Reduction of virginiamycin S with sodium borohydride produces allo- and normal-dihydro-virginiamycin S. Reduction of the tosylhydrazone of virginiamycin S with sodium cyanoborohydride affords deoxyvirginiamycin S. These compounds are less active than virginiamycin S. Like virginiamycin S they enhance the activity of virginiamycin M1.

BACKGROUND Virginiamycin use in poultry selects for Enterococcus faecium with cross-resistance to quinupristin-dalfopristin, a drug for vancomycin-resistant E. faecium in humans. We conducted an epidemiologic study of poultry exposures as risk factors for human carriage of quinupristin-dalfopristin-resistant E. faecium. METHODS Rectal or fecal samples for E. faecium testing were obtained from...

In pig production, the terms "growth promoter", "performance enhancer", and "digestive enhancer" include a diverse range of products ranging from simple chemicals (copper salts) to chemically produced antibacterial compounds (carbadox) to antibiotics (tylosin, avilamycin, salinomycin, virginiamycin). Most of the antibiotic group are produced during a fermentation process by yeasts, moulds, and ...

The effects of increasing aflatoxin B1 concentration (0, 0.75, 1.5 mg/kg) on broilers with or without necrotic enteritis or virginiamycin were determined. In the 23-d study, 22 male Cobb 500 chicks per pen were allotted to 12 treatments (3 × 2 × 2 factorial arrangement) with 8 replications. Intestines of 5 birds per pen were examined for lesions on d 21. Birds were allowed to consume feed and w...

The aim of this study was to compare the effects of three antibiotic alternatives with a control (Antibiotic-free) and an antibiotic diet on performance and gut morphology of broilers reared on litter. 600 day-old ROSS-308 chicks were assigned to 48 pens in a CRD design with 6 × 2 factorial arrangements, in which 2 levels of chick density (5 and 7.5 chicks/m2) and 6 experimental diets (control,...

In spite of a global concern on the transfer of antibiotic resistances (AR) via the food chain, limited information exists on this issue in species of Leuconostoc and Weissella, adjunct cultures used as aroma producers in fermented foods. In this work, the minimum inhibitory concentration was determined for 16 antibiotics in 34 strains of dairy origin, belonging to Leuconostoc mesenteroides (18...

The aim of this study was to compare the effects of three antibiotic alternatives with a control (Antibiotic-free) and an antibiotic diet on performance and gut morphology of broilers reared on litter. 600 day-old ROSS-308 chicks were assigned to 48 pens in a CRD design with 6 × 2 factorial arrangements, in which 2 levels of chick density (5 and 7.5 chicks/m2) and 6 experimental diets (control,...

The broiler (Gallus gallus domesticus) industry in the United States and several other countries routinely includes subtherapeutic levels of antibiotics such as roxarsone, virginiamycin, and bacitracin in the feed to improve bird growth yields. Large fractions of the antibiotics fed to the birds are excreted in manure (litter), which is often applied to soils to improve fertility. Some concerns...

Antibiotics are used in ethanol production to control bacteria from competing with yeast for nutrients during starch fermentation. However, there is no published scientifi c information on whether antibiotic residues are present in distillers grains (DG), co-products from ethanol production, or whether they retain their biological activity. Therefore, the objectives of this study were to quanti...