A REVIEW OF LINEAR RELATOINSHIPS BETWEEN ENERGY AND PROTEIN IN RUMINANT ANIMAL NUTRITION

Abstract

The production of high quality protein such as meat, milk and eggs for human consumption and by-products such as hides and skin, wool, fur, hoofs, horns and manure requires large quantities of protein and energy , thus a good understanding of the linear relationships between protein and energy is important for improving efficiency and productivity in ruminant animal production.. Consequently energy and protein requirements , various linear relationships or interactions between protein and energy , mechanisms for energy supply for microbial protein synthesis as well as appropriate combinations of protein and energy feeds in ruminant animal nutrition as elucidated by various researchers were collated and discussed. Protein requirements depends on body weight and rate of gain, as a general rule, the protein requirement for maintenance is relatively low but the requirement for gain is relatively high the opposite is true for energy- requirement is high for maintenance the metabolizable energy requirement for 0.75 calves for maintenance has been estimated as 115 kcal/kg . Energy required for gain of 0335 1.2 veal was described by the following equation ME=0.lLw 0.75x0.84 (LW ) (LW ) where ME is the metabolizable energy requirement in kcal, LW is the live weight in Kg and LWG is she live weight gain in kg. The most important purpose to which feed nutrients are put is the production of energy, therefore feed intake is almost synonymous with energy intake. The concept of total digestible nutrient which is the sum of all digestible organic nutrients, carbohydrates, protein and fats (2.25) represents the approximate energy value of feeds these nutrients may be immediately used for energy or stored as glycogen, fat or gets incorporated into the body tissue. When ever there is shortage, energy stored in form of glycogen or fat will be mobilized and when these sources are exhausted, proteins will be hydrolyzed and delaminated and used for energy production. Thus every organic nutrient, except vitamins, is a source of energy . It was concluded that better knowledge of the energy and protein requirements, the linear relationships that exists between protein and energy as well as how to combine protein and energy feeds in ruminant animal nutrition was very important for efficient and productive ruminant animal production. Further research on the protein and energy requirements and the linear relationships that exists between protein and energy was recommended.