Cataracts in a laboratory colony of ferrets.

Cataracts were found by use of slit-lamp biomicroscopy in two genetically unrelated ferret populations (A and B). When they were initially examined at the age of 11 to 12 months, 34 of 73 ferrets (46.6%) in population A had lens opacities, which could be categorized into one of three groups. Group-1 ferrets (n = 25) manifested a continuum of lens changes ranging from fine, multifocal, punctate opacification of the superficial posterior lens cortex (n = 3), to changes in both the anterior and posterior cortex (n = 13), to immature (n = 1), or mature/hypermature cataracts (n = 8). Group-2 ferrets (n = 7) had bilateral microphthalmia and cataracts. Group-3 ferrets (n = 2) had minor lens changes involving the nucleus or cortex that were not typical of either group 1 or 2. By the age of 18 months, 41 of the remaining 42 animals in population A had developed fine, multifocal, punctate opacities of the posterior cortex. In group-1 animals, histologic changes in the lens ranged from several 80 x 40-microns, punctate, spheroidal lesions in the posterior cortex, to posterior migration of the lens epithelium, Morganian granules, and a complete mature/hypermature cataract. One group-2 ferret had microphthalmia, filling of the lens capsule with a cell-poor, periodic acid-Schiff stain-positive membranous material, and retinal detachment. Population B consisted of 15 adult and 47 6-month-old juvenile ferrets. Eleven adults had multifocal, fine, punctate, posterior cortical opacities, and one adult had a nuclear cataract.(ABSTRACT TRUNCATED AT 250 WORDS)