Scientists develop technology for converting feathers into feed-grade meal

Feathers, which account for around 5% of the total weight of poultry, represent one of the most significant waste streams in the poultry industry, Amir Maimandipour, one of the scientists behind the project, said.

Iran’s poultry industry is growing

“Poultry industry expansion [in Iran] means that more volume of this waste is generated, which requires its management and conversion into products with higher added value,” Maimandipour said.

Despite ongoing challenges with feed supply, the Iranian poultry industry experienced a significant rebound in 2024 following several years of turbulence. Monthly production reached 223,000 tonnes, allowing Iran to return to net exporter status, primarily to Iraq.

Currently, poultry feathers are occasionally used as a low-nutritional-value source of feed protein in the livestock industry, although they are commonly treated as slaughterhouse waste. New technology promises to substantially improve the existing feeding practices.

A new approach for feathers

The key obstacle to using feathers in animal feed is that a significant share of the feather protein is keratin, a fibrous structural protein that also forms the protective outer layer of skin, hair, nails, feathers, horns, and claws in animals.

There are numerous disulfide bonds in the keratin structure, which makes this protein insoluble and difficult to digest, Maimandipour said.

Despite this, keratin has the potential to be used beyond animal feeding. Keratinases have previously been isolated from microorganisms such as fungi, a number of bacteria, and Streptomyces. These enzymes have found many applications not only in wastewater systems but also in recent years in industries such as food, clothing, medicine, and cosmetics, Maimandipour said.

The researchers isolated the gene encoding keratinase from a native bacterial strain and expressed it in a laboratory host to study its enzymatic properties. According to Maimandipour, the strains can be applied directly for enzyme production or used alongside feather waste collected from slaughterhouses to facilitate the conversion process.

Scientists anticipate that the feather meal could enhance animal diets, but further research is essential to confirm its effectivenes.