A beef heifer’s natural ability to mature quickly, show heat and go in calf will undoubtedly influence how profitable she will be in an Irish suckler herd. This natural ability to be able to calve down at 24 months of age is influenced by genetics, among other things.

Of course, in most cases, these genes are brought into a commercial suckler herd via a pedigree stock bull. So it is important that beef pedigree females are showing a natural ability in this area. When we look through the performance of pedigree first-calvers across the main beef breeds, unsurprisingly there is nearly more variation within a breed than between them.

Tremendous improvements have been made in these traits across the breeds over the last number of years. Our pedigree breeds have always been to the fore in making constant improvements in terminal traits such as weight gain and carcase merit.

Calving at 24 months will increase the amount of calves the cow will have in their lifetime and, in turn, increase sales. \ Odhran Ducie

A trait such as “age of first calving” poses a different challenge, however, as it cannot be deduced from the looks of a bull how fertile his daughters will be and what their ability to calve down at 24 months will be like either. It is only through recording lots of mating, calving and ancestry data that this trait can be properly analysed and that trait leaders in terms of breeding cows and sires can be identified.

The same is true for calving interval. It is another “invisible” trait. The human eye cannot judge a bull for how quickly his daughters will be able to go back in calf. Again, great strides have also been made in this aspect of our national beef pedigree population. The replacement index, which has been at the core of the BDGP, rewards animals which perform well for these fertility traits, as well as having good beefing potential.

Bull lists are now unrecognisable compared with how they were 10 years ago. We are able to identify bulls whose daughters have excellent fertility traits. The tables show a random selection of some of the top-performing beef AI bulls for these traits.

Excellent performances for this trait can be found across the breeds looking at the data behind the figures – take the Charolais Carrickbrack96 Hutch as an example.

On average, his 301 daughters calved at 29 months of age whereas their herd mates calved down around 31 months of age.

It is important that farmers are working with a herd of suckler cows that have natural fertility and all that goes with it in their DNA.

Several studies have shown that heifers that calve at 24 months of age live longer and are more profitable over their lifetime.

The genetic trends for these fertility traits are going in the right direction, but it is important not to be complacent and think that the job is done.

Thankfully, today in Ireland, we have the tools in terms of the genetics and the indexes to make continual improvements in this area.