There is often much debate round calving sucker replacement heifers at 24-months-of-age, and while it is seen as standard practice on most dairy farms, some suckler farmers are more weary of the practice.
According to the Irish Cattle Breeding Federation (ICBF) data, only 24% of beef heifers nationally calve for the first time between 23 and 26-months-of-age.
Contrary to this, the top 10% of commercial suckler enterprises and suckler research farms are successfully managing to calve 100% of heifers between 23 and 26-months-of-age.
Teagasc research has also shown that a heifer calving for the first time at 36-months-of-age consumes 65% more grass, 96% more silage and 33% more concentrates than an equivalent heifer calving at 24 months of age.
Regardless of the system, the Teagasc advice is that suckler farmers should target to calve suckler-bred heifers at between 23 and 26-months-of-age to increase profitability and reduce the carbon footprint of the enterprise.
In the Teagasc Beef Newsletter for May, it was outlined that heifers need to be 60% of their mature body weight at breeding.
A suckler-bred heifer with a mature weight of 700kg should be at least 420kg at breeding and heifers that are bred lighter than this are more prone to having issues calving and going back in calf the following year, as well as reaching their mature body weight.
With good grassland management and compensatory growth, suckler replacement heifers should meet target weights.
The advisory body suggests that replacement heifers could be bred in June to an easy calving sire rated below 7% for calving difficulty with a reliability figure above 80%.
A sire that meets these two specifications and has a short gestation should result in replacement heifers calving on schedule early next year.