  We investigate relative hadron yield production of various like and unlike
mass particles in ultra-relativistic heavy ion collisions by employing a
statistical thermal model with finite-sized baryons (antibaryons) to imitate
the hard-core repulsive interactions leading to the excluded volume type
effect. A strong evidence of strangeness suppression relative to the
non-strange ones, mainly pions, particularly at higher energies is also
observed. This study also indicates that at chemical freeze-out the particle
ratios and strangeness suppression in the system obtained theoretically are
sensitive to baryonic (antibaryonic) hard-core radius ($r_B$). A comparison
with earlier analysis involving the strangeness suppression effect is made
where baryons and antibaryons were treated as point-like particles. The
available experimental data showing energy dependence of various particle
ratios are well described throughout the range of centre-of-mass energy
($\sqrt{s_{NN}}$). The value of hard-core radius between 0.76 to 0.79 fm is
found to fit the data quite well using $\chi^{2}$ minimization technique. Two
different chemical freeze-out stages are found where the earlier one belongs to
baryonic (hyperonic), antibaryonic (antihyperonic) states and the later one to
mesonic degrees of freedom.
