Optimization of protein quality and level in pigs’ diets to reduce nitrogen excretion in pork production

Abstract

Livestock is a significant source of reactive nitrogen in the environment. It is estimated that of the total amount of NH3 and N2O released into the environment as a result of human activities, about 70 % and 30 %, respectively, are formed in the livestock industry. Reducing the protein content of the diet is an effective way to reduce the excretion of N in pig urine. This can be done by improving the amino acid balance, which leads to a reduction in excess protein in the diet. Without the right combination of amino acids in the diet is inconceivable efficient and cost-effective production of livestock products. Two physiological balance experiments were conducted on the basis of the physiological yard of the Institute of Pig Breeding and APV NAAS to optimize nitrogen emissions of pigs into the environment. The first study on the optimization of nitrogen emissions by pigs under the conditions of combined use of plant and animal resources of feed protein for this purpose was formed 2 research groups of 8 heads each. The first group received a normal diet, the second received feed using plant and animal sources of feed protein. The second investigated the optimization of nitrogen emissions by pigs under conditions of reduced protein levels in diets using balancing amino acids and multienzyme compositions. To conduct a physiological balance experiment, three groups of pigs of 6 heads each were formed. The first group received a standard diet, the second with a reduced protein content and the addition of balancing amino acids, the third the second with a reduced protein content and the addition of balancing amino acids and multi-enzyme complex. It was found that the use of experimental diets with low fiber and anti-nutritional factors that use combined sources of protein nitrogen excretion in animals is likely to decrease, and the efficiency of nitrogen use increases by 3.12 % (p≤0.05) and 2.88 % (p≤0.05) from digested. Nitrogen uptake rates by animals receiving feeds with low dietary protein content but with the addition of balancing amino acids and multi-enzyme complex were at the level of animals in the control group. Nitrogen was released using a low-protein diet with the addition of balancing amino acids and (or) multi-enzyme complex, and the environment was lower by 8.71 % in the first and 11.23 % in the second experimental group. Key words: pigs, nitrogen, excretion, protein, amino acids, digestibility, multienzyme composition, low-protein diet, balancing