Journal of Veterinary and Applied Sciences

Abstract
The aim of this study was to determine gestational age by utilizing sonographic measurements of crown-rump length, head length and biparietal diameter of foetuses of West African Dwarf goats. Intra-partum measurement of foetuses of 15 West African Dwarf does at known gestational ages was undertaken using trans-abdominal ultrasonography. The relationship between gestational age and measured foetal parameters was plotted as linear regressions and expressed as straight-line equations. Regression equations were established where the gestational age was the dependent variable while each of the foetal parameters was considered as the independent variables. The measurements were taken every other day starting from Day 23 to Day 59 for crown-rump length and, from Day 35 to Day 103 for head length and biparietal diameter. The results of correlation coefficients between the measured parameters and gestational age were R2 = 0.980, 0.988 and 0.966 respectively for crown-rump length, head length and biparietal diameter. These results clearly demonstrated that foetal crown-rump length, head length and biparietal diameter were highly and positively correlated with gestational age (p < 0.01; R2 = 0.980, 0.988 and 0.966, respectively) with foetal head length showing the highest correlation with gestational age. The regression (gestational) equations for prediction of gestational age of West African Dwarf goats based on these parameters were: y (days) = 0.4273crown - rump length (mm) + 22.52, y (days) = 1.0221 head length (mm) + 22.21 and y (days) = 2.0746 biparietal diameter (mm) + 20.691. These regression equations may be used to predict the gestational age of West African Dwarf goats of unknown dates of breeding as well as monitor the growth rate of foetuses with known breeding dates.
Keywords: Sonographic biometry, Gestational age,West African Dwarf Goats

How to cite this article:
Anya KOO, Ekere SO, Obasi LO and Ogwu D (2022) Determination of gestational age of West African Dwarf goats using sonographic biometry. Journal of Veterinary and Applied Sciences, 12: 14 – 24.