Really sorry to hear about this happening to you. Many breeders are simply in the business of making money instead of actually looking out for the future generational health of the breed. Many vets also use Boxer health quirks to bilk money out of unsuspecting owners.
I'm not saying that either your Breeder or Vet did anything right or wrong, I have no way of knowing that. I just wanted you to be aware of that.
I tell everyone with a Boxer, or any dog really, to do your homework on anything and everything related to Boxers and their health and health issues. You practically need to become an amateur veterinarian in order to access whether the vet you're using is one of the good ones or a charlatan.
Knowing as much as possible will also help you weed out good breeders from bad ones. I'm not saying that it's foolproof but being informed, especially about Boxer health issues and quirks is extremely important.
Finally, if I hadn't convinced you yet to study up on Boxer health then maybe the following will. If you know about their health issues and health quirks then you'll be more likely to see the signs of a potential health problem based on symptoms while it can still be treated with minimally invasive procedures or medicine regiments. Trust me, it's always better to notice the signs of a health issue early on in it's progression than later.
So just to finish up, I don't know if the breeder is a charlatan or if the vet is a charlatan so I recommend not jumping to conclusions. This is a very emotionally charged issue for you, as it would be for me or anyone else on this board, and it's important to take a deep breath, count to ten and look at the information as objectively as possible.
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