Feng Xin, Hua Rong, Zhang Wanying, Liu Yuhang, Luo Caiyu, Li Tonghao, Chen Xiaolin, Zhu Hui, Wang Youcong, Lu Yan
School of Life Science and Engineering, Foshan University, Foshan, China.
Beijing Key Laboratory of Captive Wildlife Technologies, Beijing Zoo, Beijing, China.
Front Vet Sci. 2023 Feb 16;10:986382. doi: 10.3389/fvets.2023.986382. eCollection 2023.
Elephants are endangered species and threatened with extinction. They are monogastric herbivorous, hindgut fermenters and their digestive strategy requires them to consume large amounts of low quality forage. The gut microbiome is important to their metabolism, immune regulation, and ecological adaptation. Our study investigated the structure and function of the gut microbiota as well as the antibiotic resistance genes (ARGs) in captive African and Asian elephants on the same diet. Results showed that captive African and Asian elephants had distinct gut bacterial composition. MetaStats analysis showed that the relative abundance of ( = 0.00) and ( = 0.01) at the phylum level as well as ( = 0.01) and ( = 0.02) at the family level varied between captive African and Asian elephants. Among the top ten functional subcategories at level 2 (57 seed pathway) of Kyoto Encyclopedia of Genes and Genomes (KEGG) database, the relative gene abundance of cellular community-prokaryotes, membrane transport, and carbohydrate metabolism in African elephants were significantly lower than those in Asian elephants (0.98 vs. 1.03%, = 0.04; 1.25 vs. 1.43%, = 0.03; 3.39 vs. 3.63%; = 0.02). Among the top ten functional subcategories at level 2 (CAZy family) of CAZy database, MetaStats analysis showed that African elephants had higher relative gene abundance of Glycoside Hydrolases family 28 (GH 28) compared to Asian elephants (0.10 vs. 0.08%, = 0.03). Regarding the antibiotic resistance genes carried by gut microbes, MetaStats analysis showed that African elephants had significantly higher relative abundance of ( = 0.00), ( = 0.04), and ( = 0.04) than Asian elephants encoding resistance for glycopeptide, tetracycline, and macrolide/rifamycin/fluoroquinolone antibiotic, respectively. In conclusion, captive African and Asian elephants on the same diet have distinct gut microbial communities. Our findings established the ground work for future research on improving gut health of captive elephants.
大象是濒危物种，面临灭绝威胁。它们是单胃草食性动物，属于后肠发酵者，其消化策略要求它们消耗大量低质量草料。肠道微生物群对它们的新陈代谢、免疫调节和生态适应很重要。我们的研究调查了圈养的非洲象和亚洲象在相同饮食条件下肠道微生物群的结构和功能以及抗生素抗性基因（ARGs）。结果表明，圈养的非洲象和亚洲象有不同的肠道细菌组成。MetaStats分析表明，在门水平上，非洲象和亚洲象的 （ = 0.00）和 （ = 0.01）的相对丰度以及在科水平上 （ = 0.01）和 （ = 0.02）的相对丰度有所不同。在京都基因与基因组百科全书（KEGG）数据库二级（57个种子途径）的十大功能子类别中，非洲象的细胞群落 - 原核生物、膜运输和碳水化合物代谢的相对基因丰度显著低于亚洲象（0.98% 对 1.03%， = 0.04；1.25% 对 1.43%， = 0.03；3.39% 对 3.63%； = 0.02）。在碳水化合物活性酶（CAZy）数据库二级（CAZy家族）的十大功能子类别中，MetaStats分析表明，与亚洲象相比，非洲象的糖苷水解酶家族28（GH 28）的相对基因丰度更高（0.10% 对 0.08%， = 0.03）。关于肠道微生物携带的抗生素抗性基因，MetaStats分析表明非洲象编码对糖肽、四环素和大环内酯/利福霉素/氟喹诺酮抗生素抗性的 （ = 0.00）、 （ = 0.04）和 （ = 0.04）的相对丰度分别显著高于亚洲象。总之，相同饮食条件下的圈养非洲象和亚洲象有不同的肠道微生物群落。我们的研究结果为未来改善圈养大象肠道健康的研究奠定了基础。
