by | Apr 8, 2023


The carbon footprint of agriculture in Ireland is under the microscope and whether you agree with it or not, we have fixed targets to achieve in the next seven years.

From a beef production point of view, age of slaughter is the area that is expected to lead to the greatest reduction in emissions. The logic is simple; the longer an animal is alive, the more it eats.

Producing beef at a younger age, significantly reduces not only the carbon footprint of the beef produced, but also the input costs. 

The importance of age of slaughter is further highlighted in the Irish Cattle Breeding Federation’s (ICBF’s) recent announcement that it will soon have its own sub-index, which will feed directly into the existing terminal and replacement indexes.

This represents the first major change in the index calculations in seven years and there is an expected terminal breeding value increase of approximately €1/day lower slaughter age.


Simmental cattle have always been renowned for their rapid growth rate. This fact is to the fore if you look at recent reports from Tullamore farm.

The 2022-born Simmental heifers on the farm have an average liveweight in February or 435kg – 50kg higher than any other breed. The top was a February-born Simmental heifer which weighed 485kg at just a year old.

The top weight of last year’s bulls was a February-born Simmental weighing 580kg at a year old, which translates to an average daily gain of 1.52kg/day since birth. All this growth rate was achieved before the bulls even started their intensive finishing stage.

The kill data for the 2021 bulls was presented at the Tullamore Farm open day earlier this year, where the Simmental bulls produced the same carcass weight as the other main continental breeds 10 days earlier and with a higher fat score.

This level of performance is in line with previous results from ICBF’s Tully test centre. In one trial, eight Simmental bulls were slaughtered at 13 months with an average carcass weight of 374kg and a feed efficiency 6.2kg.

The top performer had a carcass weight of 404kg at 13 months with a feed efficiency of 5.98kg.

One of the biggest challenges of slaughtering bulls this young, is to achieve an adequate fat score, however the Simmental bulls averaged 3- for fat.

Another example is that in seven year of Tully trials, the average age of slaughter for Simmental steers was between 50 and 80 days younger that the other main continental breeds.

Weight for age has always been the motto of the Simmental breed. Our years of dedication to maximising growth potential, particularly pre-weaning has given the breed a head-start in what is probably the single biggest challenge facing the future of our sector.


As a sector we have been set a target of reducing the age of slaughter to under 24 months, and top-performing Simmental bulls are taking a further 10 months off that.

It’s not just 10 months less emissions, it’s 10 months less feeding too.

In summary, the key message is having a breed type that can be slaughtered at a young age with the necessary fat cover, will result in much less input costs, deliver greater returns and help in the carbon challenge.

NOTE: Thank you to the AgriIand Team, and also the Irish Simmental Cattle Society for the use of this article