Dietary inclusion of micelle silymarin enhances egg production, quality, and lowers blood cholesterol in Hy-line brown laying hens

This study aimed to evaluate the effect of micelle silymarin (MS) supplementation on productive performance, egg quality, and blood biochemical parameters in laying hens. A total of 384 (Hy-Line brown, 28-week-old) laying hens were randomly distributed into one of four dietary treatment groups (eight replication per treatment; 12 hens per replicate) for a 12-week long feeding trial. Hens were fed a basal diet with the addition of 0%, 0.02%, 0.04%, and 0.06% of MS respectively. The results expressed that egg production percentage and egg weight were linearly (p < 0.05) enhanced at Weeks 0-6, 7-12, and 0-12, when 0%, 0.02%, 0.04%, and 0.06% of MS were added to laying hen diets. The feed conversion ratio and feed intake improved (p < 0.05) linearly at Weeks 0-6, 7-12, and 0-12 with increasing levels of MS supplementation in laying hens. The eggshell thickness and eggshell strength were linearly (p < 0.05) improved at weeks 4, 8, and 12 with an MS-supplemented diet. Additionally, eggshell colour, Haugh unit, and albumin height had no significant (p > 0.05) difference throughout the experimental period with different levels of MS-supplemented diet. The yolk colour of eggs showed significant (p < 0.05) differences at weeks 8 and 12 with levels of the MS-supplemented diet. However, at the end of the trial, the blood profile indicated that cholesterol levels decreased (p < 0.05) linearly, and triglyceride levels showed a tendency to decrease (p < 0.10) with MS supplementation. In conclusion, increasing the level of MS addition in the laying hen diet improved the egg production percentage and egg quality, reducing cholesterol levels in Hy-Line brown hens. However, this study indicates that MS can be added to the diet of laying hens up to 0.06% for improved egg production and egg quality.