A Comprehensive Meta-Analysis of Haemato-Biochemical Parameters in Chickens Across Different Ages and Study Durations

Abstract

Background: Haemato-biochemical parameters are pivotal indicators of health and physiological status in poultry and are influenced by various factors, including age and experimental conditions. Understanding these parameters is essential for improving poultry management and health diagnostics.

Objective: This study aims to systematically evaluate the effects of age and study duration on haemato-biochemical parameters in chickens, integrating data from diverse research studies to establish comprehensive reference values and identify potential trends.

Methodology: We conducted a meta-analysis using the OpenMeta(Analyst) software, selecting peer-reviewed studies that reported haemato-biochemical values in chickens. Age of chickens (in days), number of chickens taken as a study sample, and number of days of study were the primary variables extracted. Random-effects models were employed to account for between-study variability, and forest plots were generated to visualize individual and pooled estimates with 95% confidence intervals (C.I.).

Findings: The meta-analysis included 30 studies, with a cumulative sample size exceeding 5,700 chickens. The forest plots revealed significant heterogeneity among studies (I^2 > 50%), with the age of chickens showing a wide range of effects on haemato-biochemical parameters. The overall effect size suggested that older chickens tend to have higher variability in these parameters. Furthermore, larger study samples and extended durations were associated with more precise estimates, indicating the importance of study design in haemato-biochemical research.