The effectiveness of topically applied
furazolidone (FZ) or parenterally administered
oxytetracycline (OTC) for treatment of infectious bovine
keratoconjunctivitis was determined in a field study. Between June 13 and Aug 6, 1985, a study was conducted on a ranch in northern California. Eyes of Hereford calves (n = 103) were examined 3 times each week for 7 weeks. After daily examinations on June 13 and 14, calves were allotted randomly to 3 groups. On June 17, calves (that had corneal
ulcers) of groups 1 (n = 35) and 2 (n = 35) were treated with OTC and FZ, respectively. Treatments were administered again only if new
ulcers were observed, if an existing
ulcer worsened, or if a healed
ulcer recurred. Calves of group 3 remained untreated (controls). Corneal
ulcers developed in 35 of the FZ-treated calves, in 33 of the OTC-treated calves, and in 33 of the untreated calves.
Corneal perforations were observed in 3 untreated and 2 FZ-treated calves but were not observed in any OTC-treated calves.
Panophthalmitis developed in one eye of an untreated calf. Corneal
ulcers in the OTC-treated calves were smaller and healed more rapidly than did corneal
ulcers in calves of the other groups. By the 22nd day of the study (July 3), the number of OTC-treated calves with corneal
ulcers was less than that of the other 2 groups. Calves of the OTC treatment group had the fewest multiple
corneal ulcer recurrences, but calves of all 3 groups had a similar number of single
corneal ulcer recurrences.(ABSTRACT TRUNCATED AT 250 WORDS)