@#4: It is indeed. Middle English sprenkle, G sprenkeln, akin to OE sprengan (causative of springan (sprengan is also Althochdeutsch).
As sprengen is the causative of springen (to make spring) in G, as Nach-t-Gucker told us, the DWDS example die Lippizaner sprengten in die Manege is very strange as horses are the object of the action, not the subject (as here). When I read Robert's "ein Ross sprengen" I also thought, no, you can't say that. And I looked it up.
Grimm says: reitthiere als object ein Pferd sprengen ... die durch auslassung des objects hervorgerufene, jedoch nur scheinbare intransitive verwendung vgl. unter III. ... [dort a) examples without object and] den übergang von dem transitiven gebrauche zu dem intransitiven machen die folgenden wendungen deutlich: mit dem Pferde sprengen ... usw. Grimm adds, however, that the "intransitive gebrauch" made it possible that the "reitthier" could become the subject of a sentence with sprengen (whereas "springen" was the sandard verb for those cases), but finds only very few examples, some of them ambiguous.
Brockhaus/Wahrig, Duden Universal, Wahrig agree. Not a single example with horses as subjects, only riders. Brockhaus/Wahrig adds that you always need a direction as well. You can't say Der Kavallerieleutnant sprengte die ganze Nacht lang.
I wouldn't hesitate to call the DWDS-example non-standard German.
As far as Robert's example "ein Ross sprengen" is concerned, that was still used in Middle High German. According to Grimm, there are very rare examples left in the beginning of the 19th century, citing Schiller.
In modern German you don't say "ein Pferd/Ross sprengen", you use what Grimm calls a "scheinbar intransitive verwendung", even if you write a historical novel full of horsemen.
P.S.: And if you think "den Rasen sprengen" is funny what do you make of Schiller's "Der König fragte darauf den Kardinal von Lothringen, ob er keinen andern Grund gehabt, ihn in den Rath zu sprengen, als diesen?" (after the Cardinal had asked the King to join the council and then and there told him why). Quite literally: "springen lassen".