24 May 2002

Cut costs and up digestibility

By Jonathan Long

IMPROVING wheat digestibility and lowering feed costs by up to 18p a cow a day can both be achieved using a simple technique to treat wheat, says south west consultant Pete Kelly.

Mixing feed grade wheat with 25kg/t of urea provides a feed with a protein content of between 17% and 20%, says Mr Kelly. "The technique was developed in Scotland by Mitch Lewis at SAC using liquid urea, we adapted it using urea prills and have worked with a number of farms over the past few years. All have reported excellent results using this method."

The urea reacts with enzymes in the wheat to produce ammonia gas, which works its way through the heap. This gas breaks down the seed coat to make the grains more digestible.

Treating wheat with urea will save time and cut costs says Mr Kelly. "With feed wheat costing about £55/t off the combine and fertiliser grade urea about £120/t the only other expense is the labour and power input when mixing," It can be produced for about £68/t, including labour.

On one 145-cow Glos unit, which Mr Kelly has been working with, they are saving about 18p a cow a day against the previous ration. "By using treated wheat we have been able to reduce dairy compound feeding by about 4kg a cow a day and extra protein in wheat has more than balanced out the drop in concentrate use."

Ensiling wheat is a simple procedure, he says. "Wheat should be harvested at between 30% and 35% moisture, it is better to start harvesting at 35%, particularly when cutting a larger area. When wheat is too dry at harvest extra water can be added afterwards, although this should be avoided when possible.

"Once cut, wheat must be mixed with urea as soon as possible. All the crop to be ensiled in one clamp should be mixed within 24 hours. The clamp should then be sealed and not opened for six weeks, but once opened it can be left open throughout the winter.

"Harvesting the crop at 35% moisture allows it to be cut in advance of main crop wheat. This means cultivations can start earlier, spreading the arable workload," he adds.

Mr Kelly has also been advising a 140-cow unit in Dorset which used the technique for the first time last year. "We grow about 400 acres of combinable crops, but have no drying facilities," says the farm manager. "Last year we were harvesting wheat at 19% moisture, with no drier and we needed to find another way of using the crop.

"Mr Kelly mentioned treating wheat with urea. We have previously used caustic treatment, but felt this a more suitable option.

"After harvesting, the crop was mixed through our mixer wagon with water and urea, this took about five minutes for each 6t load. It was then ensiled on a concrete pad with a top and bottom sheet. It is important to ensure the clamp is tightly sealed."

"While wetting the crop after harvest is not ideal, it will work and is suitable on farms which do not grow their own wheat," says Mr Kelly.

He suggests that both feed and fertiliser grade urea can be used, but first time users may find feed grade product more suitable, as it available in 25kg bags and so mixing is more accurate. "The Dorset unit used fertiliser grade urea with a cost saving over feed grade of about £1.50/t of wheat treated."

"While our only experience of mixing is with a wagon, we do not foresee any problems mixing wheat with urea on a concrete pad using a grain bucket. There is no need to mix the urea perfectly, as when it breaks down the ammonia gas produced will permeate through the heap."

In Dorset use of urea treated wheat has seen parlour feeding rates fall and now cows spend less time in the parlour and more time eating at the troughs.

"It also saved us time and money through the winter, when we were feeding caustic wheat we were mixing it weekly. This way we mix it all at harvest and the herdsman can go to the clamp when he needs it," says the farm manager.

The treated wheat mixes into the ration well and cows take to it straight away, he adds "We have found no problem mixing it into the ration through the wagon and cows do not seem put off by the strong ammonia smell."

But remember that wheat is not a balanced feed and producers must speak to a nutritionist before including it in rations, says Mr Kelly. &#42

Treating wheat with urea improves digestibility and cuts costs, says Pete Kelly.

&#8226 Easy to ensile.

&#8226 Feed cost savings.

&#8226 Adds value to wheat.