We hypothesized that balancing the content of exogenous amino acids, especially lysine, to reduce protein content in swine diets could reduce nitrogen(N) pollution associated with animal husbandry. Two experiments(45 ...We hypothesized that balancing the content of exogenous amino acids, especially lysine, to reduce protein content in swine diets could reduce nitrogen(N) pollution associated with animal husbandry. Two experiments(45 d each experiment) were performed on weaned piglets(Duroc x Landrace x Yorkshire,28 d of age) to test this and to determine the optimal lysine to crude protein(Lys:CP) ratio in diet. In Exp. 1,12 piglets(6 replicates [n = 6]) were fed diets containing different levels of CP(17% and 20%) but the same level of Lys, Increased CP content resulted in significant increases(P < 0.05) of average daily gain(ADG), average daily feed intake(ADFI), and body weight(BW);but did not affect the feed to gain ratio. In Exp. 2,24 piglets(8 replicates [n = 8]) were fed 1 of 3 diets as follows: 1) 20% CP with a regular Lys:CP ratio(6.23%, control);2) 17% CP with a reduced Lys:CP ratio(6.14%, LL);or 3) 17% CP with a standard Lys:CP ratio(7.32%, SL). The ADG, final BW, serum concentrations of growth hormone and insulin-like growth factor-1, villus height in the jejunum, and villus height to crypt depth ratio were the lowest in piglets fed LL diet, whereas blood urea N concentration was the lowest and the value of lipase activity was the highest in the piglets fed SL diet. The SL diet did not affect growth performance,intestinal morphology, or serum hormone concentrations, indicating that reduced dietary N with a high Lys:CP ratio can efficiently reduce dietary N excretion without negatively affecting weaned piglets.展开更多
基金supported by the China Basic Research Program (#2013CB127301)National Natural Science Foundation of China (31472106, 31501964)+5 种基金Natural Science Foundation of Hunan Province of China (2018JJ3579)Ministry of Science and Technology of the People’s Republic of China (2013BAD21B04)Key Programs of frontier scientific research of the Chinese Academy of Sciences (QYZDY-SSW-SMC008)Youth Innovation Team Project of ISA,CAS (2017QNCXTD_TBE)China Agriculture Research System (CARS-35)the Public Service Technology Center,Institute of Subtropical Agriculture, Chinese Academy of Sciences
文摘We hypothesized that balancing the content of exogenous amino acids, especially lysine, to reduce protein content in swine diets could reduce nitrogen(N) pollution associated with animal husbandry. Two experiments(45 d each experiment) were performed on weaned piglets(Duroc x Landrace x Yorkshire,28 d of age) to test this and to determine the optimal lysine to crude protein(Lys:CP) ratio in diet. In Exp. 1,12 piglets(6 replicates [n = 6]) were fed diets containing different levels of CP(17% and 20%) but the same level of Lys, Increased CP content resulted in significant increases(P < 0.05) of average daily gain(ADG), average daily feed intake(ADFI), and body weight(BW);but did not affect the feed to gain ratio. In Exp. 2,24 piglets(8 replicates [n = 8]) were fed 1 of 3 diets as follows: 1) 20% CP with a regular Lys:CP ratio(6.23%, control);2) 17% CP with a reduced Lys:CP ratio(6.14%, LL);or 3) 17% CP with a standard Lys:CP ratio(7.32%, SL). The ADG, final BW, serum concentrations of growth hormone and insulin-like growth factor-1, villus height in the jejunum, and villus height to crypt depth ratio were the lowest in piglets fed LL diet, whereas blood urea N concentration was the lowest and the value of lipase activity was the highest in the piglets fed SL diet. The SL diet did not affect growth performance,intestinal morphology, or serum hormone concentrations, indicating that reduced dietary N with a high Lys:CP ratio can efficiently reduce dietary N excretion without negatively affecting weaned piglets.
