Mine get their first innoculations at 14 and 16 weeks( Maternal antibodies may be still active up to 16 weeks) and then No Boosters. My vet years ago told me that it was not necessary, especially for dogs that are mixing with others (shows etc) as they build up a natural immunity. Also because I have heard of too many whippets that have suffered from auto-immune disease after boosters. I feed a natural diet (BARF) as far as possible, and it seems to work. The only dog I ever lost with parvo was innoculated against it. The boarding kennels thing is admittedly a problem, but mine either go to friends or stay at home and get looked after there. (I am lucky in having excellent doggy neighbours)