I'd say 3.5 based on that one photo. There isn't enough there for me to venture a score though. As far as whether to shoot or not, that's your call but I certainly wouldn't be critical of the decision to kill that deer. He's a nice buck. But, he'll be even better in another year or two.
Walk the night, travel light, cross the Rio Grande
Someone strums a mandolin, soft gulf breezes blow
My new life is waiting in old Mexico
-Robert Earl Keen