TY - JOUR
T1 - Presence of antibiotic-resistant commensal bacteria in samples from agricultural, city, and national park environments evaluated by standard culture and real-time PCR methods
AU - Yang, Hua
AU - Byelashov, Oleksandr A.
AU - Geornaras, Ifigenia
AU - Goodridge, Lawrence D.
AU - Nightingale, Kendra K.
AU - Belk, Keith E.
AU - Smith, Gary C.
AU - Sofos, John N.
PY - 2010
Y1 - 2010
N2 - This study examined the presence of antibiotic-resistant commensal bacteria among cattle operations representing areas heavily affected by agriculture, city locations representing areas affected by urban activities and indirectly affected by agriculture, and a national park representing an area not affected by agriculture. A total of 288 soil, fecal floor, and water samples were collected from cattle operations, from the city of Fort Collins, and from Rocky Mountain National Park (RMNP) in Colorado. In addition, a total of 42 new and unused feed, unused bedding, compost, and manure samples were obtained from the cattle operations. Total, tetracycline-resistant, and ceftiofur-resistant bacterial populations were enumerated by both standard culture plating and real-time PCR methods. Only wastewater samples from the cattle operations demonstrated both higher tetracycline-resistant bacterial counts (enumerated by the culture plating method) and tetracycline resistance gene copies (quantified by real-time PCR) compared to water samples collected from non-farm environments. The ceftiofur resistance gene, blaCMY-2, was not detectable in any of the samples, while the tetracycline resistance genes examined in this study, tet(B), tet(C), tet(W), and tet(O), were detected in all types of tested samples, except soil samples from RMNP. Tetracycline resistance gene pools quantified from the tet(O) and tet(W) genes were bigger than those from the tet(B) and tet(C) genes in fecal and water samples. Although only limited resistance genes, instead of a full set, were selected for real-time PCR quantification in this study, our results point to the need for further studies to determine natural and urban impacts on antibiotic resistance.
AB - This study examined the presence of antibiotic-resistant commensal bacteria among cattle operations representing areas heavily affected by agriculture, city locations representing areas affected by urban activities and indirectly affected by agriculture, and a national park representing an area not affected by agriculture. A total of 288 soil, fecal floor, and water samples were collected from cattle operations, from the city of Fort Collins, and from Rocky Mountain National Park (RMNP) in Colorado. In addition, a total of 42 new and unused feed, unused bedding, compost, and manure samples were obtained from the cattle operations. Total, tetracycline-resistant, and ceftiofur-resistant bacterial populations were enumerated by both standard culture plating and real-time PCR methods. Only wastewater samples from the cattle operations demonstrated both higher tetracycline-resistant bacterial counts (enumerated by the culture plating method) and tetracycline resistance gene copies (quantified by real-time PCR) compared to water samples collected from non-farm environments. The ceftiofur resistance gene, blaCMY-2, was not detectable in any of the samples, while the tetracycline resistance genes examined in this study, tet(B), tet(C), tet(W), and tet(O), were detected in all types of tested samples, except soil samples from RMNP. Tetracycline resistance gene pools quantified from the tet(O) and tet(W) genes were bigger than those from the tet(B) and tet(C) genes in fecal and water samples. Although only limited resistance genes, instead of a full set, were selected for real-time PCR quantification in this study, our results point to the need for further studies to determine natural and urban impacts on antibiotic resistance.
KW - Agricultural
KW - Ceftiofur resistance
KW - City and national park environments
KW - Real-time PCR
KW - Standard culture plating
KW - Tetracycline resistance
UR - http://www.scopus.com/inward/record.url?scp=77958012605&partnerID=8YFLogxK
U2 - 10.1139/W10-060
DO - 10.1139/W10-060
M3 - Article
C2 - 20921986
AN - SCOPUS:77958012605
SN - 0008-4166
VL - 56
SP - 761
EP - 770
JO - Canadian Journal of Microbiology
JF - Canadian Journal of Microbiology
IS - 9
ER -