dunno how others do it.. but get the fury AA ability to charm... wait until you charmed pet dies.. get xp.. and immediatley mez the animal (AA ability right before charm for furies).. once mezzed charm new pet. I imagine coercers work the same cuz.. well.. they get mez and charm but as normal spells.
Also, You do NOT need to do dmg to the mob to get xp.. your pets small ammount of dmg before it dies will still get you full xp. the only time I do damage to the mob is when I first start out hunting (or die heh).. pull with a DD spell and then mez the mob.. and charm.. the click off the mez spell (pet isnt very effective if its is mezzed..) in your maintained spell bar.. voila!
If you need more help feel free to PM me.. i will help you out.. and can give u some pointers if u are a fury along with where furies can hunt heroic animals from 40-50 or so..