  We study anisotropic reheating (entropy production) on 3D brane from a
decaying bulk scalar field in the brane-world picture of the Universe by
considering off-diagonal metrics and anholonomic frames. We show that a
significant amount of, in general, anisotropic dark radiation is produced in
this process unless only the modes which satisfy a specific relation are
excited. We conclude that subsequent entropy production within the brane is
required in general before primordial nucleosynthesis and that the presence of
off-diagonal components (like in the Salam, Strathee and Petracci works) of the
bulk metric modifies the processes of entropy production which could
substantially change the brane-world picture of the Universe.
