Dai Dong, Gao Libing, Pan Yingli, Chen Chaojiang, Ma Kaixuan, Zhang Haijun, Wu Shugeng, Qi Guanghai, Wang Jing
Key Laboratory of Feed Biotechnology, Ministry of Agriculture and Rural Affairs, Institute of Feed Research, Chinese Academy of Agricultural Sciences, Beijing 100081, PR China.
Beijing Huadu Yukou Poultry Industry Co., Ltd, Beijing 101200, PR China.
Poult Sci. 2025 May 2;104(8):105258. doi: 10.1016/j.psj.2025.105258.
The significant depigmentation of brown eggshells occurs in the in the late-phase laying hens, which directly affects consumer acceptance. However, the biological mechanism of eggshell depigmentation based on uterine metabolism has not been elucidated. In this study, a total of 4 group were as follows: 1) 65-week-old laying hens with normal color; 2) 65-week-old laying hens with light color; 3) 80-week-old laying hens with normal color; 4) 80-week-old laying hens with light color. Variations in the pigment contents, uterine antioxidant capacity, uterine microbiota, and uterine metabolomics were examined in current study. Results showed that significantly decreased L* values and increased a* and b* values were observed in the depigmentation group (P < 0.05). The protoporphyrin IX content of the uterus with eggshell depigmentation was significantly decreased in 65-week-old laying hens (P < 0.05). Uterine MDA content was significantly increased in the depigmentation groups at 65 and 80 weeks of age, accompanied by reduced SOD and increased IgA levels (P > 0.05). The abundance of Proteobacteria and Campilobacterota was markedly reduced in the uterus with eggshell depigmentation, whereas Firmicutes was elevated at 65 weeks of age (P < 0.05). Further, Psychrobacte as biomarkers can accurately distinguish between normal color and depigmentation in eggshells (AUC = 0.91). A total of 51 differential metabolites were significantly enriched in the down-regulated sphingolipid metabolism, linoleic acid metabolism, citrate cycle, oxidative phosphorylation, PPAR signaling pathway, FoxO signaling pathway, and apoptosis at 65 weeks of age (P < 0.05). Meanwhile, there were 82 differential metabolites were significantly up-regulated at 80 weeks of age, which mainly enriched in up-regulated linoleic acid metabolism, purine metabolism, and pentose phosphate pathway (P < 0.05). These findings elucidate the specific metabolic mechanisms responsible for eggshell depigmentation in 65- and 80-week-old laying hens, contributing to the improvement of eggshell depigmentation by the precise nutritional modulation in the late-phase laying hens.
褐壳蛋蛋壳明显褪色现象出现在产蛋后期母鸡中，这直接影响消费者的接受度。然而，基于子宫代谢的蛋壳褪色生物学机制尚未阐明。在本研究中，共分为4组：1）65周龄正常颜色的产蛋母鸡；2）65周龄浅色的产蛋母鸡；3）80周龄正常颜色的产蛋母鸡；4）80周龄浅色的产蛋母鸡。本研究检测了色素含量、子宫抗氧化能力、子宫微生物群和子宫代谢组学的变化。结果显示，在褪色组中观察到显著降低的L值以及升高的a和b*值（P<0.05）。65周龄产蛋母鸡中，蛋壳褪色的子宫中原卟啉IX含量显著降低（P<0.05）。65周龄和80周龄的褪色组子宫MDA含量显著增加，同时SOD降低，IgA水平升高（P>0.05）。蛋壳褪色的子宫中变形菌门和弯曲杆菌门的丰度显著降低，而在65周龄时厚壁菌门升高（P<0.05）。此外，嗜冷杆菌作为生物标志物可以准确区分蛋壳的正常颜色和褪色情况（AUC=0.91）。在65周龄时，共有51种差异代谢物在下调的鞘脂代谢、亚油酸代谢、柠檬酸循环、氧化磷酸化、PPAR信号通路、FoxO信号通路和凋亡中显著富集（P<0.05）。同时，在80周龄时有82种差异代谢物显著上调，主要富集在上调的亚油酸代谢、嘌呤代谢和磷酸戊糖途径中（P<0.05）。这些发现阐明了65周龄和80周龄产蛋母鸡蛋壳褪色的具体代谢机制，有助于通过对产蛋后期母鸡进行精准营养调控来改善蛋壳褪色情况。
