  We calculate the total internal energy, total energy density and pressure,
and the free energy for the neutrino and electromagnetic fields in Einstein and
closed Friedmann cosmological models. The Casimir contributions to all these
quantities are separated. The asymptotic expressions for both the total
internal energy and free energy, and for the Casimir contributions to them are
found in the limiting cases of low and high temperatures. It is shown that the
neutrino field does not possess a classical limit at high temperature. As for
the electromagnetic field, we demonstrate that the total internal energy has
the classical contribution and the Casimir internal energy goes to the
classical limit at high temperature. The respective Casimir free energy
contains both linear and logarithmic terms with respect to the temperature. The
total and Casimir entropies for the neutrino and electromagnetic fields at low
temperature are also calculated and shown to be in agreement with the Nernst
heat theorem.
