28 April 1995

A serious look at feed enzymes

ENZYME additives to wheat and barley-based broiler rations have now become commonplace, and their use in turkey feeds is being seriously explored.

"The whole area of enzymes in poultry feed has moved forward dramatically over the past four years," says consultant Chris Belyavin who runs feeding trials for commercial firms at De Montfort Universitys agricultural college in Lincs.

At present all his trial facilities are being used to conduct enzyme feeding trials – two with broilers and one with turkeys. The latest turkey trial with 40 pens each holding 25 BUT T8 hens is assessing the Finnfeeds enzyme Avizyme 1300 in wheat-based turkey diets.

Nutritional value

Mr Belyavin says enzyme additives are claimed to enhance the nutritional value of feed ingredients like wheat, to improve feed conversion rates in table poultry and to significantly raise the condition of litter in poultry houses.

"We have certainly been proving it here," says Mr Belyavin, who estimates that 90% of broiler feed now contains an enzyme of one sort or another. Initially it was thought that enzymes only played a significant role in starter feeds. "But recent trials have indicated a benefit from enzymes in finisher rations too. With turkeys it is less clear," he says. "The main benefits appear to accrue during the first six weeks of life in birds slaughtered at 14-weeks-old."

His views were echoed at a meeting of the UK branch of the World Poultry Science Association at Scarborough, Yorks, in March by Dr Mike Bedford of Finnfeeds International.

Dr Bedford said that although enzymes had been shown to have benificial effects, precisely how they functioned in the intestines of poultry was still debatable. His view was that they reduced the viscosity or "stickiness" of the gut contents of poultry, particularly where the ration contained high levels of wheat or barley.

Sticky litter

"Enzymes are probably used more for their effect on reducing sticky, wet litter than for any other reason alone," said Dr Bedford.

He reported that most broiler growers were now using enzymes in both starter and finisher feeds, that turkey producers were beginning to find enzymes beneficial, and that their use in pig feeds was becoming ever more popular.

"Twenty per cent of our Finnish made enzymes are now going into pig feeds," he said.

Among other firms promoting enzymes for poultry is Trouw Nutrition, which is introducing a new broad-spectrum poultry feed enzyme, Innozym AW, at next months Pig and Poultry Fair at the National Agricultural Centre on May 10 and 11. &#42

Chris Belyavin checks the litter condition of one of his feed enzyme trials.