Spontaneous ophthalmic lesions in young Swiss mice.

摘要: BACKGROUND AND PURPOSE Outbred mice are frequently used in toxicity evaluation. Due to their small size, ophthalmologic examination of such animals is difficult with regard restraint and use instruments designed for human medicine. The clinical appearance incidence spontaneous ophthalmic lesions should be helpful selecting studies allow distinction between intercurrent ocular changes those attributable drugs or chemicals. METHODS Pretest examinations about 3,000 4- 5-week-old Swiss mice, Crl:CD1 (ICR)BR, conducted 1995 1996, provided information incidence. Eye evaluations were performed after pupil dilatation (0.5% tropicamide instillation), using indirect ophthalmoscopy, when indicated, a portable slit lamp. RESULTS Lenticular opacities heterogeneity/prominence the most common findings (up 19%) anterior segment. Abnormalities cornea iris detected up 4% mice. Hyaloid artery remnant, as well isolated cases floating bodies hemorrhage, was observed vitreous 12 17% Approximately 2 had colobomatous fundus, retinal fold, atrophy. A few chorioretinal atrophy, abnormal pattern vasculature. Remaining consisted incomplete palpebral fissure, microphthalmia, exophthalmia, scleral mass. CONCLUSIONS severity condition interference examination, affected eliminated from experimental studies. Hence, pretest indicated safety-assessment