Meta-analysis of dietary chicory (Cichorium intybus L.) modulation of the growth performance of broiler chickens.

Antibiotic growth promoters are increasingly restricted in broiler production over concerns about antimicrobial resistance, prompting interest in phytotherapies such as chicory. However, individual trials on dietary chicory in broilers report inconsistent effects on growth performance, limiting confident commercial translation. This study synthesized data from 2010 to 2025 to estimate the pooled effect of chicory on feed intake (FI), body weight gain (BWG), and feed conversion ratio (FCR) in broiler chickens. A random-effects model computed standardized mean differences (SMD) with 95% confidence intervals, and subgroup, meta-regression, and publication bias analyses were conducted for outcomes with significant pooled effects and heterogeneity (I2 > 50%). Dietary chicory increased FI (SMD = 0.420; 95% CI: 0.104 to 0.736; p = 0.009; I² = 94.29%) and BWG (SMD = 1.000; 95% CI: 0.718 to 1.282; p < 0.001; I² = 93.24%) and lowered FCR (SMD = -0.450; 95% CI: -0.660 to -0.240; p < 0.001; I² = 86.07%), relative to control diets. The inclusion level and growth stage moderated FI. Continent, inclusion level, form, and sex moderated BWG. Continent, inclusion level, form, route, and sex moderated FCR. Fail-safe numbers for FI (749), BWG (5,535), and FCR (770) all exceeded their robustness thresholds. Dietary chicory improves growth performance, supporting its potential as an alternative to antibiotic growth promoters. However, heterogeneity left unexplained by the tested moderators highlights the need for standardized dosing and reporting in future trials to enable commercial adoption.