You can import and export individual animation layers, or hierarchies of animation layers.
The layer node, its animation curves, and its blend nodes are exported as a Maya file. Any models with attributes associated with the layer are not exported.
To export a hierarchy of animation layers
All of the layer nodes, animation, and blend nodes are exported, and the structure of your layer hierarchy is saved.
To import an animation layer or animation layer hierarchy
After you have exported a layer or layer hierarchy, you can import it into another scene.
In order to play the imported layer’s animation, your scene must contain the same objects and attributes (by name) as those on the imported layer. If the scene does not contain the same objects and attributes, the imported layer animation cannot be properly connected in the dependency graph, so it has no affect on the result animation in your scene.