  We explore the use of two criteria to constraint the allowed parameter space
in mSUGRA models. Both criteria are based in the calculation of the present
density of neutralinos as dark matter in the Universe. The first one is the
usual ``abundance'' criterion which is used to calculate the relic density
after the ``freeze-out'' era. To compute the relic density we used the
numerical public code micrOMEGAs. The second criterion applies the
microcanonical definition of entropy to a weakly interacting and
self-gravitating gas evaluating then the change in the entropy per particle of
this gas between the ``freeze-out'' era and present day virialized structures.
An ``entropy-consistency'' criterion emerges by comparing theoretical and
empirical estimates of this entropy. The main objective of our work is to
determine for which regions of the parameter space in the mSUGRA model are both
criteria consistent with the 2$\sigma$ bounds according to WMAP for the relic
density: $0.0945<\Omega_{CDM}h^2<0.1287$. As a first result, we found that for
$A_0=0$, sgn$\mu=+$, small values of tan$\beta$ are not favored; only for
tan$\beta\simeq50$ are both criteria significantly consistent.
