NAIROBI, Kenya — “This is the spot,” said Morris Njeru, gazing down at a tangled patch of farmland where he recently found the bloody corpses of David, Mukurino and Scratch — his last donkeys.

Mr. Njeru, 44, a market porter who depends on his animals to ferry goods around this city, had already lost five donkeys earlier in the year. In each case, the thieves slit the animals’ throats and skinned them from the neck down, leaving the meat to vultures and hyenas.

Four months later, all Mr. Njeru could find of the animals was a single hoof, which he pocketed as a memento.

There are scant remains, too, of Mr. Njeru’s once comfortable life. Without his animals, his income plummeted from nearly $30 per day to less than $5. He can no longer afford payments on a loan for a small piece of property he rented, and he fears he will have to take his child from boarding school.