ABSTRACT
The in vitro activity of tulathromycin was evaluated against common bovine and porcine respiratory pathogens collected from outbreaks of clinical disease across eight European countries from 1998 to 2001. Minimum inhibitory concentrations (MICs) for one isolate of each bacterial species from each outbreak were determined using a broth microdilution technique. The lowest concentrations inhibiting the growth of 90% of isolates (MIC90) for tulathromycin were 2 microg/ml for Mannheimia (Pasteurella) haemolytica, 1 microg/ml for Pasteurella multocida (bovine), and 2 microg/ml for Pasteurella multocida (porcine) and ranged from 0.5 to 4 microg/ml for Histophilus somni (Haemophilus somnus) and from 4 to 16 microg/ml for Actinobacillus pleuropneumoniae. Isolates were retested in the presence of serum. The activity of tulathromycin against fastidious organisms was affected by culture conditions, and MICs were reduced in the presence of serum.
Subject(s)
Anti-Bacterial Agents/pharmacology , Disaccharides/pharmacology , Gram-Negative Bacteria/drug effects , Heterocyclic Compounds/pharmacology , Pasteurellosis, Pneumonic/epidemiology , Swine Diseases/epidemiology , Actinobacillus pleuropneumoniae/drug effects , Actinobacillus pleuropneumoniae/isolation & purification , Animals , Anti-Bacterial Agents/therapeutic use , Cattle , Disaccharides/therapeutic use , Europe/epidemiology , Gram-Negative Bacteria/isolation & purification , Haemophilus somnus/drug effects , Haemophilus somnus/isolation & purification , Heterocyclic Compounds/therapeutic use , In Vitro Techniques , Mannheimia haemolytica/drug effects , Mannheimia haemolytica/isolation & purification , Microbial Sensitivity Tests/veterinary , Pasteurella multocida/drug effects , Pasteurella multocida/isolation & purification , Pasteurellosis, Pneumonic/blood , Pasteurellosis, Pneumonic/drug therapy , Pasteurellosis, Pneumonic/microbiology , Swine , Swine Diseases/blood , Swine Diseases/drug therapy , Swine Diseases/microbiologyABSTRACT
The efficacy of tulathromycin in the treatment (phase 1) and prevention (phase 2) of bovine respiratory disease (BRD) was evaluated on commercial farms in France, Germany, Italy, and Spain. In phase 1, commingled cattle with clinical BRD were treated with tulathromycin (n = 128) or florfenicol (n = 125) on day 0. Similar percentages of animals showed sustained clinical improvement at day 14 (tulathromycin 83.3% versus florfenicol 81.0%) and had not relapsed by day 60 (tulathromycin 63.3% versus florfenicol 58.4%). In phase 2, healthy in-contact cattle were treated with tulathromycin (n = 492), tilmicosin (n = 494), or saline (n = 265) on day 0. Significantly more (P = .0001) tulathromycin-treated cattle remained healthy to day 14 (92.4%) than tilmicosin-treated (83.7%) or saline-treated (63.7%) cattle, and this was maintained through day 60 (tulathromycin 85.4% versus tilmicosin 75.1% and saline 56.2%). Tulathromycin was highly effective in the treatment and prevention of BRD.
Subject(s)
Anti-Bacterial Agents/therapeutic use , Disaccharides/therapeutic use , Disease Outbreaks/veterinary , Heterocyclic Compounds/therapeutic use , Pasteurellosis, Pneumonic/epidemiology , Pasteurellosis, Pneumonic/prevention & control , Animals , Anti-Bacterial Agents/administration & dosage , Cattle , Disaccharides/administration & dosage , Disease Outbreaks/prevention & control , Europe/epidemiology , Haemophilus somnus/isolation & purification , Heterocyclic Compounds/administration & dosage , Injections, Subcutaneous/veterinary , Macrolides/administration & dosage , Macrolides/therapeutic use , Mannheimia haemolytica/isolation & purification , Mycoplasma bovis/isolation & purification , Pasteurella multocida/isolation & purification , Pasteurellosis, Pneumonic/drug therapy , Pasteurellosis, Pneumonic/microbiology , Thiamphenicol/administration & dosage , Thiamphenicol/analogs & derivatives , Thiamphenicol/therapeutic use , Tylosin/administration & dosage , Tylosin/analogs & derivatives , Tylosin/therapeutic useABSTRACT
The efficacy of tulathromycin in the treatment of bovine respiratory disease (BRD) due to Mycoplasma bovis was determined following experimental infection. Two highly pathogenic strains of M. bovis (with minimum inhibitory concentration values for tulathromycin of 1 and >64 microg/ml) were inoculated into 145 calves. Four days after inoculation, calves with clinical BRD were treated subcutaneously with saline or tulathromycin (2.5 mg/kg). Compared with saline, BRD-related withdrawals, peak rectal temperatures, and lung lesion scores were significantly lower for tulathromycin-treated calves (P < .01). Tulathromycin was highly effective in the treatment of BRD due to M. bovis in calves regardless of the minimum inhibitory concentration of the challenge strain (1 or >64 microg/ml).
Subject(s)
Anti-Bacterial Agents/therapeutic use , Cattle Diseases/drug therapy , Disaccharides/therapeutic use , Heterocyclic Compounds/therapeutic use , Mycoplasma Infections/veterinary , Mycoplasma bovis , Animals , Animals, Newborn , Anti-Bacterial Agents/administration & dosage , Anti-Bacterial Agents/pharmacology , Body Temperature , Cattle , Cattle Diseases/microbiology , Cattle Diseases/pathology , Dairying , Disaccharides/administration & dosage , Disaccharides/pharmacology , Female , Heterocyclic Compounds/administration & dosage , Heterocyclic Compounds/pharmacology , Injections, Subcutaneous/veterinary , Male , Microbial Sensitivity Tests , Mycoplasma Infections/drug therapy , Mycoplasma bovis/classification , Mycoplasma bovis/drug effects , Severity of Illness Index , Treatment OutcomeABSTRACT
The clinical efficacy of tulathromycin in the treatment of natural outbreaks of swine respiratory disease (SRD) was evaluated at five European sites. Pigs (1 to 6 months of age) exhibiting clinical signs of SRD were treated intramuscularly with tulathromycin (n = 247) at 2.5 mg/kg on day 0 versus either tiamulin (n = 102) at 15 mg/kg on days 0, 1, and 2 (Germany, the Netherlands, and the United Kingdom) or florfenicol (n = 20) at 15 mg/kg on days 0 and 2 (France). Actinobacillus pleuropneumoniae, Pasteurella multocida, and Mycoplasma hyopneumoniae infections were the most frequently diagnosed pathogens. For both tulathromycin-treated animals and those treated with tiamulin or florfenicol, there were significant (P = .0001) reductions in mean rectal temperature and the severity of abnormal clinical signs on days 2 and 10 compared with day 0. There were no significant differences (P > .05) between treatments in average daily weight gain. Tulathromycin was found to be safe and highly effective in the treatment of natural outbreaks of SRD.