By microbial transformation of tylosin (I), the following eight new acyl derivatives were obtained: 3-acetyltylosin (II), 3-propionyltylosin (III), 4"-butyryltylosin (IV), 4"-isovaleryltylosin (V), 3-acetyl-4"-butyryltylosin (VI), 3-acetyl-4"-isovaleryltylosin (VII), 3-propionyl-4"-butyryltylosin (VIII) and 3-propionyl-4"-isovaleryltylosin (IX).

Synthesis is described for the haptens 23-demycinosyl-23-deoxy-23-(3-aminoprop-1-yl)-aminotilmicosin (6) from 5-O-mycaminosyltylonolide (OMT) and for 23-demycinosyl-23-deoxy-23-(3-aminoprop-1-yl)-amino-20-dihydrotylosin (10) from demycinosyltylosin (DMT), respectively. The mild reaction conditions used to synthesize the second hapten, DMT derivative 10, were necessary to overcome instabilities ...

Previous in vitro data showed that Fusobacterium necrophorum was inhibited by limonene. We further evaluated effects of limonene on growth of F. necrophorum in vitro as well as on ruminal concentrations of F. necrophorum in vivo. With in vitro cultivation in anaerobic brain-heart infusion broth, limonene decreased growth of F. necrophorum. Thymol also reduced growth of F. necrophorum, but it wa...

Liver abscesses are the primary liver abnormality of feedlot cattle at slaughter. The incidence of liver abscesses is highly variable, but generally ranges from 10% to 20%. The incidence of total and the proportion of severely abscessed livers (A+) are greater in Holsteins fed for beef production and culled dairy cows than in beef breeds. The reason for the greater incidence of liver abscesses ...

background: repeated applications of animal manure as fertilizer are normal agricultural practices in malaysia that may release veterinary antibiotics to environment from treated animals. methods: environmental risk assessment (era) on 5 commonly used antibiotics and one hormone in malaysian broiler farm was calculated using the ratio of measured environmental concentration (mec) and predicted ...

in order to increase tylosin production by streptomyces fradiae, two mutagens, i. e. uv and ems (ethylmethanesulfonate) were used. death curves were plotted for these mutagens. optimum condition for obtaining mutants by uv radiation was determined by using a uv source lamp at a distance of 20 cm for 40-60 seconds. when ems was used at 4% (w/v) concentration, the best mutants were isolated after...

The new pleuromutilin derivative 81.723 hfu is extremely active against gram-positive organisms such as streptococci, staphylococci, and against mycoplasmas. A number of Shigella, Klebsiella, and Escherichia coli strains were also found to be quite susceptible to this new agent, whereas other gram-negative organisms like Pseudomonas aeruginosa, Proteus species, and Alcaligenes faecalis proved t...

In order to improve treatment and prophylactic measures for bacterial etiology diseases of pigs the combined antibiotic Tildox was developed in form a powder. One gram drag contains 100 mg doxycycline hydrochloride tylosin tartrate as active ingredients.The aim our research study efficacy enterococcal infection piglets.For experiment 3 groups 50 piglets rearing group were formed with pre-establ...

Four macrolide-resistant Arcanobacterium pyogenes isolates contained A2058T, A2058G, or C2611G (Escherichia coli numbering) mutations in their 23S rRNA genes. While these mutations conferred resistance to erythromycin, oleandomycin, and spiramycin, they did not confer resistance to tylosin.