Physical characteristics of feathers play a role in feather eating behavior

Feather pecking is positively associated with feather eating in laying hens; however the criteria of the birds for pecking, plucking, and eating feathers has not yet been systematically examined. In the present study, we investigated if laying hens show preferences for feathers of different lengths and regions. Twenty Lohmann Selected Leghorn hens with a high feather pecking activity were used in the present experiment. Ten birds were individually given access to 4 plastic elements, each perforated with 4 feathers 2, 4, 6, or 8 cm in length (i.e., 1 flat piece of plastic for each feather length). Another 10 hens were given access to 3 identical plastic elements, each perforated with 4 pieces of feather 2 cm in length from the calamus (part of the shaft closest to the bird body), middle (shaft with outer and inner vane), or tip (part of the shaft with vane furthest from bird body) of the feathers, respectively. The number of feathers of different lengths and regions plucked and eaten from each plastic element was recorded. Birds were tested over a period of 10 d on a daily basis. Laying hens preferred shorter feathers over longer ones. A rank ordering of preferred feather regions from the most to the least important using the number of pieces eaten gives a sequence of the tip, middle, and calamus of the feathers. The results clearly show that physical texture or appearance, or both, of feathers plays a role in feather pecking-eating behavior in laying hens.