Skip to main content

5 Oct 2020

Visual heat detection


A large number of studies show that cows’ heat behaviour has weakened over time. On one hand, you can try to improve/strengthen cows’ ability to show heat. On the other hand, you can try to improve the sensitivity of the way you do heat detection.

Finding the problem

The frequency of finding heat when detecting visually depends on the number of observations per day, the time of observation and the duration of each individual observation.
Low heat detection rate may be due to detecting heat at the wrong time, or in shorter periods of time. If you have more staff members detecting heat at different times, it is important to agree on which heat signals to look for and which signals should lead to insemination and that the information is handed on and collected.


The best times to detect heat in a herd depends on the work routines in the individual herd, but not at the same time as the cows are busy doing other things.

Heat signs can be categorized as:

  • No certain signs of heat
  • Reliable signs showing that the animal is in early heat. Service within 10-20 hours
  • Very reliable signs of heat. Service immediately

Focus areas

  • Include as many heat signs as possible when detecting heat
  • Perform heat detection minimum three times a day for at least 20 minutes a time (one should be in the night between 6 pm – 6 am.
  • Combine visual heat detection with activity measurements
  • Train your staff members doing heat detection thoroughly and enable them to pass on information to each other.

    Source: SEGES, Denmark