Clinical effectiveness of enrofloxacin 100 mg/mL injectable solution for the treatment of acute anaplasmosis in cattle caused by Anaplasma marginale

  • Douglas D. Shane Bayer U.S. LLC, Animal Health, 12707 Shawnee Mission Parkway, Shawnee, KS 66216
  • Kelly F. Lechtenberg Midwest Veterinary Services, Inc., 1290 County Rd. M, Oakland, NE 68045
  • Jon Seagren Midwest Veterinary Services, Inc., 1290 County Rd. M, Oakland, NE 68045
  • Ronald K. Tessman Bayer U.S. LLC, Animal Health, 12707 Shawnee Mission Parkway, Shawnee, KS 66216
  • Vijaya Krishna Singu Central States Research Center, Inc., 1290 County Rd. M, Oakland, NE 68045
  • Yingying Wang Bayer U.S. LLC, Animal Health, 12707 Shawnee Mission Parkway, Shawnee, KS 66216
  • Johann Coetzee Department of Anatomy and Physiology, Kansas State University College of Veterinary Medicine, 228 Coles Hall, 1620 Denison Ave, Manhattan, KS 66506
  • Kathryn E. Reif Center of Excellence for Vector-Borne Diseases, Department of Diagnostic Medicine/Pathobiology, Kansas State University College of Veterinary Medicine, K-221 Mosier Hall, 1620 Denison Ave, Manhattan, KS 66506
Keywords: Anaplasma marginale, anaplasmosis, treatment, enrofloxacin, bovine

Abstract

Anaplasma marginale is a gram-negative rickettsial pathogen that can cause clinical anemia and death in cattle. The objective of this study was to evaluate the effectiveness of enrofloxacin (ENR) 100 mg/mL at a single subcutaneous dose of 5.7 mg/lb (12.5 mg/kg) for treatment of acute anaplasmosis (ANA) in mature beef cows (n=67). Following intravenous inoculation with A. marginale-infected blood, cattle were monitored for clinical signs of ANA. Upon meeting case criteria, cattle were randomly assigned to receive ENR or saline (SAL). Treatment success, defined as 28 d post-treatment survival and resolution of abnormal clinical scores, was 81.8% (27/33) and 44.1% (15/34) (P=0.0032) for ENR and SAL treated cows, respectively. Mortality was 47% (16/34) and 3% (1/33) in SAL and ENR, respectively (P=0.0027). Packed cell volume at 7, 14, 21, and 28 d post-treatment was significantly greater in ENR compared to SAL (P<0.05). In this study, ENR improved treatment success compared to SAL, reduced ANA mortality, and maintained greater packed cell volumes post-clinical signs compared to SAL. Extra-label use of fluoroquinolones in food animals is prohibited in the United States, but ENR (Baytril® 100-CA1) was recently conditionally approved for treatment of ANA.

Published
2020-02-01
How to Cite
Shane, D. D., Lechtenberg, K. F., Seagren, J., Tessman, R. K., Singu, V. K., Wang, Y., Coetzee, J., & Reif, K. E. (2020). Clinical effectiveness of enrofloxacin 100 mg/mL injectable solution for the treatment of acute anaplasmosis in cattle caused by Anaplasma marginale. The Bovine Practitioner, 54(1), 51-57. https://doi.org/10.21423/bovine-vol54no1p51-57
Section
Articles