The gut microbiota influences chicken health, welfare, and productivity. A diverse and balanced microbiota has been associated with improved growth, efficient feed utilisation, a well-developed immune system, disease resistance, and stress tolerance in chickens. Previous studies on chicken gut microbiota have predominantly focused on broiler chickens and have usually been limited to one or two sections of the digestive system, under controlled research environments, and often sampled at a single time point. To extend these studies, this investigation examined the microbiota of commercially raised layer chickens across all major gut sections of the digestive system and with regular sampling from rearing to the end of production at 80 weeks. The aim was to build a detailed picture of microbiota development across the entire digestive system of layer chickens and study spatial and temporal dynamics. The taxonomic composition of gut microbiota differed significantly between birds in the rearing and production stages, indicating a shift after laying onset. Similar microbiota compositions were observed between proventriculus and gizzard, as well as between jejunum and ileum, likely due to their anatomical proximity. Lactobacillus dominated the upper gut in pullets and the lower gut in older birds. The oesophagus had a high proportion of Proteobacteria, including opportunistic pathogens such as Gallibacterium. Relative abundance of Gallibacterium increased after peak production in multiple gut sections. Aeriscardovia was enriched in the late-lay phase compared to younger birds in multiple gut sections. Age influenced microbial richness and diversity in different organs. The upper gut showed decreased diversity over time, possibly influenced by dietary changes, while the lower gut, specifically cecum and colon, displayed increased richness as birds matured. However, age-related changes were inconsistent across all organs, suggesting the influence of organ-specific factors in microbiota maturation. Addressing a gap in previous research, this study explored the microbiota across all major gut sections and tracked their dynamics from rearing to the end of the production cycle in commercially raised layer chickens. This study provides a comprehensive understanding of microbiota structure and development which help to develop targeted strategies to optimise gut health and overall productivity in poultry production.

中文翻译：

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蛋鸡微生物群：对所有主要肠道部分的空间和时间动态的综合分析

肠道微生物群影响鸡的健康、福利和生产力。多样化且平衡的微生物群与鸡的生长改善、饲料高效利用、免疫系统发育良好、抗病性和应激耐受性相关。以前对鸡肠道微生物群的研究主要集中在肉鸡上，通常仅限于消化系统的一两个部分，在受控的研究环境下，并且通常在单个时间点采样。为了扩展这些研究，本研究检查了商业饲养的蛋鸡消化系统所有主要肠道部分的微生物群，并从饲养到生产结束 80 周定期取样。目的是建立蛋鸡整个消化系统微生物群发育的详细图景，并研究空间和时间动态。在饲养和生产阶段，鸟类肠道微生物群的分类组成存在显着差异，表明产蛋开始后发生了变化。在腺胃和肌胃之间以及空肠和回肠之间观察到类似的微生物群组成，这可能是由于它们的解剖学上的接近性。乳酸菌在小母鸡的上肠道和老鸟的下肠道中占主导地位。食道中有很高比例的变形菌，包括机会性病原体，例如鸡杆菌。多个肠道切片中的鸡杆菌的相对丰度在达到峰值后增加。与幼禽相比，在多个肠道切片中，产蛋后期白粉菌含量丰富。年龄影响不同器官中微生物的丰富度和多样性。随着时间的推移，上消化道的多样性逐渐减少，这可能是受到饮食变化的影响，而下消化道，特别是盲肠和结肠，随着鸟类的成熟而显示出丰富度的增加。然而，所有器官中与年龄相关的变化并不一致，这表明器官特异性因素对微生物群成熟的影响。为了解决之前研究中的空白，本研究探索了所有主要肠道部分的微生物群，并跟踪了商业饲养蛋鸡从饲养到生产周期结束的动态。这项研究提供了对微生物群结构和发育的全面了解，有助于制定有针对性的策略，以优化肠道健康和家禽生产的整体生产力。