Table 1. Description of the features used for building estrus detection models.

Feature
Current smoothened residual-tail surface temperature (rST) *
Minimum value during the last 12 h of smoothened rST (12 h min.)
Minimum value during the last 24 h of smoothened rST (24 h min.)
Minimum value during the last 48 h of smoothened rST (48 h min.)
Maximum value during the last 12 h of smoothened rST (12 h max.)
Maximum value during the last 24 h of smoothened rST (24 h max.)
Maximum value during the last 48 h of smoothened rST (48 h max.)
Difference between the current smoothened rST and 12 h min.
Difference between the current smoothened rST and 24 h min.
Difference between the current smoothened rST and 48 h min.
Difference between the current smoothened rST and 12 h max.
Difference between the current smoothened rST and 24 h max.
Difference between the current smoothened rST and 48 h max.

* Residual tail surface temperature (rST) was calculated as actual ST − mean ST for the same hour on the previous 3 days.