Estimation of Gestational Age by Biometric Analysis of Embryonic and Foetal Development Using Transrectal Ultrasonography in Gaddi Ewes

The study evaluated embryonic and foetal biometry characters to predict the gestational age in Gaddi ewes using transrectal ultrasonography. Eight ewes were monitored sequentially from day 25 to 75 post mating at 10 days intervals. Biometric characters, including gestation sac diameter (GSD), amniotic sac diameter (ASD), crown-rump length (CRL), biparietal diameter (BPD) and abdominal diameter (AD) were measurable from day 25, while umbilical cord diameter (UCD), placentome diameter (PD), heart length (HL) and heart width (HW) were measured from day 35. All characters had significant (P<0.05) increase throughout the gestation. BPD was identified as the most accurate predictor of gestational age (R² = 0.979), followed by umbilical cord diameter (R² = 0.958), and abdominal diameter (R² = 0.949). The findings demonstrate that ultrasonographic foetometry is an effective tool for estimating the gestational age in Gaddi ewes.