Estimation of gestational age by ultrasonographic measurement of different fetal parameters in goats

Abstract

The study was designed to estimate the gestational age in goat by measuring different fetal parameters (CRL, BPD, FL) and PD by ultrasonography. The study was also aimed to compare the estimated gestational age with actual gestational age and design reference charts to calculate the gestational age in Bangladeshi goats for future use. The experiment was conducted at SAQ Teaching Veterinary Hospital, CVASU, Khulshi, Chattogram. All the registered outdoor female patient (does) which brought for pregnancy diagnosis in SAQ Teaching Veterinary Hospital CVASU were considered for the study. The does were examined transabdominally in standing position using 3-5MHz convex transducer by real time ultrasonography. Measurement of fetal parameters and placentomes were from ultrasongraphic images by electronic caliper by freezing the desired image on screen. Pregnancy detection was confirmed by amniotic fluid and fetal heartbeat in early stage and other fetal structures (skull, ribs, femur, placentomes, etc) in later stages of pregnancy. Fetal CRL, BPD, FL and PD were measured and gestational age of does were estimated. The fetal CRL, BPD, FL and PD were 58 ± 8.67, 28.17 ± 8.02, 47.88 ± 9.50 and 29.47 ± 2.46 mm, respectively. The estimated gestational age were 54.91 ± 7.33, 78.82 ± 17.11, 97.23 ± 11.95 and 96.94 ± 8.98 days, respectively. However, the recorded actual gestational age were 58.08 ± 8.57, 76.62 ± 16.31, 99.47 ± 13.39 and 93.38 ± 13.72 days, respectively. The estimated and actual GA in goats were significantly differed (P˂0.05) with respect to CRL, BPD and FL. However, in case of PD estimated and actual GA were not statistically different. The formula generated from linear regression equation from actual age of Jamunapari cross to estimate the gestational age in Bangladeshi goats as GA=1.27+0.98CRL, GA= 22.99+1.94BPD, GA= 34.67+1.35FL and GA= 4.43PD-37.41 with Coefficient of determination (R2 = 98, 96, 91 and 63) respectively. Transabdominal ultrasonography is a practical and reliable method for pregnancy detection in goat. From the present study it could be concluded that the CRL, BPD were highly reliable for the estimation of GA in 1st and 2nd trimester whereas during 3rd trimester FL is recommended.