We investigate the effects of non-valence contributions in the calculation of the electromagnetic pion and kaon form factors using the Poincaré-covariant Bethe-Salpeter and Dyson-Schwinger formalism. In this work, we study an extension of the widely known Rainbow-ladder truncation to include, to some extent, non-valence quark effects by introducing pions as explicit degrees of freedom in the Bethe-Salpeter interaction kernel and in the quark propagator. The obtained results for the absolute values compare favorably to the available experimental data, and they are analyzed in detail by confronting them to the expectations based on an isospin-symmetric version of a vector-meson dominance model.

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