19.4%. Chicken has a higher protein content than duck, with chicken averaging about 19.3% protein and duck averaging about 15.5% protein. The protein content of chicken lungs from chicken breast meat is about 19.4%. Chicken lungs are the main respiratory organs of chickens, usually need to filter the air through the chicken lungs, chickens usually live in a poor environment, easy to grow and develop in the process, infected with avian influenza virus and many other viruses.