Blackman N L, Cheetham K, Blackmore D K
Res Vet Sci. 1986 Mar;40(2):252-4.
Using methylene blue boli, injected via an intracardiac catheter, the blood supply to the brain in two one- to 10-day-old calves and three adult sheep was studied during and after severance of the common carotid arteries and jugular veins. Passage of dye through cerebral vessels could not be observed in the exposed cerebrum of sheep after bilateral severance of major blood vessels. When vessels were severed on one side only, the passage of dye was noted for at least 53 seconds. In calves, after bilateral severance, sequential boli of dye could be detected passing through the cerebral vessels for more than 100 seconds. These results provide an explanation and support for the belief that there are major differences in the onset of insensibility between sheep and calves subsequent to severance of the common carotid arteries and jugular veins. The differences in blood supply to the brain which were demonstrated could be accounted for by differences in the blood supply to the brain by the vertebral artery in sheep and cattle. The effects of slaughter on the blood supply to the eye are discussed as a possible explanation of the disparity between results of studies in this general field which have used retinal responses in their investigations and those which have not.
通过心内导管注射亚甲蓝团注，研究了两只1至10日龄犊牛和三只成年绵羊在切断颈总动脉和颈静脉期间及之后的脑供血情况。在双侧切断主要血管后，在暴露的绵羊大脑中未观察到染料通过脑血管。仅在一侧切断血管时，染料通过至少持续53秒。在犊牛中，双侧切断后，可检测到连续的染料团注通过脑血管超过100秒。这些结果为以下观点提供了解释和支持，即切断颈总动脉和颈静脉后，绵羊和犊牛失去知觉的起始存在重大差异。所显示的脑供血差异可归因于绵羊和牛椎动脉对脑供血的差异。讨论了屠宰对眼供血的影响，作为对该一般领域中使用视网膜反应进行研究的结果与未使用视网膜反应进行研究的结果之间差异的一种可能解释。
