ENGLISH BULL beef producers should look increasingly towards simple 100% maize silage-based rearing and finishing diets to maximise their profitability post-headage payments, advises the English Beef and Lamb Executive (EBLEX) in the light of the latest trial evidence.

DEFRA-funded trials just completed with Simmental x Holstein bulls at the University of Reading show rations based on maize silage alone giving clear performance advantages over those based on a maize/grass silage combination.

At the same time, they highlight the superior value of a basal maize silage diet over a combination of maize silage and cracked wheat in finishing rations.

Liveweight gains of 1.52 kg/day and feed conversion efficiencies of 3.87 kg feed/kg  gain were recorded during the rearing phase with a basal maize silage diet.

This compared to 1.45 kg/day and 4.12 kg feed/kg gain with a 2:1 mixture of maize and grass silage in the dry matter.

In the finishing phase, feed intakes were raised by the inclusion of cracked wheat in the diet.

Liveweight gains remained similar at around 1.50 kg/day, however, so feed conversion efficiencies were reduced – from 5.8 kg feed/kg gain to 6.15 kg feed/kg gain.

Overall, the best performance was achieved from both rearing and finishing rations based on 100% maize silage. 

This regime allowed the bulls to be taken from 120 kg to 620 kg in 326 days – 19 days fewer than with a maize/grass silage rearing ration followed by maize silage-based finishing – with no discernible difference in either carcase lean or fat content.

It also gave a lifetime feed cost of under 43p/kg liveweight gain (£208/head).

This represented a saving of more than 5p/kg or £25/head over the 48p/kg (£234/head) cost of the most expensive regime, suggesting substantial improvements in bull beef profitability through the wider use of simple maize silage-based rations.

The new EBLEX Quality Standard for beef, to be launched on 24 September 2004, specifies that bulls must be no older than 20 months at slaughter and if they come from the dairy herd the maximum age is reduced to 16 months.

Lifetime Bull Feeding Costs on Different Rearing : Finishing Diets (CEDAR trials)