[The karyotype and character of chromosome bands in mountain sheep in Czechoslovakia].

Thirty-one moufflon (Ovis musimon) coming from eight localities in Bohemia and Moravia were examined. All animals had a diploid number of chromosomes without any numerical or structural aberrations from the standard set. On the basis of G-banding, all chromosomes were arranged into homologous pairs. C-banding was used to prove the localization of constitutive heterochromatin in the centromeric regions of the majority of chromosomes. Nucleolus organizers, demonstrated by means of A-staining, were located telometrically on the chromosomes in three big two-arm pairs and two acrocentric pairs. The number of active nucleolus organizers in individual cells ranged from 2 to 7. When these results were compared with the published data on the karyotype of sheep, the two forms were found to have much in common. It can be supposed that the karyotypes of moufflon and domestic sheep differ in the frequency of the occurrence of Ag-positive sections with nucleolus organizers.