Fetal age determination in Murrah buffaloes from days 22 through 60 with ultrasonography

Abstract

Murrah heifers (n,20) that were inseminated at spontaneous or induced estrus and maintained mature corpus luteum up to day 22 post-insemination, were subjected to serial transrectal real-time ultrasound scanning of fetus, every alternate day from day 22 through 60 to correlate fetal measurements with gestational age. Mean length of the embryo increased from 3.07±0.04 mm on day 22 to 60.55±0.58 mm on day 60 post-insemination. The heart beat, amnion, optic area, limb buds, tail bud, optic lens, umbilical cord, split hooves, fetal movements and genital tubercle were first visualized on mean post-insemination day 27.1, 30.4, 32.4, 34.8, 36.7±0.21, 40.8, 40.9, 42.7, 45.0 and 49.8, respectively. Fetal growth curve best fitted with the Gompertz model. It was then used to ascertain gestational age of 74 pregnant buffaloes for validation and its accuracy, determined from farm AI records, was ±1 day in 67.6% buffaloes and ±2 days in 87.8% buffaloes. The information generated in the present study can be used to predict the gestational age of buffalo fetus more accurately.