Assessing the potential use of a feed additive based on biochar on broilers feeding upon productive performance, pH of digestive organs, cecum fermentation and bacterial community

•Biochar affected negatively performance traits at the starter period in broilers.•Biochar improved performance at the grower period and for the entire cycle in broilers.•Biochar increased acetic and caproic contents in broilers cecum.•Biochar did not affect richness and diversity of cecal microbiota.•Biochar affected some bacterial taxa related with improved efficiency.