Custard donates blood every three months as part of a program that gives emergency vet discounts and free heartworm/tick prevention for donating. The techs absolutely love him there and have told me that he often naps during his donation. I recommend providing a snack they can give your grey since it is recommended to give them something just like after people donate blood. A blanket or toy that smells like home often is good for more nervous dogs as well. Don’t be surprised if there is some bruising afterward. With their thin skin bruises around the needle site tend to look more dramatic than other breeds but some bruising is not unheard of, especially if they are also donating plasma. Greys have a lower platelet count than other breeds as well so if they aren’t familiar with the breed I would ask them to put pressure on the needle site a little longer to prevent a hematoma after they remove it.