Efficacy of Vaginal Electrical Resistance Measurement in West African Dwarf Goats Synchronized using Ovsynch and Double PG Protocol

Abstract

One of the major constraints to good reproductive performance in West African dwarf (WAD) goats is low estrus detection, this study investigates the use of vaginal electrical resistance (VER) as estrus detection in WAD goats. Thirty-six (36) WAD does were randomly divided into two synchronization protocols and a control; Group 1 was the control without hormonal treatment, Group 2, was administered with double prostaglandin, and Group 3 Ovsynch protocols. The results revealed that does in the control group (G1) showed an unpredictable pattern in the onset of estrus. The mean VER values of treatment groups are within the normal range. The onset of estrus correlated with the lowest VER reading post-treatment, observed 24 to 36 hours in 40% of does in both groups. Blood progesterone and estradiol revealed distinct but synchronized patterns in both groups. Group 2 displayed a consistent decline in blood progesterone from day 0 to 7, and a spike on days 7–11, attributed to the second prostaglandin analogue administration. The subsequent decline on days 12–13 signalled impending estrus, accompanied by a rise in blood estradiol. Group 3 exhibited a progesterone spike on day 10, with a corresponding decrease in estradiol. The study demonstrates that regardless of synchronization protocol, the lowest mean VER reading post-treatment corresponds to high blood estradiol and low progesterone concentrations. This consistent pattern highlights the reliability of VER measurements in predicting estrus, while no significant difference in VER means the two protocols offer flexibility to goat farmers in choosing synchronization methods based on specific breeding objectives.