1 October 1999

Versatile whole-crop silage

By Marianne Curtis

WHOLE-CROP silage has something to offer everyone from modest yielding herds wanting to reduce forage costs, to high yielding herds requiring exceptional intakes.

That was the view of Biotal technical manager John Bax, running a forage clinic for producers attending the Dairy Event. "There is still the impression that whole-crops are low feed value which is incorrect.

"To maximise whole-crop nutrient values, however, the crop must be harvested at the correct stage. That is when the consistency of the grain is like Brie cheese; past the milky stage but not a hard grain. This gives a silage with high starch levels of about 37%."

Mr Bax explained how spring barley, undersown with grass could reduce forage costs for one Scottish producer with a herd averaging 6500 litres visiting the event. "Spring barley, harvested in late July would cost about £40/t DM, giving a yield of 8-9t DM/ha in one cut.

"Grass silage costs £70/t DM and it would take three cuts to achieve the same yield as for whole-crop spring barley. Also, the undersown ley can be grazed within two to three weeks of harvest."

Raising feed intakes to maximise yields profitably was the key objective for Mark Yearsley who will shortly become manager of the 300-cow herd at Lanhydrock Farms, Bodmin, Cornwall. "Cows average 8000 litres, but over the next five years we want to expand the herd to 500 cows averaging 12,000 litres."

Cows at the unit are housed for 10 months a year and fed a total mixed ration based on a 70:30 ratio of maize and grass silage. Biotal nutritionist Finlay Ross said feeding a mixture of forages was vital to maximise dry matter intakes safely.

"A cow giving 12,000 litres is producing 60 litres a day in peak lactation. To do this she needs to consume 28-30kg DM a day.

"Feeding whole-crops means intakes can be raised to these levels without risking acidosis because whole-crop starch is more slowly available than rolled cereal starch."

Mr Ross recommended a forage mixture containing equal proportions of grass, maize, whole-crop pea and whole-crop cereal. Offering a range of slow, medium and quickly available starch – using this forage mixture supplemented with crimped and rolled cereals – was vital to maximise feed use. &#42

WHOLE-CROPPING

&#8226 Harvesting stage critical.

&#8226 Cheaper than grass silage.

&#8226 Assists high intakes.