I wasn't sure if we would do them any harm by giving them carrots when they aren't used to eating them, so, one day, as we were going over we saw some men in the garden next to their field, we asked, well, I did with some assistance from Youngest, and they said, though they aren't their horses, that there would be NO problem at all.
Then the animals wouldn't come. D stood at the fence calling and whistling, and nothing happened....
Finally she thought of calling to them in Spanish, specifically, calling to them to 'come here'. Worked a charm. She called once, the heads all turned and in a body they headed over. Rather more than she'd hoped for.
The donkey is proving the brightest (or greediest) of the lot, arriving first every day and getting the most too.