META-ANALYSIS OF THE HYPOCHOLESTEROLEMIC POTENTIALS OF TURMERIC (CURCUMA LONGA) IN BROILER CHICKENS

The purpose of this experiment was to use a meta-analysis approach to resolve conflict, identify knowledge gap and develop new insights on the effect of turmeric on plasma total cholesterol (TC), high-density lipoprotein cholesterol (HDL-c) and low-density lipoprotein cholesterol (LDL-c) concentrations in broiler chickens. The authors found 64 studies following a systematic search conducted in 3 electronic databases and the World Wide Web using several search queries. Eighteen out of the 64 publications met the predefined eligibility criteria to assess the impact of turmeric on plasma TC, HDL-c and LDL-c concentrations in broiler chickens. Data collected were analysed in OpenMEE software and pooled estimation revealed that turmeric-based diets significantly reduced the concentrations of TC and LDL-c (p<0.01), and improved the concentrations of HDL-c (p<0.01) in chicken blood when compared to those on the control diets. Sub-analysis found significant associations between covariates (chicken strain, supplementation level, number of birds per treatment and duration of supplementation) and measured outcomes (TC, HDL-c and LDL-c). Significant heterogeneity (I-2) existed in the meta-analysis, and meta-regression analysis found that chicken strain and duration of supplementation were predictors of HDL-c and LDL-c, and explained 72% of the sources of heterogeneity among the studies used in the meta-analysis. The results of the present meta-analysis showed the potential of turmeric-based diets to modulate the production of blood cholesterol in broiler chickens.