Why should you shake feather filled duvets?

Feather-filled bedding such as feather ticks, duvets, pillow, etc. collect dust (and dust mites). They also tend to clump, especially if exposed to liquids or any kind of moisture. Feathers also break down and the quill sections can get stuck partly through the fabric.

Historically (up through the late 1800s), most families had feather tick mattress over thick ropes, boards, or hard springs. At least once a year, the women took the feather ticks, quilts, and rugs out of the house and beat them with sticks. Later, they used a hand held beater that looked like a long tennis racket, made of metal strips or wires through the center. The cleanings took many hours, as dust was beaten out, clumps re-distributed throughout the fabric, and the items were left to air in the sun. Repairs were made for any holes or thread-bare fabric areas and then the beds were re-dressed before nightfall.