Dietary alpha‑lipoic acid, sprouted wheat, and multi‑enzyme supplementation improve yolk fatty acid profile and antioxidant status in laying hens.

In a completely randomized trial, we investigated the individual and combined effects of sprouted wheat (SW, 5%), a multi‑enzyme blend (ME; 500 mg/kg), and alpha‑lipoic acid (ALA; 300 mg/kg) on yolk fatty acid composition and cholesterol content, blood biochemical indices, and oxidative‑stress‑related parameters in SuperNick laying hens, using 10 dietary treatments (n = 200; five replicates of four hens each) over a 60‑day period. Experimental diets containing 5% wheat or wheat sprout produced only modest changes in dietary fatty acid composition, with all diets remaining high in polyunsaturated fatty acids (PUFA) and low in trans‑fatty acids. Wheat slightly improved the PUFA to saturated fatty acid (SFA) ratio and the proportion of long‑chain n‑3 PUFA, while both wheat and sprouted wheat marginally reduced the excessively high n‑6 to n‑3 and linoleic / alpha‑linolenic acid ratios compared with the corn‑based control. In egg yolk, dietary treatments significantly modified saturated, monounsaturated, and polyunsaturated fatty acid profiles (P < 0.001). Alpha‑lipoic acid was the main driver of changes in SFA, lowering total SFA primarily through reductions in palmitic, myristic, and heptadecanoic acids, and increasing very‑long‑chain SFA. Yolk monounsaturated fatty acids were also affected, with ALA decreasing palmitoleic and oleic acids but increasing erucic acid, whereas wheat form and ME exerted smaller, more specific effects such as increased nervonic acid with sprouted wheat. Polyunsaturated fatty acids, particularly linoleic, alpha‑linolenic, eicosapentaenoic, and docosahexaenoic acids, were enhanced by ALA, especially in corn + ALA and wheat + ME + ALA diets, resulting in improved yolk n‑3 content and n‑3 to n‑6 ratio. Blood metabolites and antioxidant indices were strongly influenced by diet (P < 0.001), with ALA consistently lowering total cholesterol and triglycerides, modifying lipoprotein fractions, increasing superoxide dismutase activity, and reducing malondialdehyde, while sprouted wheat and ME alone showed limited but favorable effects on lipid peroxidation. Overall, ALA supplementation, especially in combination with wheat‑based diets and ME, beneficially modulated yolk fatty acid profile and systemic oxidative status, with only minor alterations in basal dietary lipid composition.