faeces. Berl Munch Tierarztl Wochenschr. 2010;123(5–6):205–9.

    PubMed  CAS  Google Scholar 

  12. Verordnung zum Schutz landwirtschaftlicher Nutztiere und anderer zur Erzeugung tierischer Produkte gehaltener Tiere bei ihrer Haltung (Tierschutz-Nutztierhaltungsverordnung—TierSchNutztV). (2024)

  13. Landis JR, Koch GG. The measurement of observer agreement for categorical data. Biometrics. 1977;33(1):159–74.

    Article  PubMed  CAS  Google Scholar 

  14. Reiner G, Hillen S, von Berg S, Kixmoller M, Willems H. Analysis of bacterial load and prevalence of mixed infections with Lawsonia intracellularis, Brachyspira hyodysenteriae and/or Brachyspira pilosicoli in German pigs with diarrhoea. Berl Munch Tierarztl Wochenschr. 2011;124(5–6):236–41.

    PubMed  Google Scholar 

  15. Song Y, Hampson DJ. Development of a multiplex qPCR for detection and quantitation of pathogenic intestinal spirochaetes in the faeces of pigs and chickens. Vet Microbiol. 2009;137(1–2):129–36.

    Article  PubMed  CAS  Google Scholar 

  16. Stahl M, Kokotovic B, Hjulsager CK, Breum SO, Angen O. The use of quantitative PCR for identification and quantification of Brachyspira pilosicoli, Lawsonia intracellularis and Escherichia coli fimbrial types F4 and F18 in pig feces. Vet Microbiol. 2011;151(3–4):307–14.

    Article  PubMed  CAS  Google Scholar 

  17. Zmudzki J, Szczotka A, Podgorska K, Nowak A, Grzesiak A, Dors A, et al. Application of real-time PCR for detection of Lawsonia intracellularis and Brachyspira hyodysenteriae in fecal samples from pigs. Pol J Vet Sci. 2012;15(2):267–73.

    Article  PubMed  CAS  Google Scholar 

  18. Wilde J, Eiden J, Yolken R. Removal of inhibitory substances from human fecal specimens for detection of group A rotaviruses by reverse transcriptase and polymerase chain reactions. J Clin Microbiol. 1990;28(6):1300–7.

    Article  PubMed  PubMed Central  CAS  Google Scholar 

  19. Uwatoko K, Sunairi M, Yamamoto A, Nakajima M, Yamaura K. Rapid and efficient method to eliminate substances inhibitory to the polymerase chain reaction from animal fecal samples. Vet Microbiol. 1996;52(1–2):73–9.

    Article  PubMed  CAS  Google Scholar 

  20. Jacobson M, Englund S, Ballagi-Pordány A. The use of a mimic to detect polymerase chain reaction–inhibitory factors in feces examined for the presence of Lawsonia intracellularis. J Vet Diagn Invest. 2003;15(3):268–73.

    Article  PubMed  Google Scholar 

  21. Bjustrom-Kraft J, Christopher-Hennings J, Daly R, Main R, Torrison J, Thurn M, et al. The use of oral fluid diagnostics in swine medicine. J Swine Health Prod. 2018;26(5):262–9.

    Article  Google Scholar 

  22. Plut J, Jamnikar-Ciglenecki U, Golinar-Oven I, Knific T, Stukelj M. A molecular survey and phylogenetic analysis of porcine circovirus type 3 using oral fluid, faeces and serum. BMC Vet Res. 2020;16(1):281.

    Article  PubMed  PubMed Central  Google Scholar 

  23. Armenta-Leyva B, Munguia-Ramirez B, Gimenez-Lirola LG, Lin X, Ye F, Zimmerman J. Critical evaluation of strategies to achieve direct real-time PCR detection of swine pathogens in oral fluids. J Vet Diagn Invest. 2023;35(5):521–7.

    Article  PubMed  PubMed Central  CAS  Google Scholar 

  24. Gabardo MP, Sato JPH, Resende TP, Otoni LV, Rezende LA, Daniel AG, et al. Use of oral fluids to detect anti Lawsonia intracellularis antibodies in experimentally infected pigs. Pesqui Vet Bras. 2021;40:970–6.

    Article  Google Scholar 

  25. Wilberts BL, Arruda PH, Kinyon JM, Frana TS, Wang C, Magstadt DR, et al. Investigation of the impact of increased dietary insoluble fiber through the feeding of distillers dried grains with solubles (DDGS) on the incidence and severity of Brachyspira-associated colitis in pigs. PLoS ONE. 2014;9(12):e114741.

    Article  PubMed  PubMed Central  Google Scholar 

  26. Campler M, Cheng T-Y, Angulo J, Van De Weyer L, Arruda AG. Detection of Lawsonia intracellularis by oral fluids and fecal samples in Canadian swine. J Swine Health Prod 2024;32(4):156–63. https://doiorg.publicaciones.saludcastillayleon.es/10.54846/jshap/1388

  27. Collins AM, Barchia IM. The critical threshold of Lawsonia intracellularis in pig faeces that causes reduced average daily weight gains in experimentally challenged pigs. Vet Microbiol. 2014;168(2–4):455–8.

    Article  PubMed  Google Scholar 

  28. Hampson DJ, Burrough ER. Swine Dysentery and Brachyspiral Colitis. In: Zimmerman JJKL, Ramirez A, Schwartz KJ, Stevenson GW, Zhang J, editors. Diseases of Swine. 11th ed. Hoboken, NJ 07030, USA: John Wiley & Sons, Inc.; 2019. p. 951–70.

    Chapter  Google Scholar 

Download references

Acknowledgements

We acknowledge the support of the farmers involved in this study

Funding

Open Access funding enabled and organized by Projekt DEAL.

Author information

Authors and Affiliations

  1. Clinic for Swine at the Centre for Clinical Veterinary Medicine, Ludwig-Maximilians-Universität München, 85764, Oberschleissheim, Germany

    Matthias Eddicks, Sigena Junker, Julia Stadler & Mathias Ritzmann

  2. Clinic for Swine of the Justus-Liebig-Universität Gießen, 85392, Gießen, Germany

    Gerald Reiner, Hermann Willems & Sabrina Becker

  3. Veterinary Practice Hagn, 84076, Pfeffenhausen, Germany

    Josefine Hagn

Authors
  1. Matthias Eddicks
    View author publications

    You can also search for this author inPubMed Google Scholar

  2. Gerald Reiner
    View author publications

    You can also search for this author inPubMed Google Scholar

  3. Sigena Junker
    View author publications

    You can also search for this author inPubMed Google Scholar

  4. Hermann Willems
    View author publications

    You can also search for this author inPubMed Google Scholar

  5. Sabrina Becker
    View author publications

    You can also search for this author inPubMed Google Scholar

  6. Julia Stadler
    View author publications

    You can also search for this author inPubMed Google Scholar

  7. Josefine Hagn
    View author publications

    You can also search for this author inPubMed Google Scholar

  8. Mathias Ritzmann
    View author publications

    You can also search for this author inPubMed Google Scholar

Contributions

Conceptualization, M.E. and G.R.; methodology, G.R., ME, H.W., JS.; validation, H.W., G.R. and M.E.; formal analysis, M.E., M.R. and S.J.; investigation, S.J.; resources, J.H., T.K., M.R. and H.W.; S.B.; data curation, M.E. and J.S.; writing—original draft preparation, M.E. and G.R.; writing—review and editing, S.B., J.S., J.H., T.K. M.R., S.B., S.J.; visualization, M.E., S.B; supervision, M.E., G.R., M.R.; project administration, ME. All authors have read and agreed to the published version of the manuscript.

Corresponding author

Correspondence to Matthias Eddicks.

Ethics declarations

Ethics approval and consent to participate

Ethical approval was waived as oral fluid sampling is not rated as animal testing by the appropriate authority (Az. 2532.Vet_03-18–43).

Consent for publication

Written informed consent was obtained from the owners of the animals.

Competing interests

The authors declare no conflicts of interest.

Additional information

Publisher's Note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Rights and permissions

Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated in a credit line to the data.

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Eddicks, M., Reiner, G., Junker, S. et al. Field study on the suitability of oral fluid samples for monitoring of Lawsonia intracellularis and Brachyspira hyodysenteriae by multiplex qPCR under field conditions. Porc Health Manag 11, 2 (2025). https://doiorg.publicaciones.saludcastillayleon.es/10.1186/s40813-024-00415-4

Download citation

  • Received:

  • Accepted:

  • Published:

  • DOI: https://doiorg.publicaciones.saludcastillayleon.es/10.1186/s40813-024-00415-4

Keywords

Porcine Health Management

ISSN: 2055-5660

Contact us