Estrus Detection Through Vaginal pH in Saanen Etawah Crossbreed Goats

In goats, weak estrus behavior is potentially caused by a decline in reproductive efficiency. In the present study, aim was to measure the vaginal pH to determine the accuracy of lust detection in Saanen Etawah crossbreed goats. Thirteen Saanen Etawah crossbred does (Capra hircus) with body condition score of 2-3 were used. The dose were fed concentrate, provided forage and water ad libitum. The experiment was conducted during the natural estrous cycle. Vaginal smears were collected from each dose every day over a 60 days period to determine the time of each phase of the estrous cycle. The vaginal pH was measured using pH indicator paper; simultaneously, the blood was sampled from the caudal vein into anticoagulant-coated tubes following estrous cycle, covering estrus (E/day-0), metestrus (M/day-3), diestrus (D/day-12) and proestrus (P/day-15). The concentration of plasma estrogen and cortisol was determined by solid phase competitive enzyme-linked immune sorbent assay and the correlation between vaginal pH with each phase of estrous cycle and estrogen level was found. The changes in vaginal pH were confirmed with estrogen and cortisol profile at each estrous phase. The highest vaginal pH and estrogen content were found during estrus, whereas, the lowest vaginal pH and estrogen content was found during diestrus. Furthermore, the cortisol level was significantly different in each phase of the estrous cycle; the highest level of cortisol was observed during proestrus. The correlation between vaginal pH and estrous phase indicates that the vaginal pH can be a useful parameter for estrus detection.