Fundus Imaging via Infrared Camera without Mydriatics in Holstein Calves

Abstract

This study aimed to record the ocular fundus images of healthy Holstein calves under field conditions. The fundus of 34 eyes of healthy 17 Holstein calves was examined with a fundus camera, which does not require mydriatics, as it has been designed especially for animals and provides imaging with infrared light. The findings showed that the green-yellow tapetal zone was dominant in all calves, the optic disc was oval, and the number of primary arteries and veins originating from the center varied between 4 and 5. The vascular pattern was holangiotic. A remnant of the hyaloid artery (Bergmeister’s papilla) was detected as a gray dot in the middle of the disc. It was noted that the non-tapetal area was homogeneous, brown-black, and rich in choroidal vascular structure. Imaging the ocular fundus is essential in diagnosing some systemic and hereditary diseases in farm animals. However, herd-based ophthalmoscopic screening in farm animals is difficult under field conditions. By using this portable fundus camera, fundus examination can be performed easily under field conditions without taking the animals to the hospital. The standard ophthalmoscopic fundus images of healthy Holstein calves presented in this study will contribute to the literature.