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1. The effects of various sources of natural carotenoids (Px alfalfa concentrate, tomato powder and marigold extract) as feed additives in quail diets on egg yolk pigmentation and carotenoid composition were investigated.

2. Adult Japanese quail were fed one of 5 different diets for 23 d: three diets each contained Px alfalfa concentrate (PX) or tomato powder (TP) or marigold extract (MG), one diet contained marigold extract and tomato powder (MG + TP) and a control diet (wheat/barley based) was low in carotenoid. All products were added at a rate of 2%, apart from marigold extract which was added at a rate of 0·2%.

3. Visual assessment of yolk colour (Roche colour fan) showed a stabilised yolk colour of 1·6, 7·7, 8·5, 8·8 and 10·6 for the control, PX, TP, MG and MG + TP treatments, respectively.

4. The total carotenoid concentration of the egg yolks were 2·2, 22·4, 4·1, 39·0 and 37·7 µg …