Abstract
This study employed a meta-analysis to systematically evaluate the effects of selenium supplementation on slaughter performance and tissue selenium concentrations in broilers. Relevant literature published between January 1, 2015, and November 1, 2025, was retrieved from Chinese National Knowledge Infrastructure (CNKI), China Science and Technology Journal Database (VIP), Wanfang, Web of Science, Science Direct, and PubMed. Following systematic screening of 946 reports, 15 studies met the predefined inclusion criteria, comprising a total of 6,759 broilers. The analyzed outcomes included slaughter performance indicators (eviscerated yield, carcass yield, breast muscle yield, leg muscle yield, and abdominal fat percentage), as well as selenium concentrations in breast muscle and liver tissues. Sensitivity and subgroup analyses were performed to explore sources of heterogeneity, and publication bias was assessed using funnel plots and Egger's test. The results showed that dietary selenium supplementation significantly increased the eviscerated yield (SMD = 0.35, 95% CI [0.02, 0.68]) and carcass yield (SMD = 0.30, 95% CI [0.01, 0.59]), but had no significant effect on breast muscle yield, leg muscle yield, nor abdominal fat percentage. Selenium supplementation also significantly increased selenium concentrations in both breast muscle (SMD = 6.24, 95% CI [4.96, 7.51]) and liver (SMD = 5.06, 95% CI [3.56, 6.57]). Funnel plots and Egger's test suggested the presence of publication bias for the tissue selenium concentration indicators, but not for the slaughter performance indicators. Sensitivity analysis confirmed that the results were robust. The dose-response analysis indicated a discrepancy in the selenium levels required to optimize slaughter performance and tissue selenium concentration, with respective ranges of 0.41-0.50 mg/kg and 0.39-0.75 mg/kg. Considering both production efficiency and nutritional fortification, the recommended dietary selenium supplementation level is 0.41-0.50 mg/kg. In conclusion, dietary selenium supplementation improves specific slaughter performance traits and increased tissue selenium concentrations in broilers, suggesting potential applications in poultry production and the development of selenium-enriched chicken products.