I have advised breeders in the past to do the following:
Keep queens (and toms) current by vaccinating against panleukopenia annually.
Allow kittens to nurse until 8 weeks - start them on canned and then kibble food as early as they are interested so that the weaning process at 8 weeks is minimally stressful.
Begin vaccination of kittens at 8 weeks, followed by more at 12 and then 16 weeks.
8 weeks: FVRCPC #1
12 weeks: FVRCPC #2, FeLV #1
16 weeks: FVRCPC #3, FeLV #2, Rabies
To avoid any exposure of the kittens to panleukppenia virus, do not allow any cats into the home who have not been vaccinated for it at least 1 week prior to entry, and do not bring any sick cats into the cattery.
The only cases of panleukopenia I have ever seen or even hears of in private practice have been in stray/homeless/shelter kittens that probably didn't nurse, or nursed from an unvaccinated mom, then came into a crowded, unsanitary situation full of unvaccinated animals. It's just not going to be an issue in a situation with owned and properly cared-for cats that is closed to outsiders.