3 September 1999

Make the most of home-grown feed this winter

By Marianne Curtis

WHY look far afield for winter feeds when they could be within the farm gate?

At the Dairy Event, held on Sept 22 and 23 at Stoneleigh, Warks, the Dairy Research Consultancy and Milk Development Council will be demonstrating how to make the most of home-grown feeds.

Many grains including wheat, maize, rape, soya, peas and beans were crimped at DRCs headquarters at Reading University last year, says researcher David Beever. He believes that crimping offers a simple method of improving grain nutrient availability to stock.

"Caustic-treated wheat can be a hassle to produce. In the past, producers have been held back from using home-grown feed because they did not have the facilities to process it on farm. But grains do not need to be smashed to smithereens to maximise their nutrient contribution," he says.

Wheat is a flexible crop, says Prof Beever. "It can be harvested traditionally, whole cropped or harvested moist for crimping."

Another starch crop offering flexibility is maize, he believes. "Maize can be harvested at 35% dry matter for silage or as ground ear maize, using a snapper header which improves its energy contribution. Harvesting maize as grain gives a yield advantage and a higher oil content.

"When you are considering processing a high tonnage of feed it is probably worth investing in a crimper. But mobile crimpers are available for those seeking to process smaller quantities."

Crimpers start at £6000 for a farm machine processing about 6t/hour through to £30,000 for a contractors machine which processes about 35t/hour, says Roy Eastlake, technical manager at SAS Kelvin Cave. "Contractors charge about £10/t for crimping and adding an organic acid additive which prevents mould growth once the crop is ensiled," says Mr Eastlake.

But while additives are effective for starchy crops such as wheat and maize, they are less effective on protein crops such as peas and beans, says Prof Beever.

"Protein crops have a high buffering capacity which means that the pH of the ensiled crop can stay high, leading to deterioration." Extra acid may be a solution, but more research is required, he adds.

Whole rapeseed can also be crimped, providing a cheaper, high energy alternative to fat supplements. But caution over inclusion levels is needed to avoid intake concerns, says CEDAR researcher Chris Reynolds.

"Whole rapeseed contains about 40% oil on a dry matter basis but should not supply more than 30g/kg of total oil in the ration dry matter.

"For cows eating 20kg DM a day, up to 1.2kg DM of this can be crimped whole oilseed rape. Additional fat – above that already in the diet – can also be included for high yielding cows but total ration oil content should be less than 8% of dry matter, to avoid reducing intakes," he says.

Care is also needed to avoid whole rapeseed becoming rancid, says Prof Beever. "At CEDAR we ensiled whole oilseed rape, which is less than 6% dry matter, in dumpy bags with no additive. But I would advise feeding it within eight weeks to avoid rancidity."

Mixer wagons provide a good chance for sourcing alternative feeds, and Prof Beever believes there is little point in putting compound feeds into mixer wagons.

Producers should look at all options when considering what to feed this winter, including straights, by-products and home-grown feed, he advises. "On-farm processing is worth looking at. It provides a consistent, high quality and fully traceable feed."

But could feeding higher levels of home-grown grain lead to acidosis problems? Not so, says Edinburgh University vet, David Whitaker.

"Switching to more home-grown grain should not cause problems. The concentrate to forage ratio should not exceed 3:1 on a dry matter basis to avoid acidosis. These days, with multiple forages available, many units are feeding a ratio of 1:1 or less." &#42