Leverage of lysozyme dietary supplementation on gut health, hematological, antioxidant, and immune parameters in different plumage-colors Japanese quails

The current study was conducted on two different feather-colored Japanese quail varieties (brown and white) to examine the impact of lysozyme (LZ) dietary supplementation on growth performance, hematological profile, serum lysozyme, phagocytic and antioxidant activities, along with the gut status and the relative expression of some antioxidant- and immune-related genes. Two forms of LZ; extracted from egg white (natural LZ (NLZ)), and the commercial LZ (CLZ) were included in this experiment. For each quail variety, 240 birds were randomly allocated into four groups with four replicates per group. The first group (control) ate the basal diet (BD) only. The other groups ate the BD supplemented with commercial lysozyme (CLZ, at 100 mg/kg diet), NLZ at 100 (NLZ1) and 200 (NLZ2) mg/kg diet. Different LZ treatments differentially modulated the quail's growth performance with significant increases in the final body weight of white-feathered quails fed the NLZ1 compared to other treatments. The NLZ2 and CLZ noticeably increased the total antioxidant activity (TA) in the white- and brown-feathered quails, respectively. Also, all LZ groups displayed distinct increases in the serum lysozyme and phagocytic activities. For gut status, both varieties exhibited increases in intestinal villi length and goblet cell count with significant reductions in the total lactobacillus, total coliform, and total bacterial counts. These effects were linked with marked modulations of SOD, CAT, GPX, andIL-1βgene expression levels in both quail varieties. Therefore, the LZ could differentially impact quail growth, immune and antioxidant status as well as gut health.