This is my 12-year old pup, Tuffy (Tuff-Stuff-La-Rue). He LOVES tennis balls. Fetching them, chewing on them, which we try not to let him do, and just carrying them around...
While many people think dogs see everything in gray, turns out our furry friends can actually see blues and yellows...but they are red-green colorblind.
This means dogs have a hard time identifying things that are red from the grass when they're playing in. A blue or yellow toy can be seen much easier!
Research recommends that if you’re playing with a toy outside, definitely go with blue, which will create a good contrast in the grass. If you’re playing inside, you have a little more wiggle room and can go with any colors your dog's able to see—like blue, yellow, or even purple!