Conference Feed Manufactures: p. 41-45.

influence of an unidentified factor found in fish THE high protein content of the horny tissues and keratinous areas has been recognized for some time. This protein material, feather, hoofs, horns, and hair, would appear to be nutritionally desirable. However, its low digestibility has in the past rendered it of little value as a feedstuff for most species. Annually over 50,000 tons of dry feathers are avail-able at processing plants. Recently much interest has been shown in the processing of waste feathers for utilization in poultry feeds. Very little interest was shown in early studies concerning hydrolyzed poultry feathers as feed supplements. Scott and Payne (1928) reported that hydrolyzed poultry feathers improved egg production in one year but not in the second year. 1 Published with the approval of the Director o