Characteristics of changes in the structures of the anterior eye of rabbits at acute opisthorchosis and paracoenogonymosis

Abstract

The purpose of the research is studying changes in the structures of the anterior eye of rabbits at acute opisthorchosis and paracoenogonymosis in experiment.Materials and methods. The studies were performed on sexually mature male rabbits. The first group consisted of animals infected with 50 metacercariae Opisthorhis felineus (Rivolta, 1884) (n = 3), and the second consisted of animals infected with 50 metacercariae Paracoenogonimus ovatus (Katsurada, 1914) (n = 3). The animals from the third group were control (n = 3). The study at opisthorchosis was performed at 1, 2, 3, 4 and 5 weeks after infection, and the study at paracoenogonymosis was only performed at 1 and 2 weeks in connection with rapidly proceeding infection. These groups were compared within 1 and 2 weeks and according to specific changes. The clinical study included the upper and lower eyelids turned outwards in animals, and examination of the conjunctival surface of the eyelids, epicanthus (third eyelid), cornea, limbus and sclera of the eyeball, and eyelash less edge of the eyelids at all periods of observation. The measurements were carried out with a millimeter ruler along the longest part of the formation. The data were processed statistically by calculating the arithmetic mean (M) with the standard error of mean (σ) using the Microsoft Excel 2007 software package, and changes in characteristics were assessed at follow-up by the Wilcoxon rank sum test.Results and discussion. In the acute phase of opisthorchosis, the structures of the anterior eye are damaged, which occurs after the first week of infection in the form of allergic conjunctivitis, episcleritis. We found follicular formations in the upper eyelid, in the outer corner of the eye with further synulosis by the 5th week, and vascular enhancement of the upper eyelid. Conjunctival and corneal changes a month later were of the type of trachomatous pannus with conjunctival hyperemia of both eyelids, edema, and reddening of the free eyelash less edge. The infection by P. ovatus showed no follicular formations or eyelid edema for two weeks. Thus, at opisthorchosis, we observed the phenomena of combined pathology of the visual organ with a specific component for which an independent name can be distinguished, specific parasite-associated ophthalmitis.