Algorithm for Detecting Estrus in Hanwoo Cows

Abstract

The major limiting factor of the reproductive performance on many farms is the failure todetect estrus in a timely and accurate manner. The estrus detection for Hanwoo cows (Bostaurus coreanea) is generally performed by the visual observation which is estimated at about40% detection rate only. This recurring problem among farmers has motivated the developmentof various estrus detection aids. The mounting event duration threshold, standing heat eventfrequency threshold, estrus detection algorithm and so on, are necessarily needed in order todetect the estrus of Hanwoo cows accurately when using some automatic devices. However,they are not yet investigated for Hanwoo cows. Therefore, the objective of this study was toestablish a mounting event duration threshold and standing heat event frequency threshold morespecifically for Hanwoo breed by discriminating the duration of standing heat mounting fromshorter duration spurious mountings which routinely occur in cattle herds. One hundred and fiftyHanwoo cows with an age between 2 to 5 years were used in this study. Cows that wereexpected to come into estrus within 3days were randomly assigned to each compartment for theestrus group (EG). The heated cows were video recorded for about 24 hours until after postestrus. The results showed that Hanwoo cows can be considered on estrus when it standimmobile during mounted by any other cow in more than or equal to 3.15s and 3.22s inchest-tail head mount (CTM) and head-above back mount (HBM) and that occurs consecutivelyat least three times within 876.4s interval. The algorithm was also developed using thethresholds of the mount duration, mount interval and consecutive occurrence number.