The 2021 dairy calving reports were generated last week and this year’s report includes updates to the definitions of some important metrics. This follows a review of previous years stats where some herds figures were not giving an accurate representation of the calving performance of the herd. This year’s changes have also been incorporated into previous years national statistics.

Eligible cows

This is now defined as:

  • All cows that calved, in your herd, in the period from 01/07/2020 – 30/06/2021. Cows that calved twice in the period (e.g. July 2020 and June 2021) are counted twice.
  • All cows that calved, at any time, before 01/07/2020, did not calve in the report period and are still in your herd on 01/07/2021.

Previously, eligible cows was simply defined as “Number of dairy cows in the herd on 30th June”. This was not, however, giving an accurate picture of the calving performance of some herds. Take, for example, a herd selling a large number of calved heifers every year. The herd could calve down 200 dairy females but only have 150 in the herd on 30th June. The females calved in the herd and sold were not being included.

Females calved twice

In herds where calving takes place in mid-summer (June-July) it is possible to have cows that calve twice in the 12 month report period e.g. a cow calved in July 2020, went back in calf quickly and calved again in June 2021. In previous reports, such cows were only being counted once. This has been changed so that they are counted twice as there are two different calving events almost 12 months apart. Where a cow has twins she is only counted once as twins is multiple births from the same calving event.

These changes have no impact on the most important calving KPI’s for dairy herds namely:

  • calving interval
  • 6-week calving rate
  • heifers calved 22-26 months of age

You can access your herd’s dairy calving report online by logging into your HerdPlus account at If you have any queries on the dairy calving report please contact ICBF on 023-8820452 or email [email protected].