@ARTICLE{Khodaei, author = {Khodaei, Mahdi and Ghasemi, Hosein Ali and Salehizadeh, Abolfazl and }, title = {Effect of Different Levels of a Blended Supplement Including Probiotics, Prebiotics and Enzymes on Productive Performance, Blood Metabolites, Hormonal Profile and Antioxidant Status of Laying Hens}, volume = {13}, number = {38}, abstract ={Extended Abstract Introduction and Objective: Because enzymes enhance the digestibility of feeds by increasing the availability of minerals and the digestibility of protein and amino acids, the utilization of enzymes is known as an effective method for increasing profitability in the poultry industry. In addition, certain enzymes are able to hydrolyze non-starch carbohydrates, resulting in an increase in feed energy utilization and the release of additional phosphorus through the degradation of phytic acid. The purpose of this study was to investigate the effects of a blended supplement consisting of probiotics, prebiotics, and enzymes (containing protease, phytase, lipase, and different carbohydrase) on productive performance, blood metabolites, hormone profile, and antioxidant status of laying hens. Materials and Methods: For an 8-week trial, 120 laying hens (52 weeks of age) were used in a completely randomized design with three treatments, eight replications, and five hens per replication. The experimental treatments included the control treatment (no additives) and treatments with complex enzyme supplements at 250 and 500 mg per kg of feed. Egg production, egg weight and feed intake were recorded daily. Egg quality traits and blood biochemical parameters were evaluated at the end of experiment. Results: The results showed that the treatment receiving 500 mg/kg of blended supplement had a greater egg production, greater egg mass, and while feed conversion ratio compared with the non-supplemented treatment (control treatment). The percentage of abnormal eggs was lower in all of the treatments that received the blended supplement compared to the control. A linear increase was observed in the blood levels of cholesterol, albumin, triiodothyronine, total antioxidant capacity, and superoxide dismutase activity after the inclusion of the supplement in the diet. In contrast, the concentrations of glucose, phosphorus, uric acid, alkaline phosphatase, TSH and T4 hormones, malondialdehyde, and nitric oxide, as well as the activity of blood glutathione peroxidase and catalase enzymes, were not affected by the experimental treatments (p>0.05). Conclusion: In conclusion, including the blended supplement in the diet of laying hens, particularly at the level of 500 mg/kg, during the second phase of the laying cycle has a positive effect on both production performance and health status, which may be attributed to an increase in antioxidant status and a decrease in stress levels. }, URL = {http://rap.sanru.ac.ir/article-1-1309-en.html}, eprint = {http://rap.sanru.ac.ir/article-1-1309-en.pdf}, journal = {Research on Animal Production}, doi = {10.52547/rap.13.38.128}, year = {2022} }