Supplementation with <i>Aspergillus</i> fungi strain cultures on wheat bran on low-protein diets on performance, egg quality and blood characteristics of laying hens

1. In the contemporary economic-industrial world, ensuring the quality of poultry products through the use of healthy birds and providing nutritious diets has gained particular importance. The objective of this experiment was to evaluate the optimisation of laying hens' diets by reducing dietary protein by 4.61% and replacing it with 1.5 g/kg fermented wheat bran using two strains of <i>Aspergillus niger</i> and two strains of <i>Aspergillus oryzae</i>.2. This study was conducted on 240 laying hens at 41 weeks of age over 16 weeks, organised into four treatments and two control groups. One of the control groups included a diet with normal protein (CH) and another group with 4.61% less protein (CL). Both control groups received 1.5 g/kg raw wheat bran with their diet. In contrast, the four experimental treatments (N0, N4, O3, O4) received a diet with 4.61% less protein and 1.5 g/kg fermented wheat bran by their respective fungal strains, including two strains of <i>A. niger-</i>50101 (N0) and 92 844 (N4) and two strains of <i>A. oryzae</i>-5163 (O3) and 5164 (O4).3. The highest free radical scavenging activity, iron ion regenerative power and anticoagulant activity were observed in the control group containing uncultivated bran (<i>p</i><0.05). A significant reduction in phytate content and an increase in total phenolic compounds in the fermented bran extract N4 fungi were observed (<i>p</i><0.05). Additionally, this group showed the lowest level of egg yolk oxidation, as indicated by the induced malondialdehyde reaction.4. The N0 treatment had the highest feed intake and antioxidant activity in blood serum compared to the other groups (<i>p</i> < 0.05). The O4 group had the highest egg mass and egg weight, as well as the lowest levels of triglycerides and oxidation in the egg yolk compared to the other groups (<i>p</i> < 0.05).5. This study showed that fermenting wheat bran with <i>Aspergillus</i> spp. could enhance its antioxidant properties, which in turn improves egg quality.