Introduction: "innovation, change, breaking the situation", entering a new era, in order to further deepen the "three aspects", promote the academic exchange of animal nutrition, and help the growth of young talents, "summer peace Youth Award" came into being, young scholars from 27 member units under the Key Laboratory of animal nutrition and feed subject group of the Ministry of agriculture and rural areas will present their recent years to the industry one by one Major research results. Their efforts, efforts and gains will be the perfect interpretation of the continuous development and innovation of animal nutrition people in the new era!
Dr. Xing Tong
Key Laboratory of animal physiology and biochemistry, Ministry of agriculture and rural areas
Recommend young scholars
Postdoctoral teacher of School of animal science and technology, Nanjing Agricultural University. Member of the team of the national broiler industry technology system processing laboratory, member of the nutrition regulation team of the broiler industry technology system of Jiangsu Province. He obtained his bachelor's degree from Yangzhou University in 2008-2012, his doctor's degree in food science from Nanjing Agricultural University in 2012-2018, and his doctor's degree was jointly cultivated by Washington State University in 2016-2017.
Mainly engaged in animal nutrition and animal product quality, meat processing and quality control research. He presided over 4 national and provincial level projects, including China's doctoral program, special support program, Jiangsu provincial natural fund youth program, postdoctoral research support program, and participated in 5 national key R & D programs, agricultural industrial technology system, and Jiangsu provincial scientific and technological achievements transformation projects. He has published more than 40 papers, including more than 30 SCI papers and applied for 3 invention patents. At present, he is also a member of China animal products processing research association, China animal husbandry and Veterinary Association, and reviewer of more than ten journals at home and abroad.
Summary of achievements
In the past five years, the research mainly focused on chicken quality control and regulation technology, and the main research results are as follows:
1. It was found that the key links of pre slaughter management and slaughtering process would cause strong stress response to broilers, cause a variety of physiological and biochemical characteristics and metabolic response changes, affect the conversion process of post slaughter muscles to edible meat, and ultimately lead to the decline of chicken quality;
2. To elucidate the mechanism of acute stress induced PSE like chicken by accelerating glycolysis metabolism, mainly by activating AMPK signal pathway in chicken muscle, increasing the activity of hexokinase and pyruvate kinase, accelerating glycolysis metabolism at the early stage of post-mortem, leading to the rapid decline of post-mortem pH, causing egg white degeneration, and finally PSE like meat;
3. It is revealed that acute stress before slaughter can affect the expression of key factors of calcium signal regulation pathway by destroying redox balance, which can cause calcium ion disorder in muscle, and then lead to muscle cell membrane damage, mitochondrial dysfunction, oxidative damage, apoptosis and protein degradation, etc., resulting in the decline of chicken meat quality, which provides a new theoretical basis for explaining the formation mechanism of chicken quality;
4. It was found that the molecular chaperone protein (HSP70) was an important biomarker protein for the formation of chicken quality differences. By constructing the in vitro model of HSP70 differential expression in chicken skeletal muscle cells, the physiological characteristics and metabolic effects of HSP70 targeting calcium homeostasis regulation were revealed, and HSP70 in chicken muscle was constructed by intraperitoneal injection of glutamine The in vivo model of overexpression was used to explain the mechanism of improving chicken quality under acute stress;
5. The nutritional control measures of feeding taurine, guanidine acetic acid and carnosine to relieve stress response and improve meat quality were established.
Representative papers of achievements
Representative paper 1: prototype analysis using isobaric tags for relative and absolute analysis quantification (iTRAQ) revels alternations in stress induced dysfunctional chicken muscle
Abstract: in this study, iTRAQ quantitative proteomics was used to analyze the changes of protein expression profile in PSE like chicken induced by heat transport stress before slaughter. Experimental design: broilers were randomly divided into two groups: control group and 0.5h pre slaughter high temperature transport group (ambient temperature 33 ℃), and pectoralis major muscle was collected. According to the meat quality index, broilers were divided into normal meat and PSE like meat. The activity of plasma stress-related enzymes, muscle microstructure and proteomics were measured respectively. The results showed that the activity of creatine kinase and lactate dehydrogenase in plasma was the highest in PSE like meat group, and the microstructure of muscle showed loose network structure and intercellular space. Proteomic analysis showed that the differential proteins between normal meat and PSE like meat were mainly related to protein conversion, signal transduction, stress and defense, calcium regulation, cell structure and metabolism. The significant differences of glycolysis pathway, calcium signal and chaperone related protein may be the important reasons for the decline of meat quality after slaughter. Proteomic study provides a theoretical basis for further revealing the formation mechanism of stress affecting meat quality traits.
Representative paper 2: di? Erent aerobic status and expression of computational channel components in stress induced dysfunctional chicken muscle
Abstract: the purpose of this study was to investigate the effects of high temperature transport before slaughter on the oxidative status of broiler muscles and the basic elements responsible for Ca2 + transport, sarcoplasmic reticulum calcium pump (serca1) and RyR. Experimental design: broilers were randomly divided into two groups: control group and 0.5h pre slaughter high temperature transport group (ambient temperature 33 ℃), and pectoralis major muscle was collected, and divided into normal meat and PSE like meat according to meat quality indicators. The results showed that high temperature transport could increase the content of plasma corticosterone and the degree of lipid and protein oxidation of pectoralis major muscle. The degree of lipid peroxidation and protein oxidation of PSE meat in transport group was higher than that of normal meat. Compared with the control group, serca1 and α RyR protein and transcription levels in the normal meat of the transport group were significantly higher, while PSE like meat was significantly lower. The results showed that high temperature transport could cause the difference of muscle redox state and SERCA and RyR, which were the important reasons of PSE like meat.
Representative paper 3: stress effects on meat quality: a mechanical perspective
Abstract: in modern animal husbandry, the process of livestock from farm to slaughterhouse inevitably causes stress. The effects of stress on animal behavior, physiological state and meat quality have been widely studied. However, there is a lack of research on the mechanism of stress on the physiological and metabolic changes of livestock and poultry and the mechanism of these physiological and biochemical changes on the formation of meat quality traits. In addition, the specific reasons for the differences in meat quality of different breeds of livestock and poultry, different types of muscle fibers, and even different positions of the same muscle after stress stimulation are not clear. This paper reviews the main stressors, including heat stress, pre slaughter stress, oxidative stress and other stressors that affect animal welfare, carcass quality and food quality, and further describes the potential changes of stress-induced signaling pathways or regulatory factors, including adenylate activated protein kinase mediated energy metabolism, calcium signaling pathway and reactive oxygen free radical crosstalk , protein modification, apoptosis, calpain and cathepsin systems, and heat shock proteins, these changes will cause biochemical changes in the early post-mortem period, and ultimately affect the formation of meat quality traits. Therefore, in order to obtain high-quality livestock meat, we need to reveal the internal mechanism of the changes of these signaling pathways or regulatory factors and the relationship between them.
Dr. Cao Zhijun, Professor of China Agricultural University
Recommended young scholars of "Yihe" Youth Award 2020 Dr. Wang WENCE, associate professor of South China Agricultural University, recommended young scholars of "Yihe" Youth Award 2020 Dr. Chu Beibei, Professor of Henan Agricultural University
Dr. Wang Min, researcher of subtropical Research Institute of Chinese Academy of Sciences, and Dr. Yu Qinghua, Professor of Nanjing Agricultural University
Recommended young scholars of "Yihe" Youth Award 2020 Dr. Che Lianqiang, Professor of Sichuan Agricultural University, recommended young scholars of "Yihe" Youth Award 2020 Dr. Chen Liang, Beijing Institute of animal husbandry and veterinary medicine, Chinese Academy of Sciences
Dr. Wang Xinxia, associate professor, School of animal science, Zhejiang University
Dr. Jiang Weidan, Professor of Sichuan Agricultural University
Dr. Cheng Yanfen, Professor of Nanjing Agricultural University
Dr. Wang Songbo, Professor of South China Agricultural University
Dr. Zhou Zhenming, associate professor, School of animal science and technology, China Agricultural University
Dr. he Pingli, associate researcher of School of animal science and technology of China Agricultural University
Dr. Wang Xiumin, deputy researcher of feed Research Institute, Chinese Academy of Agricultural Sciences
Dr. Wang Jianping, associate professor of Sichuan Agricultural University
Dr. Zhang Jize, assistant researcher of Grassland Research Institute, Chinese Academy of Agricultural Sciences