Can models exported as mesh in Rhino be used for rigging and animation in C4D or other softwares?
wait… maybe yes?
ok yes… but which answer would you like to hear? this can only be answered with unrolling ones complete knowledge about it.
if you know how to set up the export you can get some decent meshes, that of course depends entirely on how complex your model is. the mesher from rhino straight out of the box is not one of the best, but there is an interesting attempt to get this into alignment for the next major release.
getting rough geometry out which you might not have to fix much and use a hypernurb (aka subd) in c4d on, is probably also better than trying to get a highly complex polysurface into a workable mesh. generally if you have to create smooth animations with a lot of stretch in the geometry, then creating the polygons manually will be inevitable. this can be maybe done in rhino but i would not recommend it, since working on mesh is far more advanced in c4d of course.
another option is if you have simple single surface nurbs you can export them as iges which can be read in c4d as nurbs. i didnt have much luck trying to get polysurfaces into cinema a lot of rework which i never attempted, so dropping the issue. i also have no experience animating with nurbs which might be interesting.
under the line you can do anything depending on the amount of effort you are willing to invest, but if you are into serious character animation then rhino may not be your first choice unless you have a good workflow bringing the advantages of each software into play.