The latest calving reports from the Irish Cattle Breeding Federation (ICBF) have been released and farmers can benchmark the fertility of their herd against both the average and top 10%.

This report looks at all dairy calvings in the herd between July 1, 2024 and June 30, 2025 and allows farmers to analyse their calving performance through a number of key performance indicators (KPIs).

KPIs such as calving interval; six week calving rate; heifers calving between 22-26 months; and average lactation of cows in the herd all contribute significantly to the profitability and sustainability on farms.

Evaluating your performance now will give you an opportunity to analyse how your calving season went and how the herd is performing from a fertility perspective.

Obtaining this information and benchmarking it towards the average and top 10% will give farmers a great idea of where they are and where they need to improve for breeding this winter for the autumn calving herds and breeding next April or May for spring calving herds.

The data from these reports should be discussed with your vet or your adviser to put an effective plan in place as it may require an alteration of the diet coming up to breeding, using more conventional straws, using a synchronisation programme for late calvers and heifers, and/or administrating a mineral bolus to cows.

The ICBF stated that "following the publication of the reports, the data indicates a positive trend in the fertility performance of the national herd."

The National Statistics are based on data from over 13,500 herds with 30 or more dairy cows.

The calving interval - which is the length of time between two successful calving - remained consistent in the last couple of years, as from 2021 to 2022 it remained stable at 388 days.

This decreased to 386 days in 2023, followed by a further reduction to 385 days in 2024 and 2025, resulting in an improvement of three days over the past five years, which shows a gradual improvement in herd fertility and reproductive efficiency.

The spring six week calving rate - which is the number of heifers/cows that calves during the first six weeks - was 67% in 2021, followed by a slight decline in 2022, but the rate then showed a steady upward trend to 69% this year.

The six-week calving rate is considered to be one of the most important KPIs in dairying as when dairy cows are calving earlier in the spring, it leads to a longer lactation, increased days at grass, and subsequently an increase in milk production.

The percentage of heifers calving between 22-26 months-of-age was 75% this year, declining from 76% in 2024.

This can be somewhat attributed to the severe weather last spring, as it was previously reported that there was a lot of underweight heifers ahead of mating 2024.

Ensuring that heifers are calving at the optimum age is crucial for increasing a heifer’s lifetime productivity, reducing the rearing costs, and improving overall herd efficiency.

The average lactation for cows in the herd has remained stable at 3.7 lactations from 2023 to 2025, after increasing from 3.5 in 2022.

This positive trend indicates that cows are remaining productive with lower empty rates and lasting longer, leading to increased lifetime productivity and profitability.

The percentage of replacements bred to dairy artificial insemination (AI) has steadily increased from 59% in 2021 to 62% in 2025.

This shows an increased enthusiasm among farmers to drive on genetic gain, as AI sires in general have a better genetic merit than the average stock bull.

As a result, the percentage of births with a known sire has also increased from 64% in 2021 to 71% in 2025.

Fertility traits in the national dairy herd 2025, according to the ICBF areas follows:

Overall, herd fertility on farms is improving, which can be largely attributed to the increased AI usage and genetic improvements on farms.

However, there is still many herds considerably behind fertility targets. These farms should see where their breeding and genetics need to improve, and focus on high genetic merit bulls and targeting traits to improve on specific cows.

Ahead of the breeding season, whether it is this December or in April or May next year, take time to pick out the best performing cows and match them with bulls that will improve traits they are lacking.

No one bull is going to suit your whole herd. For instance, use a milkier-type bull for cows with low litres but decent solids and a higher solids percentage bull on cows that are producing a lot of milk but have lower solids.

This targeted breeding strategy will improve farm productivity and profitability. Planning now will aid in getting cows prepared and ready for insemination within the first three weeks of breeding.