A Longitudinal Study of the Establishment and Proliferation of Enterococcus on a Dairy Farm

Enterococci are Gram-positive, facultative anaerobic cocci. They are found in many environments (including milk and dairy products, vegetables, plants, cereals, and meats). Enterococci are considered commensal organisms, but can also be opportunistic pathogens associated with morbidity and mortality of humans and animals. A longitudinal study of antibiotic resistance of Enterococcus to ampicillin, erythromycin, and tetracycline was conducted on an academic teaching farm. Environmental samples were collected by drag swabs at select locations prior to and after the introduction of livestock. All samples were initially processed and screened with specialized media, and then replica plated on tryptic soy agar containing a predetermined amount of antibiotic. There was some variation in the quantity of bacterial and antibiotic-resistant colonies; however, resistance to tetracycline was extremely high. The increases of too numerous to count populations were not time-dependent and appeared consistently after the placement of cows. There is little information on the prevalence and epidemiology of antibiotic resistance of Enterococci outside of the hospital setting, including on dairy farms. Longitudinal studies are important in providing insight into the dynamics of establishment and proliferation of bacteria and of antibiotic resistance

Maintaining the safety and quality of beef carcass meat

Contamination of animal carcasses during slaughtering procedures is undesirable, but unavoidable in the conversion of live animals to meat for consumption. Internal muscle tissues are essentially sterile, and most initial contamination of red meat carcasses is contributed by the hide during removal (Elmonssalami and Wassef, 1971; Gill and Penny, 1979; Gill et al., 1976). The exposed surface of the hide and the hair accumulate dust, dirt and faecal material, and this is the primary source of bacterial contamination during slaughter (Ayres, 1955; Shotts et al., 1961). The factors that affect the extent of this contamination are reviewed by Patterson (1969) and Grau et al. (1968). Much of the microflora transferred to the tissue surfaces, while aesthetically undesirable, is nonpathogenic; however, pathogens such as Salmonella, Campylobacter and pathogenic Escherichia coli can be present

Time-Lapse Imaging in Polar Environments

Although the drivers of climate change and its consequences in polar regions are becoming better understood [Holland and Bitz, 2003] and well monitored [Serreze et al., 2002; Doran et al., 2002b], measuring the responses of polar landscapes to changing climate boundary conditions is challenging: Polar landscapes typically respond slowly to warming but abruptly to melting [Gooseff et al., 2011]