Can they? Yes. Should they? Probably not. Although not that different ingredient-wise than adult formulas, puppy-specific kibble usually has more fat and protein.The meat sources are likely listed first (ie, in higher proportion) for a growing body, which obviously makes it more appealing to an adult dog. The high protein and caloric content can make adult dogs overweight super quickly, so there's a reason the packaging says to only feed to the lil ones for a limited time — that meal for an extended period of time is damaging and dangerous to health.
In fact, some breeders of large dogs (especially those prone to weight issues or bloat) recommend not feeding these puppy formulas more than a few months due to the high content of all those things mentioned above. Did you feed your pets puppy food or move straight into adult bits for the babes?
Source: Flickr User estoril