The fourth edition of Tom Hales book does not list Rabies vaccine.

The 4th Edition of Drugs in Preg. and Lactaion by Briggs has no information for breastfeeding but does note that both the human vaccine(now most commonly used) and the duck embryo have been reportedly used in pregnant women with no clear association with fetal problems related to the vaccine.

About this case:
Good points this was a "provoked" attack helping the sick cat counts as provocation even though she was trying to help the cat.

Bad points: the cat was acting sick to begin with and a bite that last 5 minutes is not the typical "'I'm defending myself" kind of cat bite.  You did not mention if the cat had had rabies vaccination.

Since rabies has a near 100% mortality if contracted the mother will need to get the shots if the animal tests positive(They test the brain tissue of the dead cat).  Since the rabie vaccine is a inactivated vaccine I would think  that the child could still nurse as long as the mother is well as the child cannot get active rabies from the mother who receives the inactivated virus vaccine.

Jon Ahrendsen MD. FAAFP, LLLI Medical Associate
Co-Chair of Iowa State Lactation Taskforce
215 13th Ave. SW, Clarion, IA 50525
515-532-2836  FAX 515-532-2523