Early detection of problem implants using infrared thermography

Thermal imaging of feedlot cattle ears is a noninvasive diagnostic tool that aids in identifying properly placed or abscessed growth-promoting implants. Thirty-two calves were used to determine if abscessed and normal, functional implants could be identified and differentiated using infrared thermography. Infrared images were taken at implantation on days 2, 4, 7, 14, and 21 after implantation. Abscessed implants were easily identified. Use of thermal imaging can verify implant administration and, thus, has the potential to immediately impact feedlot quality assurance programs

Influence of melengesterol acetate (MGA®) and Implus-H® implants on rate of gain, feed efficiency, and carcass characteristics of culled beef cows fed a high concentrate ration

No statistical differences were detected in feedlot performance or carcass traits between control culled beef cows and those that were treated with melengesterol acetate (MGA®) and/or Implus-H® when fed in a feedyard for 56 days before slaughter. All groups performed well, indicating that this practice may be used to improve the market value of culled cows. Cow health during the feeding period is a major concern

Prevalence of Escherichia coli O157:H7 in cow-calf herds in Kansas

Fecal samples from cows and calves and samples of water sources were collected monthly for 8 months from 10 Kansas cow-calf farms to determine the prevalence of E. coli O157:H7. The bacterium was found in 8% of fecal samples from cows that were within 24 hours of calving, 1.4% of fecal samples from cows which were not within 24 hours of calving, 1.4% of calf fecal samples, and 1.5% of water samples. E. coli O157:H7 was identified from at least one sample on all farms

Theoretical and experimental study of tropylium formation from substituted benzylpyridinium species

Fragmentation pathways of unsubstituted and substituted benzylpyridinium compounds were investigated using mass-analysed kinetic energy (MIKE) technique in combination with high level of quantum chemical calculations in the gas phase. Fast atom bombardment (FAB) source was used for ionisation of the studied compounds. The formation of both benzylium and tropylium species were investigated. Hybrid Hartree-Fock/Density Functional Theory calculations have been performed to assess the geometries and the energies of the transition states and intermediates. For each cases, different reaction pathways were investigated, and particularly in the case of the formation of tropylium species, the formation of the seven-membered ring before or after the loss of pyridine were studied. The effect of para-methyl and para-methoxy substituents on the activation energy of the rearrangement process to form thermodynamically stable tropylium compounds has been studied. Theoretical calculations showed competition between direct bond cleavage and rearrangement reactions to form benzylium and tropylium compounds, respectively. Experimental results also suggested that the rearrangement process takes place to yield stable tropylium under “soft ionisation techniques”, such as FAB

MeMoVolc report on classification and dynamics of volcanic explosive eruptions

Classifications of volcanic eruptions were first introduced in the early twentieth century mostly based on qualitative observations of eruptive activity, and over time, they have gradually been developed to incorporate more quantitative descriptions of the eruptive products from both deposits and observations of active volcanoes. Progress in physical volcanology, and increased capability in monitoring, measuring and modelling of explosive eruptions, has highlighted shortcomings in the way we classify eruptions and triggered a debate around the need for eruption classification and the advantages and disadvantages of existing classification schemes. Here, we (i) review and assess existing classification schemes, focussing on subaerial eruptions; (ii) summarize the fundamental processes that drive and parameters that characterize explosive volcanism; (iii) identify and prioritize the main research that will improve the understanding, characterization and classification of volcanic eruptions and (iv) provide a roadmap for producing a rational and comprehensive classification scheme. In particular, classification schemes need to be objective-driven and simple enough to permit scientific exchange and promote transfer of knowledge beyond the scientific community. Schemes should be comprehensive and encompass a variety of products, eruptive styles and processes, including for example, lava flows, pyroclastic density currents, gas emissions and cinder cone or caldera formation. Open questions, processes and parameters that need to be addressed and better characterized in order to develop more comprehensive classification schemes and to advance our understanding of volcanic eruptions include conduit processes and dynamics, abrupt transitions in eruption regime, unsteadiness, eruption energy and energy balance

Prevalence, antibiotic susceptibility, and genetic diversity of Salmonella, Campylobacter, and Escherichia coli O157:H7 collected at four Kansas beef cattle feedyards over 13 months

Salmonella, Campylobacter, and Eschericia coli O157:H7 are important foodborne pathogens, but longitudinal studies of their prevalence in beef cattle feedyards have not been done. Our long- term study involved 24,556 samples taken from beef cattle feedyards found overall prevalence’s of 4.87% for Salmonella, 20.1% for Campylobacter in hospital pen fecal samples, and 0.20% for E. coli O157:H7. Yard and pen differences (P<0.05) were detected. All 53 E. coli O157:H7 isolates were resistant to Talmicosin and Erythromycin, two antimicrobials used in food animal medicine. Their genetic diversity was high and did not indicate the presence of resident strains at the yards studied. Salmonella, Campylobacter, and E. coli O157:H7 were probably brought into the yards by shipments of new cattle. Many of these organismswere susceptible to antibiotics commonly used to treat beef cattle

Early detection of problem implants using infrared thermography

Thermal imaging of feedlot cattle ears is a noninvasive diagnostic tool that aids in identifying properly placed or abscessed growth-promoting implants. Thirty-two calves were used to determine if abscessed and normal, functional implants could be identified and differentiated using infrared thermography. Infrared images were taken at implantation on days 2, 4, 7, 14, and 21 after implantation. Abscessed implants were easily identified. Use of thermal imaging can verify implant administration and, thus, has the potential to immediately impact feedlot quality assurance programs

Some consequences of fluid overpressure on sills emplacement: theoretical and experimental approaches

International audienc

Effects of tetracycline on shedding of susceptible and resistant salmonella spp. experimentally inoculated into pigs

The objective of this experiment was to study the influence of tetracycline on the transfer of antibiotic resistance in an in vivo swine model experimentally infected with antibiotic-resistant and antibiotic susceptible Salmonella spp. Tetracycline reduced the amount and duration of shedding of tetracycline- susceptible Salmonella. However, tetracycline had no effect on shedding of resistant Salmonella. We also have evidence that resistance was transferred from the resistant to the susceptible strain of Salmonella

Effects of antibiotics on shedding of salmonella typhimurium in experimentally inoculated pigs

The objective of this experiment was to determine if antibiotics used as feed additives and disease treatment for livestock affect duration of shedding and colonization of tissues with Salmonella typhimurium in pigs. No statistically significant difference was detected in duration or amount of shedding of S. typhimurium between pigs receiving antibiotics and control pigs. Antibiotics prevented colonization of tissues by S. typhimurium. The odds (OR= .02) of isolating S. typhimurium in at least one of four tissues examined were significantly less from pigs treated with antibiotics than from control pigs (two-tailed Fisher exact test, P= .009)