VALIDATION OF GESTATIONAL AGE BY DEVELOPING FORMULAE AND ASSESSING EMBRYONIC AND FETAL DEVELOPMENT BY ULTRASONIC FETOMETRY IN BANGLADESHI JAMUNAPARI CROSSBREED GOATS

Abstract

The study was designed to estimate the gestational age and detect the appropriate parameter at different stage of gestation by measuring six different gestational parameters (CRL, BPD, TD, GSD, GSL and PD) through ultrasonography, assessing the relationship with actual gestational age in Bangladeshi Jamunapari cross breed goats. The study was conducted at SAQTVH, CVASU, Chattogram from Feb’21 to Jan’23. The does were examined trans-abdominally in standing position using 2.5- 5MHz convex transducer by real time ultrasonography. Pregnancy was confirmed by amniotic fluid and fetal heartbeat in early stage and other fetal structures (skull, ribs, femur, placentomes, etc.) in mid and late stages of gestation. Parameters were measured for estimating gestational age while the actual gestational ages were collected from the history of delivery of doe. The values were analyzed statistically. The formulae were also generated from linear regression equation to calculate the gestational age in goats at different gestational stage. The estimated and actual GA were compared and differed significantly in all parameters except BPD and TD whereas PD showed non-significant variation (P˃0.05) indicates as a reliable parameter for gestational age determination up to the 2nd trimester of pregnancy in studied population. The EGA and AGA was compared at three different stages (early, mid and late) of gestation where found a non significant variation with a high coefficient of determination in case of GSD (R 2 = 0.92), GSL (R 2 = 0.91), and CRL (R 2 = 0.92) at early stage, PD (R 2 = 0.80) and BPD (R 2 = 0.89) at mid stage and TD (R 2 = 0.96) at late stage of gestation in estimating gestational age. The EGA ± 1-5 (days) measurements were also calculated to estimate the expected days from delivery and showed no significant variance (P˃0.05) with respect to all measured parameters in case of EGA+1-5 days but in case of subtracting 1-5 days, the analysis showed a significant variation with respect to all parameters except TD. From the present study, it could be concluded that the GSD, GSL and CRL is a highly reliable for the estimation of GA in 1st trimester where BPD, TD and PD are at 2nd trimester whereas during 3rd trimester TD is recommended. Expected days from delivery can also varied +1-5 days in case of the derived equation used for all six parameters but can vary ± 4 days in case of EDD based on TD measurements.