  We investigate the equation of state of hadronic matter at finite values of
baryon density and temperature reachable in high energy heavy ion collisions.
The analysis is performed by requiring the Gibbs conditions on the global
conservation of baryon number, electric charge fraction and zero net
strangeness. We consider an effective relativistic mean-field model with the
inclusion of Delta-isobars, hyperons and lightest pseudoscalar and vector
mesons degrees of freedom. In this context, we study the influence of the
Delta-isobars degrees of freedom in the hadronic equation of state and, in
connection, the behavior of different particle-antiparticle ratios and
strangeness production.
