in order to investigate effects of addition of salvia mirzayanii essence and comparison with antibiotic an experiment was conducted as dietary a completely of the randomized design with 5 treatments, and 5 replicates with 12 chickens per replicate for 42 days with treatments control, virginiamycin antibiotic 10% (100 ppm) and three levels of s. mirzayanii essence (200, 400 and 600 ppm). weight ...

a total of 528 day-old ross 308 male broilers were used to study the effect of antibiotic, probiotic, prebiotic and organic acid on performance, cecal coliform load and internal organs’ weight. the chickens were placed into 6 groups with 4 replicates and 22 chickens per pen. six dietary treatments included: 1) negative control as basal diet without any antibiotic growth promoter and coccidiosta...

a research study was conducted to evaluate the effects of three herbal extracts and an antibiotic –virginiamycin- on growth performance, immune system, blood factors and selected intestinal bacterial populations in broiler chickens. a total of four hundred and eighty 1-day old male broiler chicks were assigned to the basal diet (control) , basal diet supplemented with 15 ppm of virginiamyci...

The M component of virginiamycin inhibited growth of Plectonema boryanum under both photoautotrophic and heterotrophic conditions. Though the S component of this antibiotic had no apparent activity per se, it enhanced the inhibitory action of its partner. Cells incubated with suitable concentrations of either M or M + S stopped growing and lysed. Loss of the colony-forming capacity occurred qui...

Virginiamycin M inhibits both peptide bond formation and binding of aminoacyl-tRNA to bacterial ribosomes, and induces a lasting inactivation of the 50 S subunit (50 S). In the present work, the effects of this antibiotic on the acceptor and donor sites of peptidyltransferase have been explored, in the presence of virginiamycin M as well as after its removal. Virginiamycin M inhibited the bindi...

this study was conducted to investigate the effects of the medicinal plant yarrow (achillea millefolium l.), a probiotic (primalac) and an antibiotic (virginiamycin) on gastrointestinal tract (git) characteristics, microbial populations, immune response, serum lipids and growth performance of broiler chickens. a total of 250 one-day old male broilers (ross 308) were randomly allocated to 5 trea...

background: with the removal of antibiotic as growth promoters from poultry diets, it is of interest to investigate potential alternatives to maintain good growth performance and good intestinal microbial populations in these birds. numerous additives such as probiotics, prebiotics, organic acids, enzymes and herbal extracts used extensively in poultry feed. objective: the study was conducted t...

Antibiotics have been common feed additives in poultry rations as growth promoters to improve performance via reducing burden of pathogens. However, it has been increasing pressure to reduce or even eliminate antibiotic usage in poultry feed due to the negative human health issues of antibiotic resistance. Safe broiler production without medication and vaccination was conducted at present study...

BarA of Streptomyces virginiae is a specific receptor protein for virginiae butanolide (VB), one of the gamma-butyrolactone autoregulators of the Streptomyces species, and acts as a transcriptional regulator controlling both virginiamycin production and VB biosynthesis. The downstream gene barB, the transcription of which is under the tight control of the VB-BarA system, was found to be transcr...

Three balance trials, each involving 12 crossbred gilts averaging 35.2 kg body weight, were conducted to determine the effects of dietary fiber and virginiamycin on nutrient digestibility, mineral absorption and retention, and digesta rate of passage (RP). Two levels of fiber (13.5 and 20.2% neutral detergent fiber) and two levels of virginiamycin (0 and 11 ppm) were used in a 2 X 2 factorial a...