Ocular Surface Disease in Rodents (Guinea Pigs, Mice, Rats, Chinchillas)

Abstract

This article discusses the clinical appearance, differential diagnoses, and treatment considerations of corneal disease in the most common domesticated species of rodent: mouse, rat, chinchilla, and guinea pig. Many corneal diseases are related to inbred strains of either research or pet rodents. Diseases are complicated by husbandry and treatment-related challenges in this small, social species. This article is broken down by species, first discussing normal anatomy, then discussing commonly encountered diseases, and concluding with treatment considerations.

Keywords: Chromodacryorrhea; Conjunctivitis; Cornea; Dystrophy; Keratoconjunctivitis sicca; Scurvy.

Fig. 1

Guinea pig undergoing Schirmer tear test. Guinea pigs have been shown to have a remarkably insensitive cornea relative to other domesticated species, and little to no reflex tearing.

Fig. 2

Infected corneal ulcer in a guinea pig. This is a disease process in which guinea pigs would benefit from additional supplementation of vitamin C for normal physiology and also for its anticollagenolytic properties.

Fig. 3

Ocular pathology associated with mouse models of Sjögren syndrome. Here one can see disease ranging from a clear corneal with mild discharge, to blepharospasm and keratitis, all the way to a stromal corneal ulcer with secondary infection.

Fig. 4

Severe example of corneal dystrophy in a laboratory mouse. This individual was considered comfortable (no blepharospasm) and clinically acceptable as a research subject.

Fig. 5

Another example of severe corneal dystrophy, this time in a laboratory rat. Just like the mouse example, no blepharospasm was exhibited by this individual.