  We consider perturbations of dynamical semigroups on the algebra of all
bounded operators in a Hilbert space generated by covariant completely positive
measures on the semi-axis. The construction is based upon unbounded linear
perturbations of generators of the preadjoint semigroups on the space of
nuclear operators. As an application we construct a perturbation of the
semigroup of non-unital *-endomorphisms on the algebra of canonical
anticommutation relations resulting in the flow of shifts.
