Estimation of gestational age in Shami goats based on transabdominal ultrasonographic measurements of fetal parameters

Abstract

Estimated gestational age is essential for breeding farm animals because pregnant females require special care and nutrition, which varies according to gestation. The study aimed to estimate the gestational age of Shami does by transabdominal ultrasonographic measurement of fetal parameters. Thirty-three Shami does aged 2-2.5 years with confirmed conception dates were used. The does were examined in a standing position using a transabdominal 3.5 MHz convex sector probe of real-time ultrasonography. The does were examined weekly starting on 21 days of pregnancy until parturition. Measurements of the fetal parameters that include; the crown-rump length, head diameter, chest diameter, trunk diameter were obtained from the ultrasonographic images using the software Screen Calipers. Results showed that the gestational sac and embryos were observed first on 21 and 35 days of pregnancy. The litter size of pregnant does range between two and three kids. Crown-rump length ranged between 24.68±1.32 - 71.71±1.84 mm on 41-60 days. The head diameter was 15.63±0.82 - 45.04±0.92 mm on 41-120 days. Chest diameter was 11.52±0.84 - 56.35±0.93 on 51-110 days, and trunk diameter was 10.69±0.85 - 57.38±0.85 mm on 41-130 days of gestation. The highest positive correlations were obtained between the gestational age chest diameter (r=0.935), crown-rump length (r=0.917), head diameter (r=0.917) and trunk diameter (r=903). In conclusion, transabdominal ultrasonography is a practical method for pregnancy diagnosis and embryo monitoring in Shami goats. Also, it is reliable to estimate gestation age starting on 41 days of pregnancy. The chest diameter was the best fetal parameter, but trunk diameter can be used for the longest period to estimate the gestational age of Shami goats.