Application of prodigiosin pigment extracted from <i>Serratia marcescens</i> as a functional feed additive for improving quail performance and health

The experiment assessed the influence of using prodigiosin as a new feed additive on growth performance, carcase traits, digestibility of nutrients, digestive enzymes, blood metabolites and intestinal microbiota of growing quails. Two hundred and fifty one-week-old quails were randomly distributed into five groups with five replications for each one. The 1st group was fed on the basal diet (BD, 0 mL prodigiosin) only and was considered the control group. Whereas the 2nd, 3rd, 4th and 5th groups were fed on the BD containing 1, 2, 3 and 4 mL prodigiosin/kg diet, respectively. The main findings included significant improvement of the quail’s growth performance with the dietary presence of prodigiosin at levels more than 1 mL/kg diet. Significant increases in digestive enzyme activity as well as significant decreases in intestinal pH and caecal microbiota counts were achieved with prodigiosin. The prodigiosin dietary supplementation reduced plasma total cholesterol, triglycerides, low-density lipoprotein (LDL) and very low-density lipoprotein (VLDL) but a marked increase in high-intensity lipoprotein levels (HDL) concentration was reported. Prodigiosin also significantly increased the immunoglobulins, complement, lysozyme and antioxidant levels such as total antioxidant capacity (TAC), superoxide dismutase (SOD), catalase (CAT), glutathione (GSH), glutathione peroxidase (GPX), along with a marked reduction of malondialdehyde (MDA) level in quail plasma. The net revenue and economic efficiency of treated quails was significantly increased with prodigiosin supplementation; the best values were observed in prodigiosin 2 mL/kg diet. Therefore, based on the results obtained, prodigiosin can be effectively used as a nutritional supplement, and the optimal level was 2 mL/kg of diet.