Genotypic and environmental differences in extract viscosity of barley and their relationship to its nutritive value for broiler chickens

Abstract

Sixteen barley cultivars selected for variation in extract viscosity were grown at five locations across western Canada. Differences in extract viscosity among locations were most apparent for high viscosity genotypes while those exhibiting low viscosity were more uniform across locations. Eight barley genotypes grown in a single location representing high and low viscosity traits were given to broiler chickens in a 3-week growth study. Chicks fed on low viscosity barley gained significantly faster ( P < 0.01), and converted feed more efficiently ( P < 0.01) than those given high viscosity barley. Two high and two low viscosity genotypes were given to chicks with or without β-glucanase ( Aspergillus niger) supplementation. With no enzyme addition chicks given low viscosity barley surpassed those given high viscosity barley with respect to growth ( P < 0.01) and feed conversion ( P < 0.01). Enzyme supplementation improved chick performance with both barley types, however the response was greater for high viscosity barley. Performance of chicks fed on enzyme-supplemented diets was similar for high and low viscosity barleys.