Wildfowl Breast Farming Guide.

I prefer farming these in Krasarang Wilds from carp hunters. They have a pretty good droprate (68%) and doesn't drop alot of junk. They're lvl 86 and have around 148k in health.
They usually drop soft down feathers which are just junk, and ornamental feathers. The ornamental feathers are also junk, they can't be used for anything, but they sell for 6g so just sell them to a vendor (one x20 stack = 120g) instead of throwing them away.
They also have a 5% chance to drop mote of harmony. 
Carp hunters can be find at the Dojani River, inside the red circle on the map.
They're on land, usually right next to the river.They can often be found fighting krasari huntresses which drops Raw Tiger Steaks. I wouldn't recommend farming Raw Tiger Steaks there tho.

You can also farm wildfowl breasts in Valley of the Four Winds from glade hunters and glade sprinters. The droprate is almost as good (64% and 63%), but it's usually alot more crowded there because it's right next to Halfhill where all the cookingtrainers and most rep NPCs are. Both of them have around 110k health but unlike the carp hunters in Krasarang Wilds, these are hostile against both Horde and Alliance.