Abstract

Introduction

Pinnipeds have a high incidence of lens diseases including lens luxation and cataract. All of the participating facilities have pinnipeds affected with these problems rendering many blind or requiring surgical lensectomy. In order to evaluate the risk factors associated with lens diseases in pinnipeds we created a questionnaire that included behavioral, environmental, medical, and genetic factors.

Materials and Methods

Descriptive analysis was performed in this initial phase of the questionnaire evaluation. Sixty six California sea lions, 4 seals, and 2 walruses from 6 facilities were included in the questionnaire. Ophthalmic examinations were performed on all animals by a veterinary ophthalmologist (CMHC except Denver zoo and SD Denver zoo).

Results

Twenty seven animals are females and 45 are males. The average age of all animals is 12.84 years. Fifty of 59 animals (84.75%) were raised in captivity and 15.25% (9/59) were beached. Sixty two of 72 animals (88.57%) live in salt water. Sixty six of 72 (97.06%) are not aggressive; 38.18% do not have a history of fighting while 61.82% have a history of fighting. Forty eight of 51 (94.12%) have no history of systemic disease, 3/51 (5.88%) have a history of systemic disease. Thirty nine of 69 (56.52%) do not have a history of ocular disease, 30 of 69 (43.48%) have a history of ocular disease. Seven of 47 (14.89%) have parents that were blind, the rest were unknown 40/47 (85.11%). Forty one of 72 (56.94%) do not have lens disease and 31/72 (43.06%) have lens disease. Forty eight of 66 (72.73%) are neutered while 16/66 (24.25%) are not. Sixty three of 68 (92.65%) have been at two or fewer facilities, 5/68 (7.35%) have been at 3 to 6 facilities. Pool corner shapes/textures include rocky (16/68, 23.53%), rounded (26/68, 38.24%), and straight (26/68, 38.24%). Overall pool shapes include bean (9/68, 13.24%), natural (8/68, 11.76%), rectangular (27/68, 39.71%), round (8/68, 11.76%), and square (16/68, 23.53%). Thirty five of 68 (51.47%) are show animals, 27/68 (39.71%) are display or off exhibit, 6/68 (8.82%) are both show and display animals. Forty nine of 51 (96.08%) are exposed to sun. Twenty six of 49 (53.06%) have cloth shade, 15/49 (30.61%) have canvas shade, and 8/49 (16.33%) have tarp shade. Sixty eight of 68 (100%) receive nutritional supplements.

Conclusions

Lens diseases including cataracts and lens luxations occur in both captive and wild pinnipeds. We found a high incidence of both in our initial evaluation of captive pinnipeds in the participating facilities. Cataracts and lens luxation have genetic, environmental i.e., sunlight, and systemic disease as potential predisposing factors in all species. In order to better determine the risk factors for these problems in pinnipeds, we designed the described questionnaire with input from all co-authors, and results will be correlated to lens disease in the final phase of this project.

Supported by the Columbus Zoo and Aquarium and The Ohio State University's Matching Research funds.