Heifers can meet needs if right system in place
Heifers can meet needs if right system in place
By Robert Davies
Wales correspondent
GIVEN the right system, heifer beef production can meet market requirements, even though heifers cannot match the growth rate of bulls or steers.
Finishing systems must, therefore, take account of the biological limitations that control growth and development, conclude consultants from ADAS, IGER, MLC and the University of Bristol who co-operated in DEFRAs Livestock Knowledge Transfer initiative.
Heifers have contributed about 5% of total GB beef kill over the past five years. "But improvements in both breeding and feeding systems are required to exploit the potential performance of heifers," says MLC beef scientist Duncan Pullar. "Using bulls of high beef value to sire calves will give heifers greater potential for growth and muscling."
The aim should be to achieve a growth rate of 0.8kg a day with optimum finished condition reached at 18 or 24 months of age. Carcass weight should be about 270kg with conformation and fat scores of R or better and 4L or leaner.
"Target weight is best reached using a non-intensive system. As the overriding aim must be to avoid getting heifers over fat, close visual monitoring and handling are important.
"When heifers are put on an intensive system very early they will probably have to be slaughtered at lighter weights and this can result in price penalties. Growth and slaughter weight targets depend on the type of heifer and system being used, but in all cases progress must be checked regularly."
The advice provided by Dr Pullar and the other Livestock KT experts, in their Heifer Finishing factsheet, reflects the variety of systems used in the UK. A typical one rearing spring born calves for slaughter at 18 months would involve rearing on dam or bucket, wintering inside on a ration formulated to give steady store growth until turn out at 12 months of age, then finishing on grass.
Alternatively, the yearling could be kept tightly at grass and finished indoors at 24 months old. Autumn born animals can be finished indoors at 18 months or stored over their second winter and sold off grass six months later.
On farms where there are facilities for intensive production, heifers could be killed at about 425kg liveweight when they are 12-13 months old. For the last six months of the finishing period they should gain 1.1kg a day, when given free access to a ration of 14% crude protein and 12.5-13MJ of energy/kg of dry matter.
"While high growth rates can be achieved, producers must bear in mind the risk of discounted payments for over fat carcasses. Optimum slaughter weight and carcass size will be limited, even with late maturing breeds," warns Dr Pullar.
Another alternative is to take a calf from heifers before slaughter. But poorer killing out percentage, conformation score and lean content can result and, while overall meat quality is not reduced, many in the meat trade resist handling once-bred heifers.
"There is plenty of experimental evidence that, when management is good, growth targets can be achieved and calving difficulties avoided," he adds.
The factsheet also looks at low input heifer finishing. This involves maximising use of grass/clover swards, through grazing and silage, to finish heifers at 19 months old, weighing 530kg liveweight.
Summer-born calves weaned at six weeks old can be reared on a beef concentrate and ad-lib silage to gain 0.7kg a day. Target weight at turnout on to pasture with a sward height of 6-8cm (2.4-3.2in) is 225kg. A growth rate of 0.9kg should be achieved at grass.
When they are housed, weighing about 400kg, they are fed ad-lib silage and gradually increasing levels of concentrate to gain 0.8kg a day to slaughter at 525-550kg.
lKT factsheets are available from the Institute of Grassland and Environmental Research (01970-823028, fax 01970-828357). *
When rearing heifers for beef, it is vital not to allow them to become over fat, says Duncan Pullar.
HEIFER BEEF
• Use top sires.
• Finish within 24 months.
• Penalty when over fat.
Tight management
Beef heifers require tighter management than steers, if excessive fat cover is to be avoided, according to Glamorgan milk producer Andrew Davies.
For many years replacements for the year round calving 300-cow dairy herd, his family run at Garn Farm, Cowbridge, were bought in, so there were plenty of heifers to finish on grass, silage and home-grown barley.
"Heifers must be heavy enough to return a reasonable price, which means they need to be killed at about 16 months of age," says Mr Davies.
His system is to grow heifers fairly slowly, inside or out, according to birth date, to develop a good frame before increasing the amount of barley-protein mix fed. As the new KT factsheet suggests, this can provide a 500kg plus heifer with acceptable 3 or 4L fat cover.