Review on Infectious Bovine Keratoconjunctivitis and its Economic Impacts in Cattle

Abstract

Infectious bovine keratoconjunctivitis is one of the most common eye diseases of cattle and is of major eco-nomic importance in the world. It is a bacterial infection of the eye that causes inflammation and in severe cases temporary or permanent blindness. In cattle, the gram-negative bacterium Moraxella bovis is regarded as the main cause of the disease that affects cattle of all ages and occurs worldwide. Also, Moraxella bovoculi and a range of other bacteria, viruses, and environmental conditions seem to be involved. Moraxella bovis has several pathogenic mechanisms; however, only two, pili and the secretion of a β-hemolytic cytotoxin, have been determined to cause clinical disease. The pili allow the bacteria to attach to the dark cells of the corneal epithelium. The hemolysin is a pore-forming toxin that lyses corneal epithelial cells leading to ulceration and causes lysis of bovine leukocytes. The virulence of Moraxella bovis is influenced by both host and environmental factors. It is one of the examples of the diseases that may cause production losses in both dairy and beef farms in many countries. The economic impact of the disease is significant due to its high contagious nature. Most cattle producers are familiar with this disease but may not know how to best treat it and minimize its spread within the herd. The cost and time used in treating infected cattle adds to the economic losses. The best strategies to prevention and control of an outbreak are maximizing the herd’s immune status, minimizing the concentration of the Moraxella bacteria, and maintaining as irritant-free environment as possible. Treatment decisions are influenced by numerous factors such as effectiveness of the drug selected, cost, labor availability, withholding times, facilities, and availability of veterinary support. Vaccines are partially protective and cannot be completely relied upon to prevent the disease. Coming up with one solution is difficult because of all the contribution factors. Therefore, isolation and a swift reaction are keys in reducing the spread of the disease.