College of Animal Science and Technology, Southwest University, Beibei, 400715 Chongqing, P. R. China.
State Key Laboratory of Swine and Poultry Industry, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, Sichuan Province, P. R. China.
Poult Sci. 2024 Sep;103(9):103994. doi: 10.1016/j.psj.2024.103994. Epub 2024 Jun 24.
Different rearing systems have varying effect on animal welfare and meat quality of poultry. Currently, there are no established standards for the rearing systems of Chinese indigenous chickens. Our study aimed to investigate the effects of different rearing systems on the meat quality, gene profiles, and metabolites of Chinese indigenous chickens (Nanchuan chicken). 10-wk-old Nanchuan chickens (n=360) were randomly divided into 3 groups (cage, net, and free-range groups), with 6 replicates per group (20 chickens per replicate). The experiment lasted for 12 wk. At 154-days-old, 36 healthy chickens (6 males and 6 females per group) were randomly selected, euthanized, and their breast muscles were collected to assess the meat quality parameters and histomorphological characteristics. Additionally, breast muscles from 18 random hens (3 males and 3 females per group) were used for metabolomics and RNA-seq analysis. The results showed that rearing systems significantly affected the meat quality and myofiber characteristics. The meat quality of breast muscles from free-range chickens was superior to that of caged chickens, characterized by more tender meat and smaller myofiber cross-sectional areas. Integrative metabolomics and transcriptomics analysis revealed that the differentially expressed genes of chicken breast muscles were primarily involved in the myofiber differentiation. Mechanically, the improved meat quality of breast muscle in free-range chickens were mainly associated with enhanced skeletal muscle differentiation facilitated by fibromodulin, increased levels of up-regulated Acetyl-L-carnitine and Propionylcarnitine level, and decreased levels of Nonanoic acid and Elaidic acid abundance (Graphical abstract). This provides a comprehensive understanding of the most effective and sustainable breeding, production, and rearing systems for Chinese indigenous chickens. It also contributes to the current knowledge of the molecular mechanisms underlying the effects of rearing systems on growth performance and meat quality of chickens.
不同的饲养系统对家禽的动物福利和肉质有不同的影响。目前，中国本土鸡的饲养系统还没有建立标准。我们的研究旨在探讨不同饲养系统对中国本土鸡（南川鸡）肉质、基因谱和代谢物的影响。将 10 周龄的南川鸡（n=360）随机分为 3 组（笼养、网养和散养组），每组 6 个重复（每个重复 20 只鸡）。实验持续 12 周。在 154 日龄时，随机选择 36 只健康鸡（每组 6 只公鸡和 6 只母鸡），安乐死并采集胸肌，以评估肉质参数和组织形态学特征。此外，还从 18 只随机母鸡（每组 3 只公鸡和 3 只母鸡）的胸肌中提取代谢组学和 RNA-seq 分析。结果表明，饲养系统显著影响肉质和肌纤维特征。散养鸡的胸肌肉质优于笼养鸡，肉质更嫩，肌纤维横截面积更小。综合代谢组学和转录组学分析表明，鸡胸肌差异表达基因主要参与肌纤维分化。在机制上，散养鸡胸肌肉质的改善主要与纤维调节素促进的骨骼肌分化增强有关，上调的乙酰肉碱和丙酰肉碱水平升高，壬酸和反油酸丰度降低有关（示意图）。这为中国本土鸡最有效和可持续的养殖、生产和饲养系统提供了全面的了解。它还为饲养系统对鸡生长性能和肉质影响的分子机制提供了当前的知识。
