R. Bras. Zootec.28/ago/2026;55:e20250119.
Black wattle (Acacia mearnsii) tannins in broiler diets: intestinal health, bone quality, nutrient digestibility and performance
Felipe Dilelis
, Túlio Leite Reis
, Carlos César Machado Miranda
, Amanda de Moraes Bravo
, Ednaldo Fernandes Guariento
, Greicy Sofia Maysonnave
, Noedson de Jesus Beltrão Machado
, Cristina Amorim Ribeiro de Lima
ABSTRACT
This study evaluated increasing dietary levels of Black wattle bark extract (BWE) on broiler performance, nutrient digestibility, intestinal histopathological score, and bone quality. A total of 240 male Cobb 500 broilers, eight days old, were distributed into five dietary treatments (0, 300, 500, 700, or 900 mg kg−1 BWE) in a randomized block design, housed in metabolic cages, with eight replicates of six birds each. Performance was evaluated from 8 to 28 days of age, nutrient digestibility from 18 to 20 days, and intestinal and bone parameters were assessed at 21 days of age. Supplementation with BWE up to 500 mg kg−1 increased crude protein digestibility (5.36%) and ash retention (16.70%) without negatively affecting growth performance. However, the 900 mg kg−1 dose reduced feed intake (6.14%) and weight gain (6.4%). In addition, birds fed 300 mg kg−1 BWE showed reduced jejunal inflammatory cell infiltration compared with those fed 900 mg kg−1. These findings indicate that moderate supplementation (300–500 mg kg−1) enhance intestinal morphology, and nutrient utilization, while excessive inclusion compromises productive performance. In conclusion, BWE represents a promising natural feed additive for broilers. However, its use should be limited to moderate levels to avoid detrimental effects on growth performance.
Palavras-chave: condensed tannins; gut morphology; mineral retention; protein digestibility