The performance of cross‐bred hens given free choice feeding of whole grains and a concentrate mixture and the influence of source of xanthophylls on yolk colour

Abstract

1. Cross‐bred hens were offered, from 25 to 73 weeks of age, diets based on either wheat or barley in the form of either a mash or as whole grains plus a concentrate mixture; four sources of xanthophylls were also compared. 2. Wheat reduced food intake by 8%, increased efficiency of food conversion and live‐weight gain while barley increased litter moisture content, and, during the first half of the laying year decreased egg production by 3.3% and yolk colour by 4%. 3. Hens offered whole grains ate 11% less food, converted food into eggs more efficiently, were heavier and laid larger eggs than those given the mash diets. 4. With whole grains yolk colour was less than with mash diets during the first 24 weeks of lay but this was reversed during the last 24 weeks of lay. 5. Either canthaxanthin or citranaxanthin or β‐apo‐8'‐carotenoic acid ethyl ester plus canthaxanthin in diets containing lucerne meal produced eggs with acceptable yolk colours.