Impact of phytase supplementation on performance and egg quality traits in broiler breeders: A meta-analysis

This meta-analysis aimed to determine the effect of phytase (PHY) supplementation on performance and egg quality traits in broiler breeders. A systematic review across multiple databases identified 2,162 studies, of which seven met all eligibility criteria and were included in the analysis. The meta-analysis compared egg production (EP), hatchability, fertility, egg weight (EW), and the yolk, albumen, and shell weight ratios relative to EW between diets supplemented or not with PHY. Heterogeneity and publication bias were also assessed. Overall, PHY supplementation significantly increased EP by 4.85 % (P < 0.01) and yolk ratio by 0.24 % (P < 0.05), while decreased EW by 0.53 g (P < 0.01) and albumen ratio by 0.34 % (P < 0.01). No significant effects of PHY were observed on shell ratio, hatchability, or fertility (P ≥ 0.05). Meta-regression and subgroup analyses revealed that PHY effects on EP were enhanced in diets containing ≥2.5 g/kg phytate phosphorus (PP) and calcium below requirements, particularly during the late production phase. In contrast, PHY reduced EW more remarkably in diets with PP ≥2.5 g/kg, vitamin D < 3,000 IU/kg, and non-phytate phosphorus below requirements. Additionally, yolk ratio increased significantly when PHY was fed for ≥10 weeks and when vitamin D levels were below 3,000 IU/kg. PHY affected shell ratio only in diets with PP levels <2.5 g/kg. An economic model based on the meta-analysis results indicated that PHY supplementation reduced EP costs by $0.011 or 3.1 % per egg, corresponding to an additional 5.9 million eggs per million broiler breeders. Overall, PHY supplementation improved performance and egg quality traits, offering measurable economic benefits for broiler breeder production systems.