The clinical efficacy of chloramphenicol eye drop to treat the pinkeye in Holstein dairy calves

Objectives: Moraxella bovis causes pink eye in cattle. It is an infectious and highly contagious disease. The initial clinical signs are swell­ing and redness of the conjunctiva, excessive tearing. Affected animals have a decreased appetite and moderate fever. Corneal disorders such as pannus formation and lesions are important consequences of pink eye. There are several drugs and therapeutic regimens to resolve pink eye in cattle, but the present study was conducted to evaluate the effects of chloramphenicol eye drop to treat this problem. Materials methods: Ten Holstein dairy calves (2-3 months old) affected with pinkeye were randomly assigned into 2 equal groups in a dairy farm. In Group 1, calves received oxytetracycline 5% (5 mg/kg, daily) and flunexine meglumine 5% (2.2 mg/kg) until 3 days. In Group 2, same drugs plus chloramphenicol eye drop (2 times daily) were administered until 3 days. A corneal lesion healing of affected animals was monitored during treatments and resolution of corneal opacity was our landmark to evaluate improvement rate in patients.Results conclusions: The corneal lesions of animals in Group 2 were improved sooner than other group. Researchers mentioned that the broad spectrum antibiotics are potentially active against Moraxella bovis. Several routs of administrations of antibiotics such as intravenous, intramuscular and intraconjunctival are also suggested. The administration of antibiotic as ophthalmic drop can active directly against microorganisms in the site of infection. Furthermore, the combination therapy has benefits rather than the use of one antibiotic; hence, animals in Group 2 were treated earlier. Local application of antibiotics to the eye often gives rapid activity against Moraxella bovis and improving corneal lesions lesions are occurred subsequently. Finally, it can be concluded that combination therapy and the use of antibiotics in the site of infection are the important therapeutic regimens to resolve pink eye.