ANALYSIS OF ACTIVITY MEASUREMENT FOR ACCURATE ESTRUS DETECTION IN DAIRY-CATTLE

Errors in oestrus detection prevent many dairy farms from attaining their reproduction goals. A data base of animal activity sampled at 1-min intervals has been collected with electronic pedometers and correlated with other indications of oestrus. These data indicate that an activity-based decision of oestrus first occurs in close proximity to the pre-ovulatory surge of luteinizing hormone. The data base is also used to evaluate various comparison procedures for distinguishing between oestrus and dioestrus states. Three newly developed comparison procedures improve the accuracy of activity-based decisions for identifying oestrus and dioestrus periods when compared with commonly referenced procedures in the literature. The new methods (1) compare the current and past activity statistically as two independent treatments, (2) identify oestrus based upon both duration of an elevated activity and increased activity intensity, and (3) replace the averaging function with other digital signal processing techniques. Decisions based upon these procedures correctly identified approximately 70% of the periods of oestrus while accurately classifying 99% of the dioestrus periods. © 1994 Silsoe Research Institute.