tilmicosin and Respiratory-Syncytial-Virus-Infections

Severe respiratory disease, associated with seroconversion to bovine respiratory syncitial virus (BRSV), caused the death of two cattle and necessitated antibiotic treatment of 70 calves (rectal temperature of 39.6 degrees C or greater) from a group of 96 (73%) during an 8-day period. Tilmicosin injection resulted in a reduction in median rectal temperature from 40.3 degrees C to 39.2 degrees C and 39.0 degrees C for the first and second days after treatment. The rectal temperature was 39.5 degrees C or lower in 72% (48 of 67) and 96% (64 of 67) of cattle 1 and 2 days after tilmicosin treatment, respectively. Ten cattle were re-treated with tilmicosin 6 to 16 days after the first treatment. Our study demonstrated that bovine respiratory syncytial virus infection could cause severe respiratory disease in a beef herd that had no previous history of BRSV-related disease. Secondary bacterial invasion after BRSV infection was controlled effectively by tilmicosin treatment but repeat antibiotic treatments were occasionally necessary due to bacterial re-infection of the respiratory tract.

Topics: Animals; Anti-Bacterial Agents; Anti-Inflammatory Agents, Non-Steroidal; Body Temperature; Cattle; Cattle Diseases; Clonixin; Disease Outbreaks; Macrolides; Respiratory Syncytial Virus Infections; Scotland; Time Factors; Treatment Outcome; Tylosin

A severe outbreak of undifferentiated respiratory disease affecting 119 of 144 (82.6 per cent) two- to five-month-old housed beef calves was studied by monitoring their clinical signs and rectal temperatures daily or every second day for two months. New cases of respiratory disease, which were first identified three weeks after the calves were housed, occurred over a period of 29 days. The cause of the outbreak was not conclusively determined although 20 per cent of the calves sampled showed serological evidence of recent infection with bovine respiratory syncytial virus and parainfluenzavirus 3. Seventeen of 61 calves (27.9 per cent) which were treated with tilmicosin had to be treated again, compared with nine of 58 calves (15.5 per cent) which were treated with both tilmicosin and flunixin meglumine and did not need further treatment, but this difference was not statistically significant.

Topics: Animal Husbandry; Animals; Anti-Bacterial Agents; Anti-Inflammatory Agents, Non-Steroidal; Cattle; Cattle Diseases; Clonixin; Disease Outbreaks; Drug Therapy, Combination; Infectious Bovine Rhinotracheitis; Macrolides; Meat; Parainfluenza Virus 3, Human; Pasteurellosis, Pneumonic; Respiratory Syncytial Virus Infections; Respiratory Syncytial Virus, Bovine; Respiratory Tract Diseases; Tylosin; United Kingdom