Enables branched-chain-amino-acid transaminase activity. Acts upstream of or within branched-chain amino acid catabolic process. Located in cytosol. Is expressed in several structures, including alimentary system; craniocervical region bone; limb; nervous system; and sensory organ. Orthologous to human BCAT1 (branched chain amino acid transaminase 1). [provided by Alliance of Genome Resources, Apr 2022]