Effects of spinach and Labada leaf powders with or without NSP-degrading enzymes on performance, egg quality, and yolk pigmentation in late-phase laying hens.

The present study evaluated the effects of dietary supplementation with spinach (Spinacia oleracea) and Labada (Rumex patientia) leaf powders, with or without a non-starch polysaccharide (NSP)-degrading enzyme blend, on productive performance, egg quality, yolk pigmentation, and serum biochemical profile of late-phase laying hens. A total of 180 Lohmann Brown laying hens (86 weeks old) were randomly assigned to six dietary treatments in a 3 × 2 factorial arrangement: control, spinach (0.1%), or Labada (0.1%), each with or without enzyme supplementation, for 84 days. Dietary supplementation with spinach and Labada significantly (P < 0.05) improved feed conversion ratio, hen-day egg production, and egg mass compared with the control diet, while body weight and overall feed intake remained unaffected. Plant supplementation also increased eggshell surface area and markedly enhanced yolk pigmentation, as evidenced by higher Roche color scores and yolk yellowness (b*), with spinach producing the greatest pigmentation response. Enzyme supplementation improved feed conversion ratio during the later stage of the experiment and enhanced albumen height, Haugh unit, yolk yellowness, and sharp-end shell thickness. Most eggshell quality traits and serum biochemical indices, including calcium, phosphorus, glucose, total protein, cholesterol, ALT, and ALP, were unaffected by dietary treatments. However, enzyme supplementation significantly reduced serum aspartate aminotransferase activity, while a significant plant × enzyme interaction was observed for serum triglycerides. Overall, supplementation with spinach or Labada leaf powder effectively improved productive performance and yolk pigmentation without adversely affecting bird health, whereas enzyme supplementation primarily enhanced selected egg quality traits and reduced serum AST activity. These findings indicate that spinach and Labada represent promising natural alternatives to synthetic yolk pigments in diets for late-phase laying hens.