tiamulin and Pneumonia

Four field trials were carried out to evaluate the effect of feeding tiamulin hydrogen fumarate at 20 and 30 ppm to fattening pigs over an eight week period, on farms with histories of severe, complicated, enzootic pneumonia problems. These farms had a prevalence of pigs with pneumonic lesions from 81 to 94 per cent and a range between individual batches of 69 to 96 per cent. The results of the first three trials showed that tiamulin at 30 ppm significantly improved the weight gains and feed conversion efficiency of pigs, in comparison with controls and was superior to the groups fed 20 ppm tiamulin. A further trial with tiamulin at 30 ppm and controls only, confirmed the original findings. The overall average results showed that tiamulin improved average daily gain by 33 g (4.7 per cent) and feed conversion efficiency by 0.138 (4.7 per cent). This effect did not appear to result from a reduction in the total extent of pneumonic lesions and the possible reasons for this are discussed, but in the fourth trial the number of pigs requiring parenteral treatment was noticeably reduced.

Topics: Animal Feed; Animals; Body Weight; Clinical Trials as Topic; Diterpenes; Female; Male; Mycoplasma Infections; Pneumonia; Swine; Swine Diseases

The antibacterial effects of a combination of tiamulin and chlortetracycline in vitro against a number of field isolates of Pasteurella multocida, Haemophilus pleuropneumoniae and Bordetella bronchiseptica were examined. There was a marked synergism between the two antibiotics against all eight isolates of P multocida, against seven of nine isolates of H pleuropneumoniae and against the single strain of B bronchiseptica tested. Two field trials were carried out on a herd with a history of complicated enzootic pneumonia where the presence of Mycoplasma hyopneumoniae and P multocida had been established and subsequently the presence of H pleuropneumoniae was discovered. Feed containing tiamulin at 100 ppm combined with chlortetracycline at 300 ppm was given for seven days to pigs affected with pneumonia, and the results were compared with untreated controls and pigs receiving chlortetracycline at 300 ppm. There was a follow-up observation period of three weeks when all groups received unmedicated feed. During the medication period the combination treated groups showed a statistically significant increase in average daily weight gain of 156 g (20.4 per cent) and in feed conversion efficiency of 0.576 (20.8 per cent) and a numerical improvement in average disease score in comparison with the untreated controls. These improvements were approximately double those observed in the groups treated with 300 ppm chlortetracycline which showed improvements of 93 g (12.2 per cent) in average daily gain and 0.301 (10.9 per cent) in feed conversion efficiency. During the following three weeks most of the initial gains were lost, probably owing to the reinfection of the treated groups by the untreated controls.

Topics: Animal Feed; Animals; Anti-Bacterial Agents; Bacterial Infections; Chlortetracycline; Diterpenes; Drug Synergism; Drug Therapy, Combination; Microbial Sensitivity Tests; Pneumonia; Pneumonia of Swine, Mycoplasmal; Swine; Swine Diseases

The effects of tylosin tartrate and tiamutilin were examined in pneumonias induced experimentally in neonatal piglets with a homogenate of pneumonic pig lung, obtained from pigs with naturally acquired enzootic pneumonia. The homogenate contained mycoplasmas, including Mycoplasma hyopneumoniae (M suipneumoniae) and M hyorhinis, and certain bacteria and viruses. The experimental pneumonias generally resembled mycoplasmal pneumonia histologically but were complicated by aspiration pneumonia in some animals. both tylosin tartrate (50 mg/kg) and tiamutilin (10 mg/kg) administered orally twice daily for 10 days, beginning 14 days after intranasal infection, significantly reduced the incidence and severity of macroscopical pneumonic lung lesions. M hyopneumoniae could be isolated from the lungs of the unmedicated piglets, but not from drug-treated piglets. The numbers of M hyorhinis, Acholeplasma granularum, Haemophilus parasuis, Pasteurella multocida and P haemolytica in the lung tissue of the infected piglets were significantly reduced by drug therapy. The role of bacterial in the experimental infection appeared to be that of secondary invaders.

Topics: Animals; Anti-Bacterial Agents; Bacterial Infections; Diterpenes; Drug Therapy, Combination; Leucomycins; Pneumonia; Pneumonia of Swine, Mycoplasmal; Pneumonia, Aspiration; Pneumonia, Viral; Swine; Swine Diseases; Tylosin

Topics: Animals; Anti-Bacterial Agents; Diterpenes; Leucomycins; Mycoplasma; Mycoplasma Infections; Oxytetracycline; Pneumonia; Swine; Swine Diseases