Yin Jie, Li Yuying, Zhu Xiaotong, Han Hui, Ren Wenkai, Chen Shuai, Bin Peng, Liu Gang, Huang Xingguo, Fang Rejun, Wang Bin, Wang Kai, Sun Liping, Li Tiejun, Yin Yulong
Key Laboratory of Agro-Ecological Processes in Subtropical Region, Institute of Subtropical Agriculture, Chinese Academy of Sciences; National Engineering Laboratory for Pollution Control and Waste Utilization in Livestock and Poultry Production; Hunan Provincial Engineering Research Center for Healthy Livestock and Poultry Production; Scientific Observing and Experimental Station of Animal Nutrition and Feed Science in South-Central, Ministry of Agriculture, Changsha, Hunan 410125, P. R. China.
University of Chinese Academy of Sciences , Beijing 100039, China.
J Agric Food Chem. 2017 Oct 25;65(42):9297-9304. doi: 10.1021/acs.jafc.7b02746. Epub 2017 Oct 11.
This study aimed to investigate the long-term effects of protein restriction from piglets to finishing pigs for 16 weeks on meat quality, muscle amino acids, and amino acid transporters. Thirty-nine piglets were randomly divided into three groups: a control (20-18-16% crude protein, CP) and two protein restricted groups (17-15-13% CP and 14-12-10% CP). The results showed that severe protein restriction (14-12-10% CP) inhibited feed intake and body weight, while moderate protein restriction (17-15-13% CP) had little effect on growth performance in pigs. Meat quality (i.e., pH, color traits, marbling, water-holding capacity, and shearing force) were tested, and the results exhibited that 14-12-10% CP treatment markedly improved muscle marbling score and increased yellowness (b*). pH value (45 min) was significantly higher in 17-15-13% CP group than that in other groups. In addition, protein restriction reduced muscle histone, arginine, valine, and isoleucine abundances and enhanced glycine and lysine concentrations compared with the control group, while the RT-PCR results showed that protein restriction downregulated amino acids transporters. Mechanistic target of rapamycin (mTOR) signaling pathway was inactivated in the moderate protein restricted group (17-15-13% CP), while severe protein restriction with dietary 14-12-10% CP markedly enhanced mTOR phosphorylation. In conclusion, long-term protein restriction affected meat quality and muscle amino acid metabolism in pigs, which might be associated with mTOR signaling pathway.
本研究旨在调查从仔猪到育肥猪16周的蛋白质限制对肉质、肌肉氨基酸和氨基酸转运体的长期影响。39头仔猪被随机分为三组：对照组（粗蛋白20 - 18 - 16%，CP）和两个蛋白质限制组（17 - 15 - 13% CP和14 - 12 - 10% CP）。结果表明，严重蛋白质限制（14 - 12 - 10% CP）抑制采食量和体重，而适度蛋白质限制（17 - 15 - 13% CP）对猪的生长性能影响不大。对肉质（即pH值、颜色特征、大理石纹、持水力和剪切力）进行了测试，结果显示14 - 12 - 10% CP处理显著提高了肌肉大理石纹评分并增加了黄度（b*）。17 - 15 - 13% CP组的pH值（45分钟）显著高于其他组。此外，与对照组相比，蛋白质限制降低了肌肉组蛋白、精氨酸、缬氨酸和异亮氨酸的丰度，提高了甘氨酸和赖氨酸的浓度，而RT-PCR结果表明蛋白质限制下调了氨基酸转运体。适度蛋白质限制组（17 - 15 - 13% CP）中雷帕霉素靶蛋白（mTOR）信号通路失活，而日粮14 - 12 - 10% CP的严重蛋白质限制显著增强了mTOR磷酸化。总之，长期蛋白质限制影响猪的肉质和肌肉氨基酸代谢，这可能与mTOR信号通路有关。
