This volume provides practical information on all the options currently available for the utilization of fish that are unsuitable for direct human consumption. The many by-products dealt with include fertilizers, animal feeds, protein concentrates for various food processes, pet food, feeds for fish farming, insulin, pearl essence, glue, gelatine, many biochemical and pharmaceutical products and chitin, as well as oils for use in paint, leather treatment, lubricants and putty, caulking compounds, greases and water repellents. The book is an introduction to a major world industry, and is written for a wide range of readers: fishermen, merchants, processors, animal feed manufacturers, businessmen, research workers and administrators.