  We study the role of the meson cloud on the electromagnetic transitions from
decuplet ($B'$) to octet ($B$) baryons in terms of the squared four-momentum
transfer $q^2$. In the quark model framework, the meson cloud dressing of the
quark cores gives important contributions to the $\gamma^\ast N \to
\Delta(1232)$ transition form factors. In the present work, we estimate the
meson cloud contributions of all decuplet to octet baryon transitions
($\gamma^\ast B \to B'$ or $B' \to \gamma^\ast B$). Models that combine valence
quark effects with pion and kaon cloud dressing provide a fair description of
the radiative decays of decuplet to octet baryons, namely the $\Sigma^0(1385)
\to \gamma \Lambda (1116)$ and $\Sigma^+(1385) \to \gamma \Sigma^+ (1193)$
decays. Previous studies indicated the relevance of the pion cloud effects on
the $B^\prime \to \gamma^\ast B$ transition, but also suggested that the kaon
cloud contributions may be important in the timelike region. We combine then
the contributions of the bare core, estimated by a covariant quark model, with
$q^2$-dependent contributions of pion and kaon clouds. We use the framework to
calculate the Dalitz decay rates and the Dalitz decay widths of decuplet
baryons in octet baryons with di-electrons ($B' \to e^+ e^- B$) or di-muons
($B' \to \mu^+ \mu^- B$). We conclude, based on the magnitude of our results,
that most estimates of the $B' \to e^+ e^- B$ Dalitz decay widths may be tested
at HADES and PANDA (GSI) in a near future. We discuss also the possibility of
measuring the $\Delta (1232) \to \mu^+ \mu^- N$ and $\Sigma^0 (1385) \to \mu^+
\mu^- \Lambda (1116)$ decay widths in some facilities, based on the estimated
branching ratios.
