Efficacy of a long-acting formulation of ceftiofur crystalline-free acid for the treatment of naturally occurring infectious bovine keratoconjunctivitis.
OBJECTIVE
To evaluate the efficacy of ceftiofur crystalline-free acid (CCFA) administered into the posterior aspect of an ear for treatment of corneal ulceration associated with naturally occurring infectious bovine keratoconjunctivitis (IBK).


METHODS
78 beef calves located at Sierra Foothills Field Station (SFS) and 52 calves located at a commercial dairy (CD). All calves were from 3 to 9 months old.


METHODS
At each site, calves were randomly allocated to 1 of 2 treatment groups by use of a block design determined by corneal ulcer size. A single dose of CCFA (6.6 mg of ceftiofur equivalents/kg, s.c.) was administered into the posterior aspect of a pinna. A second group of calves received a single dose of vehicle (0.03 mL/kg, s.c.; controls). Corneal ulcers were photographed, and clinical signs were assessed in calves every 3 to 4 days for 21 days.


RESULTS
A positive treatment effect was detected at SFS. Results at the CD were inconclusive because ulcer healing occurred rapidly in control and CCFA-treated calves. At SFS, treatment with CCFA resulted in shorter mean healing times, smaller corneal ulcer surface area measurements, amelioration of ocular discharge and photophobia, and a 50% increase in the percentage of calves healed by day 14. After adjustment for initial corneal ulcer size, treatment with CCFA resulted in a 4-fold increase in the odds of corneal ulcer healing by day 14, compared with controls.


CONCLUSIONS
A single dose of CCFA administered into the posterior aspect of a pinna had a positive treatment effect against naturally occurring IBK in calves with corneal ulcerations.
Department of Veterinary Medicine and Epidemiology, School of Veterinary Medicine, University of California, Davis, CA 95616, USA.
Erica L
EL
Dueger
Lisle W
LW
George
John A
JA
Angelos
Natalie S
NS
Tankersley
Kelsie M
KM
Luiz
Jonalee A
JA
Meyer
Ellen S
ES
Portis
Merlyn J
MJ
Lucas
D000818:Animals; D001837:Body Weights and Measures / Q000662:veterinary; D002140:California; D002417:Cattle; D002418:Cattle Diseases / Q000188:drug therapy*; D002511:Cephalosporins / Q000627:therapeutic use*; D003315:Cornea / Q000473:pathology; D007639:Keratoconjunctivitis, Infectious / Q000188:drug therapy*; D045828:Moraxellaceae Infections / Q000188:drug therapy / Q000662:veterinary*; D013997:Time Factors
D002511:Cephalosporins; C053503:ceftiofur