Comparison of ceftiofur crystalline free acid to tilmicosin for metaphylactic treatment of calves at risk for bovine respiratory disease

Efficacy of metaphylactic ceftiofur crystalline free acid (CCFA) or tilmicosin phosphate (TIL) on performance and health of newly received calves at risk for bovine respiratory disease (BRD) was compared. Crossbred bull (n=39) and steer (n=264) calves (initial BW=464 +/- 27.7 lb (211 +/- 12.6 kg)) were received on 3 dates. Calves were stratified to pens by castrate status and BW. Pens were assigned randomly to single-dose antimicrobial metaphylaxis: (1) CCFA or (2) TIL. No differences (P greater than or equal to 0.23) in average daily gain were observed between metaphylactic treatments. Morbidity (calves treated atleast once for BRD) rates were 19.9 and 15.1% (P=0.13) for calves in the CCFA and TIL groups, respectively. Calves treated for clinical BRD after metaphylactic treatment with CCFA were 2.09 (95% confidence interval=(1.01, 4.32)) times more likely to be retreated once for BRD. Similarly, cattle treated for BRD after metaphylactic treatment with CCFA were 5.63 (95% confidence interval=(1.43, 22.19)) times more likely to be retreated twice for BRD. Antibiotic cost was $5.61/calf lower in the TIL group compared to calves in the CCFA group (P less than or equal to 0.05). Based on these results, metaphylactic treatment with TIL was more cost-effective and efficacious in reducing subsequent antibiotic treatments than CCFA.