carabao(water buffalo)they are docile usually,,they harness them and use for working in the rice fieldshttp://www.outdoorbasecamp.com/forum/members/lefties/albums/philippines/1561-p10809191/
http://www.outdoorbasecamp.com/forum/members/lefties/albums/philippines/1566-full-951-59110-new-bolos-batangas-006/i carry one of these in the bush and jungle.
many variables in that question. Ability of rider,temperament and build of horse etc. Only attempt it if your child has good balance,,riding skills etc.