She should be at least 3 years old, 6ft+ and well muscled.

Sure you could breed her, but I wouldn't just breed her to any male you can throw at her. Think it through and get her a worthy male you really want to pair her with.

It's not too late to breed her this year, but I would just wait. I would give her this year to pack on a few more pounds and age a bit more. She'll reward you with a better litter next year and will recover nicely.