Echotextural evaluation of ultrasonographic images of the uterus in non-pregnant and pregnant Awassi ewes using computer-assisted image analysis

Abstract

The aim of this study is to determine how physiological changes occurring in the uterus during early pregnancy affect echotexture values by computer-assisted analysis of ultrasonographic images of the uterus in pregnant and non-pregnant ewes. It was also aimed to clarify the relationship between the echotextural parameters and progesterone (P₄) hormone in this period. A total of 40 Awassi ewes were used in the study, as Group 1 (n=20) not pregnant ewes, and Group 2 (n=20) pregnant ewes. Transrectal ultrasonography was applied on days 4, 7, 10, 13, 15, 16, and 17 after natural mating and the uterus tissue images were recorded. Blood samples were taken for the measurement of progesterone hormone. Measurements were taken on the uterus ultrasonographic images of the mean grayness value (MGV), homogeneity (HOM), and contrast (CON). In the statistical analyses of the data, two-way repeated measures ANOVA were examined with variance analysis and the Pearson test. It was found a time-related significant difference in the echotexture parameters within the groups of the pregnant and non-pregnant ewes in respect of the MGV, HOM, and CON values (P<0.05). The MGV and HOM values in all the days when measurements were taken after natural mating were significantly higher in the non-pregnant ewes compared to the pregnant group (P<0.001). The CON value was significantly higher in the pregnant ewes than the non-pregnant ewes in all days of measurement after natural mating (P<0.001). A time-related statistically significant difference was determined in the serum P₄ within the groups of pregnant and non-pregnant ewes (P<0.001) and it was higher in the pregnant ewes (P<0.001). A significant negative correlation was determined between P₄ and MGV, and between P₄ and HOM, and a significant positive correlation between P₄ and CON. In conclusion, it was found a significant difference between the pregnant and non-pregnant ewes in respect of the echotextural evaluation of the uterus and the measurement of P₄ hormone. In ewes farming, the early determination of pregnancy and early determination of ewes that are not pregnant gives the opportunity for repeat mating, and the evaluation of changes occurring in the uterus by computer-assisted image analysis can be used as an assistive method for providing additional nutrition in pregnant ewes.