Most English beef producers have much to gain from finishing continental-cross heifers at a younger age, while many need to focus their attention as much on avoiding under-weight as over-fat carcases, insists the English Beef and Lamb Executive (EBLEX), following a national study of beef production practice.
The study, involving detailed analysis of more than 150,000 passport and carcase records from animals slaughtered in English plants in 2004, reveals almost 75% of continental-cross heifers being slaughtered at over 22 months of age. And this despite little or no increase in average carcase weight after this age to pay for additional feeding, labour and housing costs.
At the same time, nearly 20% of continental-cross heifers were slaughtered at less than the 270 kg minimum carcase weight required by much of the modern meat market.
With price penalties of up to 20p/kg for under-weight carcases, producers clearly have much to gain from finishing heifers carefully to ensure they meet minimum weights. They need to take particular care in trying to increase carcase weights, however, since it is all too easy to increase the percentage of carcases in fat class 4H, considered over-fat by most processors.
The fact that up to 22% of continental-cross heifer carcases in the EBLEX study were recorded as fatter than the preferred 3-4L grades underlines this danger.
In many cases, the cause of both delayed marketing and lightweight carcases appears to be a failure to grow heifers fast enough to reach finished condition at an early enough age, if at all. Such slower growth rates have also been found to result in less well-conformed carcases at any given carcase weight..
Within the study, top third producers grew their heifers 0.17 kg/day faster than bottom third producers and slaughtered them five months earlier with improved conformation and no reduction in carcase weight.
On the evidence available, EBLEX advises English producers to manage continental-cross heifers to gain at least 0.7 kg/day over their lives, marketing them in fat class 3 or 4L at carcase weights of 270 kg or more at 18-24 months of age.
To achieve this target, producers should: a
- Base production on realistic budgets drawn-up in advance;
- Choose stock from sires with high EBVs for growth and conformationcarcase yield;
- Monitor growth rates against pre-set targets by regular weighing;
- Supplement grass with concentrates from mid-summer if necessary;
- House stock on full winter rations as soon as grazing conditions deteriorate; and
- Handle animals to assess fat levels at least every 2 weeks near the end of finishing.