Effects on egg quality traits of genotype and diets with mussel meal or wheat-distillers dried grains with solubles.

The aim of the study was to evaluate effects on exterior and interior egg quality and sensory characteristics of eggs from hens fed diets with admixtures of 3.5 or 7.0% of mussel meal or 20% wheat-distillers dried grains with solubles (DDGS). The mussel meal diets followed organic standards, whereas the DDGS diet was formulated for hens in conventional production. Standard diets, one organic and one conventional from a Swedish feed manufacturer, were included for comparison. The study used 164 Hy-Line White W-98 and 164 Hy-Line Brown layers housed in small-group furnished cages. Egg flavor or odor was not affected by genotype. Egg flavor intensity was stronger in eggs from hens fed either of the mussel diets or the standard organic diet compared with the conventional diet. There were no differences between any of the diets in egg odor intensity, off-flavor, or off-odor. The mussel diets and the standard organic diet gave stronger yolk pigmentation than the conventional and DDGS diet, respectively. Manure DM was lower with the admixture of 7.0% mussel meal than 3.5%. There was a tendency (P < 0.10) toward a difference between diets in dirty eggs, and the percentage was highest with 7.0% mussel meal. Diet or genotype had no effect on egg weight, albumen height, shell deformation, shell breaking strength, or proportion of cracked eggs. Genotype differences were found in weight percentage of albumen, yolk, and shell and in the presence of blood and meat spots and in percentage of dirty eggs. In conclusion, the majority of egg quality traits were unaffected by the diets studied. With the admixture of DDGS used in the present study, the characteristics of eggs were similar to those of eggs produced on the conventional standard diet. There was no indication of impaired egg odor or flavor with the used fractions of DDGS or mussel meal.