Brown M H, Brightman A H, Fenwick B W, Rider M A
Veterinary Referral Centre, Little Falls, NJ 07424, USA.
J Vet Intern Med. 1998 Jul-Aug;12(4):259-66. doi: 10.1111/j.1939-1676.1998.tb02120.x.
The economic impact of infectious bovine keratoconjunctivitis (IBK) warrants continued investigation of the mechanisms by which Moraxella bovis survives on and colonizes the corneal surface. Virulent strains of M bovis produce hemolysin and exhibit different plasmid profiles than nonvirulent strains. Interactions among host, environment, vector, season, and concurrent infection influence the prevalence of IBK. Mycoplasma sp. or infectious bovine rhinotracheitis virus may enhance or hasten the disease process. The manifestations of IBK may range from mild conjunctivitis to severe ulceration, corneal perforation, and blindness. Treatment of IBK is dictated by economic considerations, intended animal use, and feasibility of administration. Antibiotic therapy is aimed at achieving drug concentrations in tears to meet or exceed the minimum inhibitory concentration for prolonged periods. At present, IBK is not a preventable disease. Affected animals must be separated from the herd and vector control vigorously instituted. Carrier animals must be identified and removed from the herd. Vaccination trials have been unsuccessful because of pili antigen cross-reactivity, variable strains, and uncontrolled environmental factors. Recent investigations have determined that M bovis may utilize host iron sources via iron-repressible outer membrane proteins and siderophores for growth. Elucidation of normal defense mechanisms of the bovine eye may lead to new strategies to enhance the immune response against M bovis.
传染性牛角膜结膜炎（IBK）的经济影响促使人们继续研究牛莫拉菌在角膜表面存活和定殖的机制。牛莫拉菌的强毒株会产生溶血素，并且与无毒株相比呈现出不同的质粒图谱。宿主、环境、媒介、季节以及并发感染之间的相互作用会影响IBK的流行率。支原体属或传染性牛鼻气管炎病毒可能会加剧或加速疾病进程。IBK的表现可能从轻度结膜炎到严重溃疡、角膜穿孔和失明不等。IBK的治疗取决于经济因素、动物预期用途以及给药的可行性。抗生素治疗旨在使泪液中的药物浓度长时间达到或超过最低抑菌浓度。目前，IBK是一种不可预防的疾病。必须将患病动物与牛群隔离，并大力实施媒介控制。必须识别并清除带菌动物。由于菌毛抗原交叉反应、菌株变异以及环境因素无法控制，疫苗接种试验一直未成功。最近的研究已确定，牛莫拉菌可能通过铁抑制外膜蛋白和铁载体利用宿主铁源进行生长。阐明牛眼的正常防御机制可能会带来增强针对牛莫拉菌免疫反应的新策略。
