In the end, we can speculate whether these automated
devices are useful for reducing the constraints to heat
detection without decreasing reproductive performance.
Our results suggest a qualified “yes” with the proviso that
their use should be well considered. First, because of the
high risk of silent ovulation, performance before 50 DIM is
unreliable, but this is not a serious problem because the
recommended time for insemination is 50 days. However,
the devices we tested recorded only a part of sexual behaviors
[10], so combination of these devices with visual
observations, as reported by some authors, might be a
better strategy to increase estrus detection, conception
rates, and reduce culling due to perceived failure to
conceive [18,31]. Second, interpretation of the alerts should
be taken into account production data, such as peak milk
production, as well as the activity history of the cow, when
making a decision to inseminate. Thus, estrus detected by
an alert should be accepted as true only if it follows a
previous detection (visual or automated) by 18 to 24 days
or 36 to 48 days, suggesting an interval of 1 or 2 estrous
cycles [42]. Moreover, the purchase of such devices will
depend on profitability and must be considered in relation
to the farming system and the specific objectives of the
breeder. Indeed, the benefit could differ with the breeding
system management, including the season of calving, the
number of cows in the herd, and whether sexed or