Intensively finishing bulls on a ration rich in maize silage could increase margins and reduce feed costs, a study has revealed.
Research by Harper Adams University College, Shropshire examining the effect of concentrate feed level on the performance of maize-silage fed bulls, showed those fed a 75% maize silage ration achieved a gross margin a head of £393 compared to £338 for bulls fed 50% maize silage.
With feed accounting for 75-80% of variable costs in beef production and fluctuations in cereal prices during 2008 reducing profit margins from intensive finishing, the decision was made to look at other options, says senior lecturer, Simon Marsh.
“In February 2008 we faced the dilemma of making a loss when barley reached £157/t and O-grade Holstein bull calves were making £1.77/kg deadweight, so we took the decision to finish some bulls on maize silage.”
The 36 dairy-bred bulls weighing 225kg at six months old were fed a TMR of either 75:25 or 50:50 maize silage:concentrates (rolled barley, rapeseed meal and minerals) on a dry-matter basis.
“We decided to rear bulls to six months on a cereal-based diet because from three to six months we will typically record a DLWG of 1.6kg a day and it’s also important for rumen capacity to develop before feeding a forage based diet,” he says.
And results from the study were impressive, explains Mr Marsh.
“Bulls finished on maize silage reached slaughter weights of 585kg at 15.2 months old which is heavier, but later compared to bulls typically finished at Harper Adams on ad-lib cereals, finishing at 13.5 months old weighing 540kgs,” says Mr Marsh.
However, quality of maize at Harpers Adams was vital to the success of the study, with maize crops yielding up to 12t/ha DM with a high starch content of 30.5%, 33.9% DM and energy at 11.2ME.
“Starch in particular is important for a high level of performance, but getting such good quality isn’t possible on every farm in the UK. Where maize can’t be grown, another option that should yield similar results could be whole crop wheat.”
But, despite cereal prices easing back recently, Mr Marsh would still recommend maize silage as an alternative. “If the resources are in place such as the availability of clamps and feeder wagons, then increased margins can be made.”
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