We are currently listening to Book 7, Harry Potter and the Deathly Hallows and we hear about thestrals, winged horses, being used as part of the Order of the Phoenix's effort to safely spirit Harry away from the Dursley's home. When they arrive the thestrals are allowed to hang out in the garden at The Burrow, the home of the Weasley family. There they are said to "browse" which when applied to animals means eat plants.
In volume 5, Harry Potter and the Order of the Phoenix, we first encounter thestrals. Later that year Rubeus Hagrid demonstrates that they are meat-eaters, and at the end of that year Harry, Hermione, Ron, Ginny, Luna, and Neville fly to London on thestrals which are attracted to them by the giant blood on the robes of Harry and Hermione.
Animals which Hagrid attracts by providing a half carcass of a cow, and later Harry attracts with fresh blood on his robe, such animals are carnivores. They won't "browse" on plants as is alleged in Book 7. Once again we see that Rowling's continuity editors dropped the ball.
