Morphological udder traits have recently become of greater interest from farmers to researchers. In dairy ewes, the udder is very important due to its physiological and conformational characteristics. External udder traits were measured in ewes ( Ovis aries
L.) of nine genotypes (355 ewes) created of the basis of Improved Valachian (IV), Tsigai (T), and Lacaune (LC) breeds (six traits; 1185 data for each trait) during the milking period 2002-2008. Udder measurements were assessed for: udder length (UL), udder width (UW), rear udder depth (RUD), cistern depth (CDE), teat length (TL), and teat angle (TA). Data were processed by restricted maximum likelihood (REML) methodology using a MIXED procedure from the SAS statistical package. All studied parameters were influenced by the genotype (P < 0.001), many of them also by the effect of parity and lactation stage. The exactly detected UL, UW and RUD during the lactation and with the age of ewes expand gradually (P < 0.001). Teat length was greater in older ewes (expanding, with the parity). Indicator TA during lactation worsened. Crosses with 25 to 75% share of genetic dairy breeds (in particular with LC, to a lesser extent ‘East Friesian’ - EF) were in most cases larger than the udder cisterns of purebred ewes T and IV. Purebred LC had the largest udders, with the largest cisterns. In conclusion, crosses with specialized dairy breeds have more suitable udders for machine milking than purebred default breeds (T, IV, LC) and are suitable for machine milking.