Sensor Jennifer D, Suydam Robert, George John C, Liberman M C, Lovano Denise, Rhaganti Mary Ann, Usip Sharon, Vinyard Christopher J, Thewissen J G M
Department of Anatomy and Neurobiology, Northeast Ohio Medical University, Rootstown, Ohio, 44240.
Department of Wildlife Management, North Slope Borough, Barrow, Alaska, 99723.
J Morphol. 2015 Dec;276(12):1455-66. doi: 10.1002/jmor.20434. Epub 2015 Sep 3.
With the increase of human activity and corresponding increase in anthropogenic sounds in marine waters of the Arctic, it is necessary to understand its effect on the hearing of marine wildlife. We have conducted a baseline study on the spiral ganglion and Rosenthal's canal of the cochlea in beluga whales (Delphinapterus leucas) as an initial assessment of auditory anatomy and health. We present morphometric data on the length of the cochlea, number of whorls, neuron densities along its length, Rosenthal's canal length, and cross-sectional area, and show some histological results. In belugas, Rosenthal's canal is not a cylinder of equal cross-sectional area, but its cross-section is greatest near the apex of the basal whorl. We found systematic variation in the numbers of neurons along the length of the spiral ganglion, indicating that neurons are not dispersed evenly in Rosenthal's canal. These results provide data on functionally important structural parameters of the beluga ear. We observed no signs of acoustic trauma in our sample of beluga whales.
随着人类活动的增加以及北极海域人为声音相应增多，有必要了解其对海洋野生动物听力的影响。我们对白鲸（白鲸属）的耳蜗螺旋神经节和罗森塔尔管进行了一项基线研究，作为对听觉解剖结构和健康状况的初步评估。我们给出了关于耳蜗长度、螺旋圈数、沿其长度的神经元密度、罗森塔尔管长度和横截面积的形态测量数据，并展示了一些组织学结果。在白鲸中，罗森塔尔管并非横截面积相等的圆柱体，而是其横截面积在基部螺旋圈的顶端附近最大。我们发现沿螺旋神经节长度的神经元数量存在系统性变化，这表明神经元在罗森塔尔管中分布并不均匀。这些结果提供了白鲸耳朵功能上重要的结构参数数据。在我们的白鲸样本中，未观察到声学创伤的迹象。
