Nutrition is the main factor that affects on animal health and protects animals against some diseases. However, feed additives of probiotics and minerals are the main components that affect animal health. Supplementations of lactic acid bacteria in animal diets can promote intestinal health at weaning as a result of regulating the gut microflora and intestinal absorption, and reduce the frequency of diarrhea post-weaning. Trace minerals are an essential in animal nutrition; and there are narrow ranges between the required and toxic levels in diets. Moreover, use of growth promoter in animal feeding with pharmacological activity on the metabolic and endocrine systems resulting in accelerated weight gain and feed conversion. It could be concluded that from this book, a very strong relationship between nutrition and diseases. Not only nutrients deficiencies are the problem; but also, excess or unbalanced nutrition may cause many of nutritional diseases. Animal producers should try to get a strong background about animal nutrition before they start their project to get the best animal performance and decrease the risk of exposure to nutritional diseases.