[A prospective study of the usefulness of an intravaginal electric resistance meter for estrus detection in cattle].

The use of a device for measuring vaginal electrical resistance was tested in dairy cattle at the time of 496 inseminations as well as in five heifers and four gilts throughout the oestrous cycle. The device can be used in oestrus detection when there is a reliable and consistent difference in vaginal electric resistance, which can be estimated between the day(s) of oestrus and during the other days of the oestrus cycle. However, the results of tests using this device in cattle and gilts showed marked variations within animals during successive heats and cycles as well as between animals on corresponding days of the oestrus cycle. This experiment therefore showed that the device was not an effective aid in heat detection.