Fiber-degrading enzymes improved egg production, quality, and apparent retention of components in post-peak Lohmann Brown-Classic laying hens fed a high-fiber diet

Dose response of fiber-degrading enzymes (FDE) on egg production, quality, and apparent retention (AR) of components was investigated in 48-week-old Lohmann Brown-Classic hens housed in enriched cages (4 hens/cage). A corn-soybean meal basal diet was formulated with 19 % wheat middlings and fed without or with 50, 100, or 200 g FDE/ton. The FDE was a blend of endo-1,4-β-xylanase and endo-1,4-β-glucanase (Natugrain® TS), at 5,600 and 2,500 U/g, respectively. The mash diets contained titanium dioxide (0.25 %) as an indigestible marker and phytase at 2,000 FTU/kg and were allocated in a completely randomized design (n = 10). Birds had free access to feed and water for 16 weeks. Hen-day egg production (HDEP), feed intake (FI), egg weight (EW), egg mass (EM), feed conversion ratio (FCR, FI/EM), eggshell thickness (EST), breaking strength (EBS), Haugh unit (HU), albumen height (AH), and yolk color (YC) were reported at 4-week periods. Excreta samples for AR determination were collected at 4 and 12 weeks. The FDE increased HDEP non-linearly (P < 0.001) with the highest value at FDE50. There were interactions (P < 0.01) between diet and period on EW; overall EW declined linearly and quadratically in response to FDE (P < 0.001). The EM and FCR exhibited a quadratic response to FDE (P ≤ 0.025), with FDE50 and FDE100 yielding the best outcomes. There were interactions (P < 0.01) between diet and period on egg quality traits; however, the overall FDE response was linear and non-linear. The EST peaked at FDE50, whereas HU and AH peaked at FDE100, and YC at FDE200. The AR of NDF increased (P < 0.001) linearly in response to FDE, whereas the AR of gross energy increased (P < 0.001) linearly and quadratically in response to FDE. Overall, supplementation with 50 to 100 g FDE/ton improved egg production, egg quality, and nutrient retention in post-peak laying hens fed a high-fiber diet.