Wang Hsiao-Hui, Gallagher Shannon K, Byers Stacey R, Madl James E, Gionfriddo Juliet R
Department of Biomedical Sciences, Colorado State University, Fort Collins, CO, 80523, USA.
Vet Ophthalmol. 2015 Jan;18(1):35-42. doi: 10.1111/vop.12131. Epub 2013 Dec 10.
To investigate the distribution of retinal ganglion cells (RGCs) and visual acuity in alpacas (Vicugna pacos) through Brn-3a immunofluorescent labeling.
Five eyes from four healthy alpacas with normal ophthalmic examination findings were included in the study. The axial length of the globes was measured before fixation. All five retinas were treated with Brn-3a antibodies to label RGCs. Images taken with a fluorescent microscope were used for RGC counting. RGC density maps were reconstructed by computer software. Visual acuity was estimated based on the results of peak RGC density and ocular anatomical parameters.
The reconstructed retinal maps from Brn-3a labeling showed a horizontal streak across the retinal meridian superior to the optic nerve head with a temporal, upward extension. The highest RGC densities were in the temporal retinas. The maximal visual acuity was located in the temporal retina and was estimated to range between 12.5 and 13.4 cycles per degree.
Alpacas have a horizontal streak across the retinal meridian superior to the optic disk with a temporal, upward extension based on the Brn-3a labeling of RGCs. The maximal visual acuity was located in the temporal retina. The reconstructed retinal maps indicate the RGC topography of alpacas is similar to that of other herbivores, but is different from that of dromedary camels.
通过Brn-3a免疫荧光标记研究羊驼视网膜神经节细胞（RGCs）的分布及视力情况。
本研究纳入了4只眼科检查结果正常的健康羊驼的5只眼睛。在固定眼球前测量眼轴长度。所有5只视网膜均用Brn-3a抗体处理以标记RGCs。用荧光显微镜拍摄的图像用于RGC计数。通过计算机软件重建RGC密度图。根据RGC密度峰值和眼部解剖参数结果估算视力。
Brn-3a标记重建的视网膜图显示，在视神经乳头上方的视网膜子午线上有一条水平条纹，并向颞侧向上延伸。RGC密度最高的部位在颞侧视网膜。最大视力位于颞侧视网膜，估计范围为每度12.5至13.4周。
基于RGCs的Brn-3a标记，羊驼在视神经盘上方的视网膜子午线上有一条水平条纹，并向颞侧向上延伸。最大视力位于颞侧视网膜。重建的视网膜图表明，羊驼的RGC地形图与其他食草动物相似，但与单峰骆驼不同。
