Two-year calving remains a real challenge for the Irish suckler industry, with just 22% of heifers currently calving between 22 and 26 months in 2020.
It’s a well proven fact that heifers that calve at two years of age are more profitable.
They have a higher output in their lifetime due to more calves produced.
It also allows farmers reduce stock groups and make quicker genetic progress.
Teagasc research at Grange has also shown that in a 50-cow herd with a 20% replacement rate, for every month that calving is delayed an additional cost of €490 is incurred (€50/heifer/month).
There is a thought that heifers will not be well enough grown out at 15 months to breed.
Some farmers argue that heifers will become stunted, will be difficult to calve and won’t go back in calf.
Taking a look at some of the ICBF data comparing the performance of 131,077 beef heifers that calved for the first time between 23 and 40 months, it would appear to dispel some of these myths.
Table 1 outlines the performance of the heifers calved at different ages.
Heifers calved at 23 to 26 months have a slightly better calving interval than heifers calved at an older age.
Heifers calving at two years of age required a little more assistance at calving and calf mortality was also marginally higher, but the benefits outweigh the negatives.
You could argue that the calving difficulty of the bulls used on the heifers calving at two years old is a little high.
The target should be to use bulls under 4% calving difficulty on heifers.
Table 2 outlines the target weights for heifers to calve at two years old.
To hit these target weights, heifers must gain 0.9kg to 1kg/day from birth to breeding.
Tullamore Farm heifer performance
The 2020 crop of Tullamore Farm heifers were weighed on 14 January 2021.
Heifers started creep feeding on 15 August 2020 and were fed 0.7kg/day between mid-August and mid-September.
They then moved on to 1.5kg of concentrates between mid-September until the end of December 2020, along with ad-lib baled silage.
This silage was baled off paddocks and ranged from 70 to 74DMD, 32% to 46% DM and 11% to 13% protein.
Concentrates were stopped on 1 January 2021 to avail of compensatory growth once turned out.
The plan was to turn out as early as possible in February, but this is looking like being closer to 20 February once the wet weather forecast at the weekend passes.
Heifers will be around 380kg at turnout. They will be grazing approximately 60 days before breeding starts and weight gains should hit 1kg/day or over it during this time, so that would mean heifers will be on average 420kg at breeding.
Heifers will receive the first course of the BVD and leptospirosis vaccine prior to turnout, with the booster shot planned to go in at the end of March.
Heifers will be tail-painted, with a planned breeding start date of 1 May 2021.
The average replacement index of the group is €147. The highest index heifer in the group is a Salers-cross at €201.
The national average of zero to one-year-old heifers in the last evaluation run was €96.
There are 47 weanling heifers currently on the farm. Ten of these will be kept for breeding, with a further 25 or 30 selected for our special in-calf heifer sale in October 2021.
The remaining heifers will be finished at the end of 2021 at 22 months.
Total lifetime consumption of meal to date is 204kg or €54/head.
Table 2 outlines the breed performance of the heifers. Table 3 outlines the breed performance of the 2020 born Tullamore Farm weanling heifers