I just came across this ethnic group in China that forbids the eating of dogs.
https://en.wikipedia.org/wiki/Mosuo
While some Asian cultures practice the custom of eating dogs, this is strictly forbidden to the Mosuo. In Mosuo culture, a myth describes that long ago, dogs had life spans of 60 years while humans had life spans of thirteen years. Humans felt their life span was too short, so they traded it with the dogs in exchange for paying homage to them. Therefore, dogs are valued members of the family. They are never killed, and they most certainly are never eaten. During the initiation rites into adulthood, Mosuo adolescents pray before the family dogs.