i don't believe that you have to spay a bitch for that reason.our field bitches can NOT be spayed if they are competeing in a AKC Field Event.i have pedigrees from 1963 to the present and only one of the bitches died from this type of cancer,maybe.she did have cancer but i don't now what it was and this was just last year(my father's dog).i think it was more from her bloodlines,Genetics i feel is more of a cause of cancer,if it is prevalent in the bloodlines maybe those lines should not be bred.Environment could also be a factor, i don't recall reading any of these things mentioned.when is the last time anyone has had there water tested? house tested for Radon? sprayed any thing on your lawns lately!!! it is a good story,but i'm a little skeptical.A lot of Anti-Hunters and Vets don't think like i do and feel that i should not use and BREED my dogs for what they are bred to do!! Now my brittany's dam died of this type of cancer,which was not caught by her owner.this is where a GOOD BACKYARD BREEDER like myself makes a mental note.2 years later my Britt gets a lump from out of nowhere and big real fast,2 months after her yearly check up.(remember my mental note!!) my wife and i checked her bi-monthly for 2 years b/4 this happened so we were looking for it to happen.cancer was removed and she was spayed at this point.2 yrs.later at 12 years of age the only reason why she no longer hunts is she is losing her hearing,but other than that she is fine.oh and i never bred her either.