28 August 2012

3 minute read

Replacing barley in beef finisher rations with crimped maize will result in increased daily liveweight gain and carcase gains with an improved feed conversion ratio. “And the overall performance of the bulls in our study was very good, both achieving and exceeding recognised targets for intensive cereal beef production,” Harper Adams University College’s Simon Marsh told delegates at the British Society of Animal Science annual conference.

He explained that there was growing interest in feeding grain maize to cattle due to its high energy and starch content. “A relatively high proportion (350 g/kg) of the starch is rumen undegradable compared to 150 g/kg for rolled barley, which should help minimise problems with rumen acidosis,” he said. “Because of the lack of information on feeding grain maize to beef cattle in the UK, our objective was to evaluate the effect of feeding either crimped maize grain or barley to intensively finished dairy-bred bulls,” he said.

A total of 26 Holstein and 10 beef cross Holstein bulls, weighing 359 kg at 8.5 months of age and previously reared on an ad lib 140 g/kg CP cereal based ration, were allocated in a randomised block design according to breed and live weight. They were fed the following diets ad lib through to slaughter: barley mix, containing 845 kg/t of rolled barley, 40 kg/t of soyabean meal, 40 kg/t of rapeseed meal, 50 kg/t of molasses, and 25 kg/t of minerals; and maize grain mix, containing 860 kg/t of crimped maize grain, 60 kg/t of soyabean meal, 60 kg/t of rapeseed meal, and 20 kg/t of minerals.

Both mixes were analysed to contain 841 and 660 g DM/kg and 142 and 141 g CP/kgDM respectively. The maize grain, grown under plastic mulch, had a DM content of 620 g/kg and was crimped and ensiled with 3 l/t inoculant mixed at double strength.

The cattle were selected for slaughter at EUROP fat class 3. “The bulls fed crimped maize grain recorded higher carcase weights (+8kg), were slaughtered 13 days earlier and recorded improved FCRs and lower liver damage scores,” said Mr Marsh.

Liver abscesses are associated with mild acidosis from feeding high starch based diets. “So it could be assumed that the reduced incidence of liver abscesses observed was due the higher proportion of by-pass starch in crimped maize,” he added.

“The improved performance with the crimped maize grain fed bulls is likely to be due to improved efficiency of energy utilisation together with a reduced incidence of rumen acidosis. The bulls finished on the maize grain treatment recorded a reduced feed cost per kilogramme gain of 10 p/kg based on the costs prevailing at the time of the study.”

Full details: Marsh SP, Bletcher TH and Vickers M: “An evaluation of crimped maize grain for finishing beef cattle.”

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