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 Knowledge for the CommonWealth

Pedometry Is Here as a Method of Heat Detection

Dairy Pipeline: May 1998

by Ray L, Nebel
Extension Dairy Scientist, Reproduction
Virginia Tech

Approximately 75 years have passed since the first published recognition that female mammals display a predicable increase in physical activity when in estrus. It is now practical on the farm to determine which cows are in heat with pedometry. Cows in heat increase walking activity 3 to 5 times their normal number of steps. The research literature describes the effectiveness of pedometry-aided heat detection when compared with visual observation. Efficiency and accuracy of pedometer technology compared with that of visual observation is variable, primarily due to housing (comfort stalls, bedded pack, grazing, etc.) and weather or season of the year when the study was conducted. However, averaging results from studies reported in scientific journals, the efficiency of pedometer systems average 83% and the accuracy of declaring cows in estrus were 85%. Pedometer technology commercially available today has improved greatly since its earlier use in most of these studies. Analytical capability whereby the pedometer can compare activity that has occurred in the present time period to a pre-set baseline time period (previous 10 days) allows comparison of activity within individual cows and thus increases the specificity of the system. All pedometer systems available today are integrated with the milking equipment. If you are considering a new milking system or a milking system up-grade this is the time to invest in a pedometer system for heat detection.

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