Does it wash?

Can you wash your dog too much? This wonderful weather has meant my two Springers (aka the mud monsters) come back caked in dirt and I’ve been both hosing them down and bathing them on particularly dirty days using dog shampoo.

Thankfully they enjoy bath-time, so its not a struggle, but I’m worrying whether washing them with shampoo several times a week might be damaging their coats or skin?
Anne Owen, by email