Several novel 15-membered-ring macrolide agents (azalide 1, triamilides 2 and 3, and the azalide 3,6-ketal 4) were identified as potential antibacterial agents against Mannheimia (formerly named as Pasteurella) haemolytica, Pasteurella multocida, Haemophilus somnus and Actinobacillus pleuropneumoniae, important etiological agents of bovine and porcine respiratory disease. Compound 3 is the majo...

Materials and methods: Purebred Yorkshire pigs (N = 192) were each assigned to one of five treatment groups. Groups 1a and 1b remained PRRSV-negative (controls), while Groups 2, 3, and 4 were injected with a modified-live (MLV) PRRSV vaccine. Groups 1b and 2 were fed non-medicated feed. Rations contained tilmicosin at 400 mg per kg for Group 1a and Group 4 and 200 mg per kg for Group 3. Blood s...

OBJECTIVE To examine the effectiveness of mass medication with long acting antibiotics at feedlot entry on lot-fed Australian domestic cattle during a period of high risk for bovine respiratory disease (BRD). DESIGN Systematic allocation at feedlot entry of tilmicosin, long acting oxytetracycline or no antibiotic treatment, to cattle lot fed for the Australian domestic market. Comparisons of ...

A systematic analysis of the bacteriostatic/bactericidal effect of several antibiotics used in veterinary medicine was carried out by time-kill kinetic analysis using P. haemolytica, P. multocida, A. pleuropneumoniae, and E. coli. The antibiotics tested were enrofloxacin, danofloxacin, erythromycin, tilmicosin, penicillin G, ceftiofur and tetracycline. Unexpectedly, the antibiotics well charact...

Tilmicosin was administered intravenously and subcutaneously at a dose rate of 10 mg/kg bwt to determine its concentration in blood and bronchial secretion as well as its kinetic behavior in healthy and Pasteurella haemolytica type A1-infected calves. Sever acute bronchopneumonia was induced in 10 calves by inoculating them intra-tracheally with P. haemolytica type A1. The calves were treated w...

The aim of this study is to determine the pharmacokinetics of tylosin and tilmicosin in serum and milk in healthy Holstein breed cows (n = 12) and reevaluate the amount of residue in milk. Following the intramuscular administration of tylosin, the maximum concentrations (C max) in serum and milk were found to be 1.30 ± 0.24 and 4.55 ± 0.23 µg/mL, the time required to reach the peak concentratio...

A high-performance liquid chromatographic (HPLC) method for the simultaneous determination of tilmicosin, tylosin, spiramycin, and its major metabolite neospiramycin was developed that is suitable for porcine, bovine, and poultry muscles. Macrolide residues were extracted from muscle with acetonitrile, fat was removed by liquid-liquid extraction with isooctane, and the extract was then cleaned ...

Dust is an environmental stressor and can become extensive in agricultural production systems. Thirty-six female, Spanish goats (average BW 21.1 kg, SEM = 1.31; age = 4 mo) were randomly assigned to simulated dust events or no dust, with or without tilmicosin phosphate treatment in a 2 x 2 factorial arrangement of treatments to determine effects on performance, rectal temperature, and leukocyte...

The macrolide class of antibiotics, including tylosin and tilmicosin, is widely used in the veterinary field for prophylaxis and treatment of mycoplasmosis. In vitro susceptibility testing of 50 strains of M. gallisepticum isolated in Israel during the period 1997-2010 revealed that acquired resistance to tylosin as well as to tilmicosin was present in 50% of them. Moreover, 72% (13/18) of the ...