Herbert J, Stacey P M, Thorpe D H
J Endocrinol. 1978 Sep;78(3):389-97. doi: 10.1677/joe.0.0780389.
The breeding seasons of two groups of pinealectomized ferrets and one group of blind ferrets, with appropriate controls, were observed for up to 5 years after the operations. All animals showed recurrent breeding seasons. Both pinealectomized and blind animals became increasingly asynchronous after the first season, but showed no evidence of a free-running, endogenous circannual periodicity nor of synchronization to light or other environmental cues.
对两组松果体切除的雪貂和一组失明雪貂及其相应对照组的繁殖季节进行了长达5年的观察，观察期自手术开始。所有动物均表现出繁殖季节的反复出现。松果体切除的雪貂和失明雪貂在第一个季节后变得越来越不同步，但没有证据表明存在自由运行的内源性年周期节律，也没有同步到光照或其他环境线索的迹象。
