Some happy Bouvier puppies, aged somewhere between 7 and 9 weeks, playing in a children's wading pool. These pools with water in them are a fine way to introduce puppies to water and make them confident about playing in it. Most Bouvier naturally love to splash in water ! It's also a fine way to help them cool themselves in warm weather, but of course it is not a substitute for shade or for access into a cool house on hot days. Of course now you have wet puppies, so when you bring them back indoors you may want to confine them to the utility room or kitchen while they dry off.
 
Some breeders also use these pools as a whelping nest. They are cheap, urine-proof, easily cleaned and disinfected, and the edge is the right height to keep really young babies in while easy for the mamma bitch to get in and out as she needs to.
 
I don't know if you can really see this , but each puppy is wearing a different colored collar. (The leftmost puppy is wearing a pink collar and the one in the middle seems to be wearing lavender.) Good breeders color code their puppies early so they can identify each individually and thus keep careful records of physical and behavioral qualities. It also get the babies used to wearing a light collar as something normal and not to be distressed about.