The morphology and cell structure of some nuclei in tuberal region of bison bonasus.

The topography, shape and cell structure of the ventromedial, dorsomedial and infundibular nuclei in aurochs hypothalamus were studied on the basis of standard histological preparations. These nuclei are uniform cell bands. Nucleus infundibularis is the longest centre in tuberal region and enter the mamillary area. Its posterior part has maximum size. The ventromedial nucleus is outlined and developed best. It is typical ring-shaped in anterior half of its length. The dorsomedial nucleus is developed best in its middle sector. There is no clear border between Dm and Ni. Comparing the topography and structure of Ni, Vm and Dm of bison with analogic centres of other mammals, it was found that have more common features with these nuclei in breeding domestic animals.