Anti‐nutritive activity of wheat pentosans in broiler diets

Abstract

1. To assess their possible anti‐nutritive activity wheat pentosans were isolated from a milling by‐product and added at graded levels to a sorghum‐based broiler chicken diet.

2. A water‐insoluble pentosan preparation (WIP, 720 g arabinoxy‐lan/kg) caused a depression of apparent metabolisable energy (AME) of 1.63 MJ/kg DM at the highest level of inclusion (41.9 g/kg). Broilers maintained on this diet showed significant growth depression and a decrease in feed conversion efficiency.

3. A water‐soluble pentosan preparation (WSP, 520 g arabinoxy‐lan/kg) showed less anti‐nutritive activity.

4. In a second experiment the AME of rice (pearled), maize, sorghum, wheat, triticale, barley and rye was determined. The AME values obtained were highly correlated (r= — 0.98, P<0.001) with the summed levels of pentosans and β‐glucans found in the cereals.

5. It was concluded that the pentosans of wheat possess anti‐nutritive activity when present in broiler diets and that similar polysaccharides may influence the nutritive value of other cereals.

Notes

Present address: CSIRO Division of Human Nutrition, O'Halloran Hill, S.A. 5158, Australia.

To whom correspondence should be addressed.