  We discuss influences of bulk viscosity on the Early Universe, which is
modeled by Friedmann-Robertson-Walker metric and Einstein field equations. We
assume that the matter filling the isotropic and homogeneous background is
relativistic viscous characterized by ultra-relativistic equations of state
deduced from recent lattice QCD simulations. We obtain a set of complicated
differential equations, for which we suggest approximate solutions for Hubble
parameter $H$. We find that finite viscosity in Eckart and Israel-Stewart
fluids would significantly modify our picture about the Early Universe.
