Nutrition encompasses research with swine, poultry, beef cattle, dairy cattle, sheep, dogs, cats, and laboratory rodents. Much of the research with food animals is directed toward improving the utilization of carbohydrates, fat, protein, and fiber for production of meat, milk, and eggs. Research with chicks, rodents, and pigs is often experimental or conceptual in nature so that the results go beyond species–specific answers to fundamental questions related to human health.