  We establish sufficient conditions for the existence, and derive explicit
formulas for the $\kappa$'th moments, $\kappa \geq 1$, of Markov modulated
generalized Ornstein-Uhlenbeck processes as well as their stationary
distributions. In particular, the running mean, the autocovariance function,
and integer moments of the stationary distribution are derived in terms of the
characteristics of the driving Markov additive process. Our derivations rely on
new general results on moments of Markov additive processes and
(multidimensional) integrals with respect to Markov additive processes.
