31 August 2001

Whole-crops top margins

Is fermented whole-crop

economical for beef rearing/

finishing? Do high beef value

sires really improve progeny

performance?

Hannah Velten reports on

recent Harper Adams

University College trials

HEAVY carcass weights and relatively cheap feed mean high gross margins can be achieved on a whole-crop wheat/cereal beef rearing and finishing system.

Although beef producers have shown interest in whole-crop as a low cost alternative to grass silage in rations, there has been no formal study of stock performance, says Simon Marsh, senior lecturer at Harper Adams University College, Shropshire.

Beginning in 2000, Mr Marsh set out to provide performance data and gross margins for producers from a study of 55 Limousin x Holstein bull and heifer calves on a 15- to 16-month whole-crop/cereal beef system.

Calves were reared on four litres a day of whole milk until five weeks old. "This kept rearing costs to a minimum, although increasing milk feeding rates and a later weaning age could have improved long-term performance," adds Mr Marsh. From weaning to six months, 14% crude protein beef nuts and straw were fed ad lib.

Ad-lib whole-crop was offered from six months to 14 months. It was supplemented with a 17% protein 50:50 beet pulp/distillers grains blend plus minerals, with bulls offered 3.5kg a head a day and heifers 2kg a head a day.

The 6ha (15 acres) winter wheat crop, of Eqinox and Soisson varieties, was grown as a conventional cereal crop. "It was harvested on July 20 with the grain at soft-hard cheddar stage, for maximum ear starch content, at a 10cm cutting height. A chop length of 0.5-1in helped compaction in the Ag-bag," he says.

An additive was applied at four litres/t of fresh crop. The fermented crop analysis was 41.7% dry matter, 8% crude protein and 30.7% starch.

"Initially cattle were to be finished on the whole-crop system with increased concentrate feeding pre-slaughter. But foot-and-mouth meant we could not market stock, so concentrate feeding was reduced to delay fat deposition.

"In May, stocks of whole-crop ran out, but marketing of fat cattle resumed so stock were finished on an ad-lib 13% crude protein barley/soya mix with straw."

Calves were slaughtered at an average age of 16 months old (see results).

"Our target gross margin was £10 a head a month. Not only did actual gross margins exceed those achieved by silage beef producers recorded by Signet, the college had never before achieved these target margins with intensive cereal-fed heifers.

"The system is particularly suited to heifers, as they can be taken to heavier carcass weights without depositing fat. Most heifer carcasses met the specification demanded by the abattoir for supermarket trade," he says.

"Bulls also achieved greater weights compared with cereal-fed animals, as daily liveweight gain is relatively low on the whole-crop system. Our study shows it pays to take cattle to higher weights, when using relatively cheap feed."

Whole-crop costs £60/t DM for an 11t DM/ha yield, including growing, harvesting and storage costs. With arable aid payments, costs could fall to £40/t DM, he says. "Other benefits over grass silage include one harvest operation and higher DM content, which makes for cleaner cattle."

On this evidence, some producers feeding grass silage could consider converting to whole-crop. "Cattle will perform better on high DM silage than whole-crop at comparable levels of concentrate feeding. But there is no guarantee high quality grass silage can be made consistently. Depending on production requirements and farm resources, try whole-crop," suggests Mr Marsh.

Whole-crop trial results

Heifers Bulls

Weight at slaughter 488 619

Daily lwt gain

(kg from birth) 0.92 1.18

Carcass wt (kg) 259.3 349.8

Carcass

classification O+/R4L R3

Gross margin

a head £160 £254

Stocking rate

(cattle/ha) 9.7 9.4

Gross margin/ha £1,552 £2,387