How do I manage and feed the ‘future of my herd’ over the winter?
Calving heifers at 24 months-of-age is no easy task and requires some precise management. However, it must be noted that farmers who calve heifers at 24 months operate more profitable enterprises.
Recent data published by the Irish Cattle Breeding Federation (ICBF) indicates that the percentage of heifers calved at 22-26 months has slipped by 2% to just 23% in 2018 (national average).
Farmers need to identify replacements and – according to Teagasc – weanling heifers from good cows that have achieved 1.1kg/day or better – since birth – should be selected; heifers should also be chosen on their genetic merit.
Weighing heifers on regular occasions is an essential component of the management process. At weaning, the heifers should have weighed 260kg. At housing (mid-November), heifers should be 300-320kg.
According to Teagasc, heifers need to achieve an average daily gain (ADG) of 0.6/kg/day over the housed period. By testing the quality of their silage, farmers can make adjustments in the level of concentrates being fed.
Farmers with good-quality silage (68-70% DMD), Teagasc says, should be feeding 2kg of concentrates in order to achieve an ADG of 0.6kg/day. Farmers feeding poorer-quality silage may need to increase concentrates by 1-2kg/day.
Care must be taken not to overfeed heifers, as this will lead to increased difficulties at a later stage. Farmers also should ensure that all heifers are free from disease and parasites. Correct ventilation and feed space are very important to ensure nothing inhibits the potential growth of the animal.
In spring, an early turnout is essential (weather permitting) to avail of compensatory growth. According to Teagasc, typical turnout weights should be 380-400kg for continental-type heifers.
Following a successful early turnout in spring, heifers should receive two vaccinations approximately eight weeks ahead of breeding – one for Bovine Viral Diarrhoea (BVD) and one for Leptospirosis.
In addition, four-to-six weeks on good-quality grass should leave heifers weighing in the region of 420kg at mating (60% of mature body weight).