Ultrasound is a powerful tool for the evaluation of morphological characteristics of the ewes udder and teats. It was studied the size of mammary cistern in ewes of nine genotypes (purebred Improved Valachian (IV), purebred Tsigai (T), purebred Lacaune (LC) and their crosses of IV and T with specialized dairy breeds Lacaune and East-Friesian (EF). Data were evaluated using restricted maximum likelihood (REML) methodology and MIXED procedure (SAS/STAT). The effect of genotype showed the highest influence (P