VET TATTOO PRACTICES

I have recently found out that Veterinarians do not change their needle after tattooing each animal. They are trained to clean and sterile the needle and simply put it away until the next time it is needed. With humans, the needle is changed after each person. Does this current veterinarian practice of never changing the needle create any issues for the animal besides being inhumane?

[Aleda M Cheng, D.V.M., C.V.A]

Tattooing is mostly performed in large animal medicine for identification purposes.  A stamp is used, not a needle.  

Tattooing is uncommon in small animal medicine and has largely been replaced by microchips, except in service dogs and racing greyhounds and such, but I assure that when performed it is done with a sterile prep and instruments.  It is no less humane than humans getting tattooed.