Characterization of progressive keratitis in Otariids

Abstract

'Otariid Keratitis' occurs in all populations of eared seals evaluated. A large-scale epidemiological study is ongoing to identify the risk factors that contribute to this disease. Exposure to chronic sunlight appears to be an important risk factor as shade diminishes clinical signs; animals kept out of sunlight the majority of the time have less severe clinical signs. Age may be important since exposure accumulates with aging. Progression of the disease is also associated with secondary opportunistic bacterial and fungal infections. The surface immune system may be imbalanced contributing to these infections and progression.

Incidence and management of ulcerative keratitis in a pinnipeds population under human care

“…The results confirmed the literature [1][2][3][4]. Comparing with other authors [5], a lower incidence of the phenomenon in our population resulted (46.6% versus 64.6% of individuals affected), but it is important to consider how in her study, Colitzalso includes individuals with localized corneal opacities and signs of ocular discomfort but without ulceration.…”

“…The oral doxycycline, in particular, can help for its antibiotic but also immunomodulatory effect, as it was also proven its ability to achieve adequate therapeutic concentrations in the tear film [6]. The N-acetylcysteine may help topical eye drops to penetrate through the thick tear film mucosal [1], while the use of platelet rich plasma (PRP) showed to be effective for the regeneration of the extensive and deep corneal ulcers [8][9][10] thanks to the presence of alpha-macroglobulin [7]. The use of eye drops hyperosmotic such as sodium chloride 5% or glucose 35% can be very useful in case of edema or corneal bubbles (Figure 2), or sub-epithelial stromal, since these substances are able to improve the transparency and prevent further damage to the epithelium [11].…”

“…of the "risk factors" such as the ultraviolet radiation from the sun.The ability of UV rays from damaging all corneal layers has been widely proven [1,4,5,11]. Another clinical signis the reduction of the signs of ocular discomfort, such as blepharospasm, when the color and the material used in the construction of the tanks limiting the production of reflections and glare.…”

“…To prevent oxidative damage caused by UV rays, as well as provide shaded areas where the animals can take shelter from the sun, you can use rich dietary supplements of antioxidants [8]. Finally,the water quality: the salinity, the concentration of nitrogen compounds, the temperature, the type of disinfectant agents used and the concentration of coliform organisms have all been recognized as possible factors able to influence the onset and evolution of corneal ulcers in pinnipeds, and are studied at present [1]. doi: 10.7243/2054-3425-5-1…”

“…Eye diseases are quite common in pinnipeds, both in wild or under human care population [1][2][3][4]. Among the ocular disorders more frequent in these marine mammals there are certainly those of the cornea, with a wide range of clinical presentations from keratitis localized and not complicated to more or less deep or infected ulcers [5,6].…”