Response of turmeric powder supplementation on commercial laying hens performance: a meta-analysis

Turmeric powder (TP) is considered an alternative to growth promoter antibiotics in layer diet. The objectives of this meta-analysis were to assess the effectiveness of supplementation with turmeric powder on feed intake (FI), hen day production (HDP), feed conversion ratio (FCR), egg weight (EW), and egg mass (EM) of laying hens. Peer-reviewed randomized controlled trials (RCTs) published in English were found using databases such as PubMed, Scopus, Science Direct, and Google Scholar. The meta-analysis required information on moderators (age of the hen at the start of the intervention, inclusion level, and turmeric powder treatment duration), a sufficient description of randomization, performance data, and associated measures of variance such as standard deviation (SD) or standard error (SE). All analyses were carried out using the Open Meta-analyst for Ecology and Evolution (OpenMEE) program. Data from the 17 studies included in the meta-analysis were pooled and presented as standardized mean differences (SMDs) at a 95 confidence interval (CI) using a random-effects model. Results indicate that dietary TP supplementation reduced FI (SMD=-0.28 g; 95 CI:-0.69 to 0.13) and FCR (SMD=-0.70 g; 95 CI:-1.37 to -0.028) and increased HDP (SMD=1.09; 95 CI: 0.59 to 1.59), compared with the controls. In contrast, egg weight and egg mass were not significantly different from controls. Restricted subgroup analysis indicated that chosen moderators (age of hen, inclusion level, and supplementation duration) influenced the results of this meta-analysis. The meta-analysis explains that turmeric powder is an ingredient that could be used as a feed additive in laying hens to increase egg production. © 2023 Fundacion CIPAV. All rights reserved.