This study aims at investigating the effects of different grain sources during pre-hatch (from diet of the breeders) and post-hatch (from the diet of broilers) on coloration (Roche color fan scores; L*, lightness; a*, redness; and b*, yellowness) as well as the growth performance in yellow-skinned chickens at market age (42 days old). In this experiment, six thousand yellow-skinned broiler breeders at 27 weeks were fed with a corn or sorghum and barley-based diet in which contained high (+) or low (-) xanthophyll levels, respectively. After the beginning of the trial, from day 41 to 42, eggs from two treatments were collected to artificial incubation. In this trial, 2×2 factorial designs were used and male chicks hatched from breeders fed with a corn or sorghum-based diet. According to the results, it demonstrated that hens fed with a corn-base diet were observed an elevated coloration both in the eggs and newly-hatched chicks (p<0.05). The dietary pigments improved pigment deposition in the egg yolk and the tissue of newly-hatched chicks. Besides, there was no difference in growth performance attributed to dietary grain sources both from hens or chicks. There showed no difference of coloration in abdominal fat, shank or breast skin (or kept at 4°C for 24 hours and 7 days) between two breeder grain sources (p>0.05). However, abdominal fat, shank and breast skin from the broiler chicks fed with the corn-based diet had a significantly higher RFC scores, a* and b* value than that fed with the sorghum and barley-based diet. The current results indicated that the broiler dietary grain sources (different xanthophyll contents), other than the breeder dietary grain sources influenced the pigmentation in abdominal fat, shank and breast skin, and the skins stored at 4°C in broiler. Therefore, it can be suggested that a low xanthophyll-containing diet (sorghum and barley-based diet) might be applied in yellow-skinned broiler breeders without causing negative effects of coloration or growth performance on their offspring at market age.
Keywords: broiler breeder; chicken; coloration; grain sources; growth performance.
2017, Japan Poultry Science Association.