Producing sufficient animal-source protein for the growing world population

The recommendation for macronutrient intakes by humans suggests obtaining 45-65% of the daily caloric intake from carbohydrates, 10-45% from fat, and 10-35% from protein. According to the Dietary Reference Intakes (RDI) issued by the Institute of Medicine of the US Food and Nutrition Board [8], adults need to eat about 60 g of protein per day. Protein that comes from animal sources is in general nutritionally more complete than protein that comes from plant sources, because it contains the essential amino acids in a more adequate pattern. Average meat consumption varies greatly between the developed and the developing world. Although levels of meat consumption are tending to stagnate in highly developed societies, a strong upturn is expected in emerging economies due to increasing urbanization and growing affluence. This chapter discusses the specifics of the current production of animal-derived protein, focusing on poultry meat and eggs, pork, beef, dairy, and aquaculture. The growing demand for animal-sourced protein is analyzed and possible means of meeting it presented, including improved breeding programs and various approaches to means of enhancing the nutritional intake and consequent performance of livestock. The chapter concludes with a consideration of the environmental concerns that must be addressed if the world's livestock population grows significantly in response to increased global demand for animal-source protein.