that is a really good site but I didnt really understand how I go about getting the rest of these apart from corn into their daily feed
"The most important sources of carotenoids in poultry feed are maize (corn), maize gluten, alfalfa (lucerne) and grass meals; these sources contain the pigmenting carotenoids lutein and zeaxanthin, which, together with other oxygen-containing carotenoids, are known by the collective name of xanthophylls."
Any suggestions - would cooked carrots help? someone else has suggested turmeric or paprika?