A study on first appearance of external developmental horizons and their use in approximation of age in the goat fetuses.

A total of 103 goat fetuses from 34 days (CR 1.55 cm) to full term (CR 42.00 cm) were observed for first appearance of external developmental horizons. Various major external developmental horizons viz. thoracic and pelvic limb buds, differentiated digits, closed eyelids, differentiated nostrils, initiation of teat formation were observed at second month; horn buds and hair around eye at third month; sparse hair on head and body, and beared hair at fourth month; opened eyelids and hair covering the entire body at fifth month of goat fetuses. These first appearance of external developmental horizons were age dependent and they would be useful as quick guideline for approximation of age in the goat fetuses from fresh or preserved specimens.