Every Dog breeder should have his own identification number that should be included on microchip IDs

I think a big problem with shelters, homeless pets, etc. is nobody knows where these pets came from. Dead animals are found every day. Everyone talks about microchips, and they are only useful if the owners information gets updated after selling the pet or giving it away.

I do not understand that dog breeders don't get a unique identification numbers, and each puppy that gets sold has a chip with that identification number that can't be changed!

So no matter where that dog, cat goes. Owners information changed on the microchip or not. People would always know, what breeder sold the dog/cat.
And the breeder would have all the information from the first person that buys that puppy.

Also, I think it would be good if anyone that sells a dog or puppy, especially breeds like Pitbull, Bulldog, Rottweiler, etc. should fill out a puppy or dog questionary. With questions about why wanting this dog breed, have experience with this kind of breed, dog training and more.

There should be a Special commitment between the Breeder and the Buyer in bills of sales! Do a 2-week trial where the future pet owner and breeder agree to see if the puppy fits into the family and if the family is the right one for the puppy. Too many dogs get sold and end up on Craigslist or somewhere else with the words:" We got this cute puppy a week ago, but he/she doesn't fit in our family. I only want what I paid for it!"

And that's where all these dirty and crazy animal abuser lurk for new victims.
It should be a law in every contract that no matter when and for what reason the new owner can't keep the dog, has to bring the dog back to the breeder!