The experiment was carried out to evaluate the effect of Azolla on the quality and cholesterol content of chicken eggs. A total of 240 eggs from different dietary groups of D₁ (control), D₂ (diet with 4% Azolla), D₃ (diet with 8% Azolla) and D₄ (commercial farming eggs) at different ages of the birds; A₁ (168 days), A₂ (196 days), A₃ (224 days), A₄ (252 days) and A₅ (308 days) having 12 eggs/ diet/ age group were collected from an ongoing project “ Using Azolla in the diet of laying hen”, Bangabandhu Sheikh Mujibur Rahman Agricultural University and commercial farms to measure egg quality traits. Accordingly, 32 and 8 eggs were collected to measure the dry matter and cholesterol content of eggs, respectively. The highest egg weight, albumen weight, yolk height and yolk width but the lowest eggshell weight and eggshell thickness were observed in D₄, followed by D₃, D₂ and D₁, respectively. Diet D₃ and D₂ showed higher albumen height, eggshell weight and eggshell thickness compared to D₁ and D₄. Of the two diets, D₃ performed better than D₂ in terms of albumen height, eggshell weight and eggshell thickness. The deepest egg yolk color was observed in D₃, followed by D₂, D₄ and D₁, respectively. Egg weight, albumen width, albumen height, yolk weight, yolk width, yolk height, eggshell thickness and yolk color were increased with the increase of the age of the birds (p<0.001), but decreased eggshell weight and egg yolk-albumen ratio with the increase of the age of the birds (p<0.01). Azolla increased dry matter (DM) but decreased moisture content of egg (p<0.01). The highest cholesterol was measured in D₄ and the lowest in D₃ and D₂, and intermediate in D₁. Hence, a lower level of cholesterol was observed in D₃ compared to D₂. Therefore, 8% Azolla increased the quality and dry matter and yolk color of the egg as well as reduced cholesterol content in egg yolk.

Keywords: Azolla, cholesterol, egg quality, laying hen, yolk color.