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Observations in cosmology and astrophysics indicate that about $84$% of the matter in the Universe, the so-called dark matter, is non-baryonic, non-relativistic, and does interact only through gravity. [@darkmatter; @dmschumann; @dmsalati; @pdg2012].

These observations involve the internal dynamics of galaxy clusters [@galclust], the rotation curves of galaxies [@galrot], weak lensing [@bulclust], also the Cosmic Microwave Background (CMB) from which the relic density of cold dark matter (CDM) in the Universe is at present deduced to be $\rm \Omega_{CDM}h^{2} = 0.1199 \pm 0.0022$ (Planck+WMAP) [@planck2015; @wmap7yr].

A common assumption is that dark matter is made of Weakly Interacting Massive Particles (WIMPs) that form halos in which the visible baryonic part of galaxies is embedded. There are a variety of candidates for WIMPs, among which those provided by theories based on supersymmetry (SUSY) attract a great deal of interest. In some classes of minimal supersymmetric (MSSM) and minimal universal extra-dimensional (mUED) extensions of the Standard Model (SM), the lightest particle (LP) is stable thanks to the conservation of a model-dependent parity that forbids its decay into SM particles. Consequently, these LPs can only annihilate in pairs, making them a possible WIMP candidate for dark matter [@lsp; @lkp]. In these models, secondary 