Electronic measurements of vaginal electric resistance (VER): Current status for estrus detection

1.Title: Electronic measurements of vaginal electric resistance (VER): Current status for estrus detection, timing insemination and pregnancy diagnosis in cattle and buffalo

Authors: GN Purohit, Satish Kumar and Devendra Kumar

Source: Ruminant Science (2019)-8(2):145-152.

How to cite this manuscript: Purohit GN, Kumar Satish and Kumar Devendra (2019). Electronic measurements of vaginal electric resistance (VER): Current status for estrus detection, timing insemination and pregnancy diagnosis in cattle and buffalo. Ruminant Science 8(2):145-152.



Electronic measurement of electrical resistance of vaginal mucous membranes (VER) emerged a couple of years back as a technique to detect the stage of oestrous cycle, pregnancy diagnosis and time insemination in dairy cattle and buffalo. Many studies in cattle and buffalo found a precipitous fall in VER at estrus, synchronous to decrease in plasma progesterone and increased circulating estradiol. On account of a close correlation of plasma LH with VER observed in many studies, insemination at low VER resulted in high conception rates. Although some workers did not find repeatable results with VER, a practical difficulty for the commercial use of VER in dairy herds is the requirement of daily recording which is time-consuming and has the potential dangers of creating inflammation in the vaginal mucous membranes. There is renewed interest in the design of new prototypes for VER and hopefully, they would substantially improve estrus detection and timing insemination in cattle and buffalo.



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