Quantitative assessment of agricultural water and fecal matter for prevalence of A. faecis and A. lanthieri.


Khan, I.U.H., Miltenburg, M.G., Cloutier, M., Islam, O., Lapen, D.R., Wilkes, G., Talbot, G., Topp, E. 2018. Quantitative assessment of agricultural water quality, human and animal feces for prevalence of Arcobacter faecis and A. lanthieri. ASM (American Society for Microbiology) Microbe 2018. June 07-11, 2018, Atlanta, GA.


Background: Arcobacter faecis and A. lanthieri, isolated from human and animal fecal sources, are two newly classified members of genus Arcobacter. Since these species are closely related to A. butzleri, A. cryaerophilus and A. skirrowii that cause diseases in human and animals, this study investigated the prevalence of these species in surface water collected from a Canadian agricultural watershed located in South Nation River watershed eastern Ontario and fecal samples from human and animal sources by culture-independent direct DNA-based species-specific quantitative PCR assay.
Methods: Initially, we developed and optimized species-specific quantitative real-time PCR assays based on the variable regions of rpoB and gyrA housekeeping genes for A. faecis and A. lanthieri, respectively. Specificity of primers and amplicons of each target reference strains were verified and confirmed by dissociation curve analysis using variable DNA concentrations. In order to demonstrate the utility of the approach in real environmental situations, the developed protocol was further validated by quantifying prevalence of each species in environmental samples collected from water and various fecal sources. A total of 306 agricultural surface water samples, 19 human and 250 livestock, poultry and other domestic animal fecal samples were analyzed.
Results: Overall, A. faecis was detected at the frequency of 14% (n= 42) in water with concentrations ranging from 2.5x103 to 4.9x105 cells/100 ml compared to fecal samples (7%; n= 19) where concentration ranges from 1.7x101 to 1.2x104 cells/g, respectively. However, A. lanthieri was detected at a low frequency in water (3%; n= 8) and fecal samples (10%; n= 27) with concentrations ranging from 1.8x104 to 4.1x105 cells/100 ml in water and 4.8x101 to 3.3x104 cells/g in fecal samples.