A meta-analysis of 35 trials to evaluate the effect of a microencapsulated feed additive based on botanicals and organic acids on broiler performance

Homeostasis is essential for maintaining a healthy gut. Disruptions to this balance are triggered by many causes, such as feed antigens, dysbacteriosis, and heat/cold stress, and have adverse consequences on animal growth performance. In such circumstances, dietary energy and nutrients are diverted to support the immune response and restore intestinal homeostasis. Gut health feed additives are tools designed to support poultry during stressful conditions, but it is fundamental to assess their robustness in different rearing conditions.

This study evaluated a microencapsulated feed additive based on botanicals and organic acids (AviPlus®P) on growth performance of broilers. The database included 35 trials performed in research centers or commercial farms over 13 years (2009-2022), in 11 countries (EU and extra-EU), with different genetics (Ross308, Ross708, Cobb500, Hubbard) and nonmedicated diet formulations based on wheat/corn/barley and soybean for a duration of 34-48 days. FA was supplemented on top of the standard diet in a range of 200-500 g/MT. Feed conversion (FCR) was standardized according to the Aviagen guidelines (-0.01 FCR for each extra 50 grams of final body weight, FBW). Data were analyzed with SPSS 30.0: the meta-analysis was performed with the Unstandardized Mean Difference and the REML method, while EPEF data were analyzed with T-test, and correlation with Pearson coefficient.

Compared to control, the FBW of broilers supplemented with AviPlus®P was increased by 38 grams (2504 vs 2466 grams, p=0.009), and positively correlated with AviPlus®P intake (p=0.02). FCR was improved by 4 points (1.70 vs 1.74, p=0.001). EPEF was 344 in the AviPlus®P group and 335 in control group (p=0.59). The improvement of growth performance might be related to the multifactorial mechanism of action of AviPlus®P. Previous studies demonstrated AviPlus®P ability to improve the intestinal barrier integrity, reduce inflammation, modulate gut microbiota, and increase nutrient absorption and digestibility of chickens.

In conclusion, this study validated the positive effects of AviPlus®P on growth performance of broiler chickens under various rearing conditions. This highlights how the intestinal multifaceted benefits of FA might be translated.