Reliability of estrous detection in Holstein heifers using a radiotelemetric pedometer located on the neck or legs under different rearing conditions.

摘要: To evaluate the efficiency and accuracy of estrous detection using a new pedometry system that can measure hourly activity cattle, pedometers were attached to neck hind legs 15 Holstein heifers. Heifers reared in pasture for grazing, an open paddock, or tie-stall barn (an additional pedometer was front leg each these heifers). The most recent 24 h-total number steps compared 1 h-interval with mean value preceding days during reference period (RP). detected all 10 instances (100%) grazing heifers at 1.3 times thresholds 5-day RP but only 32% accuracy. pedometer, however, obtained 100% 83% 1.4 threshold 7-day RP. efficiencies accuracies detecting 12 under paddock condition 92 65% (neck, 1.3-fold, RP) (hind leg, 1.6- 1.7-fold, RP), respectively. Under tie stall condition, 92% 23 34% (1.2-fold, 3-day 78 78% 1.4-fold, 4- 6-day 87 (front Prediction ovulation time more precisely than those conditions. Our preliminary results indicate this has practical different rearing conditions, which affect criteria required detection. Furthermore, they also reliably detect estrus may be capable