Three year old bichons? They are nowhere near being senior - my Westie just got his first senior wellness check and he's 7 years of age. What is your vet thinking?
A what? Maybe, I'm stupid but I've never heard of this. Is your vet in need of more money or something. Your dogs are adult dogs now not by any means senior. And my 12 yr old Lab doesn't get blood work unless there is a need (symptoms) for it. Get a new vet, your dogs just need a check up at age 3.