Mass screening for antimicrobial resistant Escherichia coli in dairy cows in northern New South Wales

Abstract

Antimicrobial resistance was uncommon in E coli in the population of dairy cows studied. HGMF and image analysis is an effective tool for detecting rare forms of resistant E coli that are not uniformly distributed in livestock populations.

Manure as a Source of Antibiotic-Resistant Escherichia coli and Enterococci: a Case Study of a Wisconsin, USA Family Dairy Farm

“…The observed antibiotic resistance patterns of E. coli and enterococci were generally consistent to the findings of many previous studies (Alexander et al 2008;Cupakova and Lukasova 2003;Holzel et al 2010;Jordan et al 2005;Sato et al 2005;Sayah et al 2005). Sato et al (2005), for instance, tested antibiotic resistance of E. coli isolated from manure samples collected from both organic and conventional Wisconsin dairy farms and found prevalence of antibiotic resistance to antibiotics such as ampicillin, cephalothin, and tetracycline.…”

“…Due to the widespread use of antibiotics in the animal farm environment for both therapeutic and growth promotion purposes, high levels of antibiotic-resistant bacteria were found in animal waste (Halbert et al 2006;Hofacre et al 2000;Holzel and Bauer 2008;Jordan et al 2005;Kumar and Schweizer 2005;Mirzaagha et al 2009;Parveen et al 2006;Ray et al 2006;Sapkota et al 2007;Sato et al 2004Sato et al , 2005Smith et al 2002;Varga et al 2008Varga et al , 2009. Manure, with an annual production rate of 133 million tons in dry weight in the USA alone, represents a major source of antibiotic-resistant bacteria that were detected in the natural environment.…”

Effect of Antimicrobial Consumption and Production Type on Antibacterial Resistance in the Bovine Respiratory and Digestive Tract

“…In adult dairy cattle, resistance among E . coli was sparse and in agreement with an Australian study by Jordan and colleagues [ 19 ]. The age related decline in overall resistance of enteric E .…”

Phenotypic and genotypic profiling of antimicrobial resistance in enteric Escherichia coli communities isolated from finisher pigs in Australia

“…In contrast, the evaluation of enteric indicator microbes such as E. coli for AMR traits allows more statistically robust sampling of herds, animals and isolates and provides a strong basis for population‐level inferences . Previous studies have exploited the ubiquitous nature of E. coli in gut microbiota to demonstrate the power of mass screening for defining the epidemiology of antibiotic resistance in bacterial communities from pigs and cattle …”

“…All plates generated from the master grid were incubated at 37°C overnight and the presence or absence of colonies recorded by the capture of jpeg images of the entire grid using a scientific‐grade digital camera (Pixelink PL‐B741, Pixelink, Ottawa, Canada). Images corresponding to a single pooled faecal sample were analysed collectively using HGMF‐RES software, which identifies E. coli colonies based on possession of a strong pink colour when growing on MacConkey agar (indicating lactose fermentation) while also exhibiting a purple colour on CHROMagar media (indicating glucuronidase and galactosidase activity). The software also was used to distinguish and exclude from analysis colonies not derived from a colony present on the master grid and replicated colonies that did not appear on the CHROMagar final grid.…”