背景:候鸟在越冬期间在觅食策略方面表现出异质性,以应对环境和迁徙压力,和肠道细菌响应宿主饮食的变化。然而,关于黑颈鹤(Grusnigricollis)越冬期间饮食和肠道真菌的动态知之甚少。
结果:在这项工作中,我们对trnL-P6环和ITS1区域进行了扩增子测序,以表征越冬期间黑颈鹤的饮食组成和肠道真菌组成。结果表明,在越冬期间,黑颈鹤的植物性饮食主要由禾本科,茄科,和Polysho科。其中,茄科的丰富,虎杖科,豆科,石竹科在越冬后期明显较高,这也导致在此期间黑颈鹤更均匀地消耗各种食物。越冬期肠道真菌群落多样性和核心真菌丰度较为保守,主要以子囊菌和担子菌为主。LEfSe分析(P<0.05,LDA>2)发现,Pseudopeziza,孢子虫,Geotrichum,乳头状瘤在初冬明显丰富,在冬季中期,ramularia和Dendryphion明显富集,Barnettozyma在冬末明显丰富,在冬末,胸曲明显丰富。最后,mantel测试表明冬季饮食与肠道真菌之间存在显着相关性。
结论:本研究揭示了黑颈鹤在大山堡越冬期间食物成分和肠道真菌群落的动态变化。在越冬后期,他们对环境和迁徙压力的反应是扩大饮食,增加非首选食物的摄入量,促进各种食物的消费比例更加平衡。平衡的食物组成在稳定肠道真菌群落结构方面发挥了重要作用。而肠道真菌有效提高了宿主的食物利用率,他们还可能面临引入病原真菌的潜在风险。此外,我们认识到粪便试验在研究动物肠道真菌组成方面的局限性,因为它不能有效区分来自食物或土壤的真菌类群和肠道。未来对培养和宏基因组学等功能的研究可能会进一步阐明真菌在肠道生态系统中的作用。
BACKGROUND: Migratory birds exhibit heterogeneity in foraging strategies during wintering to cope with environmental and migratory pressures, and gut bacteria respond to changes in host diet. However, less is known about the dynamics of diet and gut fungi during the wintering period in black-necked cranes (Grus nigricollis).
RESULTS: In this work, we performed amplicon sequencing of the trnL-P6 loop and ITS1 regions to characterize the dietary composition and gut fungal composition of black-necked cranes during wintering. Results indicated that during the wintering period, the plant-based diet of black-necked cranes mainly consisted of families Poaceae, Solanaceae, and Polygonaceae. Among them, the abundance of Solanaceae, Polygonaceae, Fabaceae, and Caryophyllaceae was significantly higher in the late wintering period, which also led to a more even consumption of various food types by black-necked cranes during this period. The diversity of gut fungal communities and the abundance of core fungi were more conserved during the wintering period, primarily dominated by Ascomycota and Basidiomycota. LEfSe analysis (P < 0.05, LDA > 2) found that Pyxidiophora, Pseudopeziza, Sporormiella, Geotrichum, and Papiliotrema were significantly enriched in early winter, Ramularia and Dendryphion were significantly enriched in mid-winter, Barnettozyma was significantly abundant in late winter, and Pleuroascus was significantly abundant in late winter. Finally, mantel test revealed a significant correlation between winter diet and gut fungal.
CONCLUSIONS: This study revealed the dynamic changes in the food composition and gut fungal community of black-necked cranes during wintering in Dashanbao. In the late wintering period, their response to environmental and migratory pressures was to broaden their diet, increase the intake of non-preferred foods, and promote a more balanced consumption ratio of various foods. Balanced food composition played an important role in stabilizing the structure of the gut fungal community. While gut fungal effectively enhanced the host\'s food utilization rate, they may also faced potential risks of introducing pathogenic fungi. Additionally, we recongnized the limitations of fecal testing in studying the composition of animal gut fungal, as it cannot effectively distinguished between fungal taxa from food or soil inadvertently ingested and intestines. Future research on functions such as cultivation and metagenomics may further elucidate the role of fungi in the gut ecosystem.