Pleeeze read this list of suggestions from Dogster on protecting our pets from the sun. Some dogs are serious sunbathers, and could happily fry themselves for hours. But don't let them sizzle!
Dogs that worship the sun while lying on their backs risk developing tumors on the inguinal area, that vulnerable stretch of skin where the belly and hind legs meet; this area is unprotected by hair even on furry breeds. When you notice your sun-worshipping Spot panting, it's time to bring him back indoors before he sustains a sunburn. Please take extra precaution if your dog's snout is pink. Light-skinned dogs, like light-skinned people, are more prone to sun irritation.