The Effect of Diets Containing Yellow Corn and Wheat in Different Ratio on Performance, Egg Shell Quality and Yellow Colour in Laying Hens

This study was carried out to determine the effects of 4 different diets of wheat/corn ratio, 100/0, 67/33, 33/67 and 0/100, on performance, egg quality and weekly egg yolk color in laying hens. In the study, which lasted for four weeks (28 days), a total of 60 laying hens at 60 weeks of age were allocated to 4 experimental groups with 5 replications, 3 hens in each pen. As a result of the study, while the body weight change was found to be significantly higher in the group fed with a diet containing wheat than corn source (P <0.05), while the effect of treatment diets on egg production, feed consumption, feed conversion coefficient, egg weight and mass was insignificant (P <0.05). Eggshell strength, shell weight and shell thickness were significantly lower in diets containing only corn-based diet (P <0.05). According to the Roche color scale, there was no difference between the groups in terms of egg yolk color at the beginning of the experiment, while the colour measurements on the 7th, 14th, 21st and 28th days, wheat/corn ratio of 33/67 and 0/100 of groups were significantly higher than the wheat/corn ratio of 67/33 and 100/0 of groups. The lowest colour value was in the group with a 100/0 wheat/corn ratio, that is, the group fed on a wheat-based diet (P <0.05). According to the L *, a * and b * values of the egg yolk colour, there was no significant difference between the groups at the beginning of the experiment. The a * and b * values, which are indicators of yellow and red color, were significantly lower in wheat-based diets on the 7th, 14th, 21st and 28th days of the experiment and an increase was observed in the diet due to the increase in the corn level (P <0.05). The results of this study showed that; when it evaluated in terms of body weight change, eggshell quality parameters and egg yolk colour wheat/corn ratio would be appropriate as 33/67 in the diet, in other words: the diet should contain 40% corn and approximately 20% wheat in laying hens.