Phytase in the diets of broilers: technical-economic evaluation

The objective of this study was to evaluate the effects of phytase in broiler diets on zootechnical performance and nutritional cost through a technical economic analysis combined with a systematic review and meta-analysis.

A database was created by collecting scientific articles published between 2018 and 2023 that investigated broilers supplemented with phytase. The PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) flowchart was used to select the articles. A total of 3,483 publications were identified, of which 17 were selected. Performance data from the articles and qualitative factors (broiler strain, diets, and phosphorus reduction) were collected, tabulated, and used in economic equations. Meta-analyses were conducted to assess effect size, heterogeneity, and publication bias for performance variables among the groups positive control (DB) vs. reduced P diet without phytase (DRP), DB vs. reduced P diet with phytase (DRP+PHY), and DRP vs. DRP+PHY.

Seventeen studies were selected, totaling 16,151 broilers evaluated, with average initial and final weights of 44.0±2.0 g and 2,731±0.6 g, respectively, receiving 1,664 FTU/kg of phytase and a 0.15% reduction in digestible phosphorus. Overall, the results indicate that phytase supplementation improves broiler performance (p<0.05), whereas DRP without phytase impair it (p<0.05). These findings were reinforced by our meta-analysis, which identified a significant effect size (pSMD<0.001) for all variables studied, high heterogeneity among studies (p<0.001, I2 = 96%), with broiler strain sending as the main source of variation. No publication bias was detected across the evaluated variables. The broilers subjected to DRP+PHY had a lower cost/head and greater final weight than those fed BD and DRP, respectively. In addition, DRP+PHY reduced the feed cost per ton of broilers by -1.56%.

Reducing phosphorus in diets without phytase impairs broiler performance, while supplementing phytase in low-phosphorus diets improves performance and reduces nutritional costs, saving approximately US$9.52 per ton of broilers.