Who fed Black Beauty when he was young?

The first few chapters of Black Beauty describe Black Beauty's early years as a young colt. He was born and brought up in a beautiful meadow with a kind master and a mother who doted on him. In those early years, he says, "I lived on my mother's milk." As he got older and his mum left him during the day to work, he ate the meadow grass. He was looked after by a stable hand called Old Daniel, though he doesn't say whether Daniel fed him or not. When he is four, his master breaks Black Beauty in preparation for selling him, rewarding him with oats when he does well.
In chapter three, Black Beauty moves to a place called Birtwick Park, where he is looked after by a man called John Manly. Black Beauty says that a groom comes into his box to feed him oats. Another time, Black Beauty and another horse called Ginger eat the sweet apples that are lying on the floor of the fields just outside their stables.