Urea and other nonprotein nitrogen products can be utilized by the microorganisms of the rumen for the production of protein. They are not generally recommended for goats because they are very selective in their diets. All discussions of nutrition seem to begin with energy, probably because this is the best defined requirement of farm animals and is expensive. Most of the goat's energy comes from the breakdown of the fiber of forages, while the remainder comes from the burning up of concentrate starches and fats. Over a longer period of time effects such as retarded growth, delayed puberty, and decreased fertility will become apparent.
Energy is measured in two different ways by the feed industry.
The TDN system takes into consideration only one nutrient loss - feces. For this reason, the net energy system is gaining in popularity. This system considers energy that is lost in the feces, urine, gases, and the work of digestion. In recent years this system has been even more refined to account for varying energy utilization needs for body maintenance, weight gain, or milk production. Minerals Many minerals are required by the goat.