Effects of Lavender Flower Distillation Residue Powder on Performance, Egg Quality and Yolk Antioxidant Capacity in...

This study evaluated the effects of lavender flower distillation residue powder (LRP) as a dietary supplement on performance, egg quality and yolk oxidative status in laying Japanese quail. Seventy-five 24-week-old hens were allocated to three dietary treatments (0, 1 or 2 g/kg residue powder) for 10 weeks, with five replicate cages per treatment and five birds per cage. Feed intake increased at the inclusion level of 1 g/kg but decreased at 2 g/kg compared with the control group (p < 0.01), whereas egg production, egg weight, egg mass and feed conversion ratio were not affected (p > 0.05). Dietary supplementation reduced the proportion of damaged eggs (p < 0.05) and increased eggshell breaking strength (p < 0.01) in a dose-dependent manner. Yolk redness (a*) and Roche color score were higher in birds fed 1 g/kg of LRP (p < 0.01). Yolk radical-scavenging capacity (DPPH) increased at 1 g/kg (p < 0.01), while yolk malondialdehyde (MDA) concentration decreased with increasing inclusion level (p < 0.01). Overall, LRP may be used as a natural feed additive to improve eggshell integrity, yolk color and yolk antioxidant status in laying quail; however, the inclusion level should be carefully considered due to its contrasting effects on feed intake.