Cost Benefits of Coccidiosis Prevention in a Feedlot

The objective of today\u27s food animal enterprise is to produce a quality product while at the same time providing maximum economic return to the producer. Many factors are involved, including herd health programs, which work to maintain animal health and to decrease economic losses due to disease. A herd health preventive medicine program will increase the costs of production, but it will increase the economic returns if the level of performance is improved

Viscoelastic analysis of high molecular weight, alkali-denatured DNA from mouse 3T3 cells.

Alkaline lysates of mouse 3T3 cells showed viscoelastic properties characteristic of very large molecules of single-stranded DNA. The viscoelastic retardation time and the sensitivity to low doses of nitrogen mustard and of X-irradiation suggest a molecular weight in excess of 10-10 daltons. Contact-inhibited cells yielded larger single strands than actively growing cells

Cost Benefits of Coccidiosis Prevention in a Feedlot

The objective of today's food animal enterprise is to produce a quality product while at the same time providing maximum economic return to the producer. Many factors are involved, including herd health programs, which work to maintain animal health and to decrease economic losses due to disease. A herd health preventive medicine program will increase the costs of production, but it will increase the economic returns if the level of performance is improved.</p

Viscoelastic characterization of single-stranded DNA from Escherichia coli.

Single-stranded DNA released from E. coli wild type and mutant cells by alkaline-EDTA-detergent was analyzed using the recently developed biophysical technique of viscoelastometry. Under the lysis conditions used, it was possible to detect single strands of molecular weight approximately 2 times 10-9 daltons. Little difference was detected in the size of single-stranded DNA from log phase vs. stationary phase cultures, or from cells treated with chloramphenicol to allow completion of replicating chromosomes. The largest single strands from ligase overproducing, endonuclease minus, and pol A1 mutants were likewise of approximately the same size as wild type, but were present in smaller yields. The reduction in single-strand molecular weight as a result of heating intact cells was investigated as a function of time and temperature. Heating at 37 degrees C for up to 20 min produced no additional single-strand breaks, but temperatures from 45 to 65 degrees introduced breaks. Solutions maintained at pH 12.5 were not stable indefinitely, and the relative viscosity of such solutions was found to decrease over a period of several hours

Animal and Human Multidrug-Resistant, Cephalosporin-Resistant Salmonella Isolates Expressing a Plasmid-Mediated CMY-2 AmpC β-Lactamase

Salmonella spp. are important food-borne pathogens that are demonstrating increasing antimicrobial resistance rates in isolates obtained from food animals and humans. In this study, 10 multidrug-resistant, cephalosporin-resistant Salmonella isolates from bovine, porcine, and human sources from a single geographic region were identified. All isolates demonstrated resistance to cephamycins and extended-spectrum cephalosporins as well as tetracycline, chloramphenicol, streptomycin, and sulfisoxazole. Molecular epidemiological analyses revealed eight distinct chromosomal DNA patterns, suggesting that clonal spread could not entirely explain the distribution of this antimicrobial resistance phenotype. However, all isolates encoded an AmpC-like β-lactamase, CMY-2. Eight isolates contained a large nonconjugative plasmid that could transform Escherichia coli. Transformants coexpressed cephalosporin, tetracycline, chloramphenicol, streptomycin, and sulfisoxazole resistances. Plasmid DNA revealed highly related restriction fragments though plasmids appeared to have undergone some evolution over time. Multidrug-resistant, cephalosporin-resistant Salmonella spp. present significant therapeutic problems in animal and human health care and raise further questions about the association between antimicrobial resistance, antibiotic use in animals, and transfer of multidrug-resistant Salmonella spp. between animals and man