Allan, Kathryn

Halliday, Jo

Vazquez, Richard

Viora, Lorenzo

Weller, Griffin

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RESEARCH POSTER PRESENTATION DESIGN © 2019www.PosterPresentations.comCoxiella (C.) burnetii is an obligate intracellular, gram-negativebacterium and the etiologic agent of Q fever in humans and coxiellosisin animals. The relationship between coxiellosis and reproductivedisease in cattle, such as uterine infections, is slowly becoming betterunderstood (Muskens, Van Maanen and Mars, 2011). Previous studieshave linked C. burnetii infection to reproductive diseases in dairy cattlebreeds (Ullah et al. 2022). Coxiella burnetii has also been identified as apresumptive etiology of abortion in cattle by qPCR testing usingplacental tissues, vaginal swabs, and exterior foetal swabs (Thomas etal., 2022). The prevalence of this pathogen in UK dairy herds has beenfound to be 79.7% and 28.6% based on bulk tank milk ELISA andPCR tests, respectively (Velasova et al., 2017).Although C. burnetii is shed mainly via birth products (e.g., birth fluidsand placenta) in ruminants (Figure 1), it can also be shed via vaginalmucous, milk, faeces and semen (Guatteo et al., 2011). Hence, usingalternative samples aside from birth products can be viable fordiagnosing coxiellosis when placental or foetal tissues are not available.IntroductionStudy AimResultsDiscussion and ConclusionThe initial IS1111 qPCR results indicate that C. burnetii is endemic tothe farm habitat, with various Ct scores shown from individuals tested.The effect of parity in the qPCR results may be due to naïve heifershaving an initial exposure to C. burnetii after their introduction in theadult herd. The qPCR test found individuals with Ct’s ≤ 27 which canbe attributable to clinical disease. However, further analysis is requiredto determine impacts on production as well as correlate infection statusto reproductive dysfunction.References1. Agerholm, J., 2013. Coxiella burnetii associated reproductive disorders in domestic animals - a critical review. Acta Vet Scand 55:132. Guatteo, R., Seegers, H., Taurel, A.F., Joly, A. and Beaudeau, F., 2011. Prevalence of Coxiella burnetii infection in domestic ruminants: a critical review. Veterinary microbiology, 149(1-2), pp.1-16.3. Thomas, K., Kibona, T., Claxton, J.R., de Glanville, W.A., Lankester, F., Amani, N., Buza, J.J., Carter, Ryan., Chapman, G.E., Crump, J.A., Dagleish, M.P., Halliday, J.E.B., Hamilton, C.M., Innes, E.A., Katzer, F., Livingstone, M. Longbottom, D., Millins, C., Mmmbaga, B.T., Mosha, V., Nyarobi, J., Nyasebwa, O.M, Russell, G.C, Sanka, P.N., Semango, G., Wheelhouse, N., Willett, B.J., Cleveland, S., Allan, K.J., 2022. Prospective chort study reveals unexpected aetiologies of livestock abortion in northern Tanzania. Scientific Reports, 12.4. Ullah, Q.,  Jamil, T., Muhammad, S., Iqbal, M., Neubauer, I., 2022. Q fever – A Neglected Zoonosis. Microorganisms. 2022; 10(8):1530. https://doi.org/10.3390/microorganisms100815305. Muskens, J., Van Maanen, C. & Mars, M. H., 2011. Dairy cows with metritis: Coxiella burnetii test results in uterine, blood and bulk milk samples. Veterinary Microbiology 147(1-2), pp. 186-1896. Velasova et al. (2017) Herd-level prevalence of selected endemic infectious diseases of dairy cows in Great Britain. J Dairy Sci 100(11) pp9215-9233; DEFRA (2021)This study aim was to determine the prevalence of C. burnetii on acommercial dairy farm in Scotland with previous history of C. burnetii.Longitudinal sampling will serve to quantify the number of individualsshedding C. burnetii DNA.1School of Biodiversity, One Health and Veterinary Medicine, University of Glasgow, UKGriffin Weller1, Richard Vazquez1, Kathryn Allan1, Lorenzo Viora1, Jo Halliday1Investigating the prevalence of Coxiella burnetiiinfection in a dairy herd in ScotlandMaterials and MethodsA 900-cow commercial dairy farm in Scottland, UK was recruited in thisstudy following initial positive screening for C. burnetii via bulk tank milkPCR (under University of Glasgow ethics number EA34/22). Vaginal swabs were collected from cows within seven days afterparturition. Before sampling, the vulva of the cow was thoroughlycleaned using a solution of Hibiscrub® (Regent Medical Ltd., UK) andsubsequent drying with a paper towel (Star Tissue Ltd., UK), a sterilecollection swab was then inserted through the vaginal to collect thevaginal fluids and immediately stored in an sterile Eppendorf tube with1x DNA/RNA Shield® (Zymo Research).The vaginal swabs were analyzed with qPCR using an IS1111 assay(Quantabio, US) on extracted bacterial DNA. Samples were tested using40-45 cycles following standard Qiagen RotoGene operating procedures.Data was entered into Microsoft Excel (Microsoft Corporation) andexported in R Studio (RStudio Team, 2020) for further statisticalanalysis.Figure 1. Post partum cow attending to newborn calf.A total of 346 vaginal swabs were collected between December 2022 toAugust 2023 and tested in seven separate ‘Runs’. Vaginal swab qPCRresults indicated that 95.5% (CI 95%; 92.7-97.4%) of the cows werepositive for C. burnetii (Cycle threshold (Ct) ≤ 40) and 90.6% (CI 95%;87.1-93.5%) of Ct scores indicated that these cows were activelyshedding C. burnetii (Ct ≤ 35). A total of 64 (18.2%) (CI 95%; 14.3-22.6%) samples had Ct scores (Ct ≤ 27) attributable to clinical disease(Figure 2). A greater (P<0.05) proportion of primiparous cows werepositive (Ct ≤ 35) for C. burnetii than multiparous cows (Figure 3).LactationCycle threshold scoreFigure 2. Scatter plot of the individual vaginal swab qPCR results indicating the cowspositive for C. burnetii (Ct ≤ 40, solid line), cows that were actively shedding C. burnetii(Ct ≤ 35; dashed line), and cows that C. burnetii could be attributable to clinical disease (Ct ≤ 27; dotted line) Figure 3. Box plot distribution of the IS1111 qPCR Ct scores by lactation group (Median values, solid lines in boxes)

Investigating the Prevalence and Impact of Coxiella burnetii Infection in Dairy Herds in Scotland

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Investigating the Prevalence and Impact of Coxiella burnetii Infection in Dairy Herds in Scotland

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