  We consider quadratic three-dimensional differential systems having a Hopf
singular point. We study the cyclicity when the singular point is a center on
the center manifold using higher order developments of the Lyapunov constants.
As a result, we make a chart of the cyclicity by establishing the lower bounds
for several known systems in the literature, among them the Rossler, Lorenz and
Moon-Rand systems. Moreover, we obtain an example of a jerk system for which is
possible to bifurcate 12 limit-cycles from the center, which is a new lower
bound for three-dimensional quadratic systems.
