TY - JOUR

T1 - Evaluation of a novel multiplex qPCR method for rapid detection and quantification of pathogens associated with calf diarrhoea

AU - Pansri, Potjamas

AU - Svensmark, Birgitta

AU - Liu, Gang

AU - Thamsborg, Stig Milan

AU - Kudirkiene, Egle

AU - Nielsen, Henrik Vedel

AU - Goecke, Nicole Bakkegård

AU - Olsen, John Elmerdahl

N1 - Publisher Copyright: © 2022 The Authors. Journal of Applied Microbiology published by John Wiley & Sons Ltd on behalf of Society for Applied Microbiology.

PY - 2022

Y1 - 2022

N2 - Aims: Diarrhoea is a common health problem in calves and a main reason for use of antimicrobials. It is associated with several bacterial, viral and parasitic pathogens, most of which are commonly present in healthy animals. Methods, which quantify the causative agents, may therefore improve confidence in associating a pathogen to the disease. This study evaluated a novel commercially available, multiplex quantitative polymerase chain reaction (qPCR) assay (Enterit4Calves) for detection and quantification of pathogens associated with calf-diarrhoea. Methods and Results: Performance of the method was first evaluated under laboratory conditions. Then it was compared with current routine methods for detection of pathogens in faecal samples from 65 calves with diarrhoea and in 30 spiked faecal samples. The qPCR efficiencies were between 84%–103% and detection limits of 100–1000 copies of nucleic acids per sample were observed. Correct identification was obtained on 42 strains of cultured target bacteria, with only one false positive reaction from 135 nontarget bacteria. Kappa values for agreement between the novel assay and current routine methods varied between 0.38 and 0.83. Conclusion: The novel qPCR method showed good performance under laboratory conditions and a fair to good agreement with current routine methods when used for testing of field samples. Significance and impact of study: In addition to having fair to good detection abilities, the novel qPCR method allowed quantification of pathogens. In the future, use of quantification may improve diagnosis and hence treatment of calf diarrhoea.

AB - Aims: Diarrhoea is a common health problem in calves and a main reason for use of antimicrobials. It is associated with several bacterial, viral and parasitic pathogens, most of which are commonly present in healthy animals. Methods, which quantify the causative agents, may therefore improve confidence in associating a pathogen to the disease. This study evaluated a novel commercially available, multiplex quantitative polymerase chain reaction (qPCR) assay (Enterit4Calves) for detection and quantification of pathogens associated with calf-diarrhoea. Methods and Results: Performance of the method was first evaluated under laboratory conditions. Then it was compared with current routine methods for detection of pathogens in faecal samples from 65 calves with diarrhoea and in 30 spiked faecal samples. The qPCR efficiencies were between 84%–103% and detection limits of 100–1000 copies of nucleic acids per sample were observed. Correct identification was obtained on 42 strains of cultured target bacteria, with only one false positive reaction from 135 nontarget bacteria. Kappa values for agreement between the novel assay and current routine methods varied between 0.38 and 0.83. Conclusion: The novel qPCR method showed good performance under laboratory conditions and a fair to good agreement with current routine methods when used for testing of field samples. Significance and impact of study: In addition to having fair to good detection abilities, the novel qPCR method allowed quantification of pathogens. In the future, use of quantification may improve diagnosis and hence treatment of calf diarrhoea.

KW - Calf diarrhoea

KW - calf scours

KW - detection

KW - multiplex qPCR

KW - quantification

U2 - 10.1111/jam.15722

DO - 10.1111/jam.15722

M3 - Journal article

C2 - 35858716

AN - SCOPUS:85135184540

VL - 133

SP - 2516

EP - 2527

JO - Proceedings of the Society for Applied Bacteriology

JF - Proceedings of the Society for Applied Bacteriology

SN - 0266-8254

IS - 4

ER -