{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,6]],"date-time":"2026-07-06T10:14:16Z","timestamp":1783332856383,"version":"3.54.6"},"reference-count":48,"publisher":"MDPI AG","issue":"13","license":[{"start":{"date-parts":[[2026,7,4]],"date-time":"2026-07-04T00:00:00Z","timestamp":1783123200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Research and Demonstration on the Innovation of the Black-Spotted Frog Breeding Model","award":["25210010"],"award-info":[{"award-number":["25210010"]}]},{"name":"Hunan Provincial Education Department Outstanding Youth Project","award":["24B0625"],"award-info":[{"award-number":["24B0625"]}]},{"DOI":"10.13039\/501100004735","name":"Natural Science Foundation of Hunan Province","doi-asserted-by":"publisher","award":["2026JJ60022"],"award-info":[{"award-number":["2026JJ60022"]}],"id":[{"id":"10.13039\/501100004735","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Animals"],"abstract":"<jats:p>Amphibian malformation syndromes significantly impact both conservation efforts and aquaculture, yet their underlying systemic pathophysiological mechanisms remain poorly characterized. This study comprehensively examines the multi-level pathological processes associated with the \u201cshort-leg\u201d malformation syndrome in the black-spotted frog (Pelophylax nigromaculatus) using an integrated methodology, encompassing morphological, histopathological, gut microbiome, and hepatic transcriptomic analyses. Affected frogs demonstrated shortened limbs, impaired motor function, and a distinctive metabolic phenotype, including increased body weight despite a shorter body length, accumulation of visceral fat, and shortened intestines. Gut microbiota analysis identified significant compositional shifts, characterized by a decreased Firmicutes-to-Bacteroidota ratio, expansion of pro-inflammatory Proteobacteria, and reduction in beneficial Actinobacteriota, suggesting microbial niche restructuring that likely promotes metabolic and inflammatory disorders. Hepatic transcriptome profiling revealed 2617 differentially expressed genes, demonstrating a clear molecular dichotomy with concurrent up-regulation of immune-related pathways (e.g., neutrophil extracellular trap formation, complement cascades, and inflammatory signaling) and broad suppression of metabolic pathways (e.g., lipid oxidation, nutrient absorption, and PPAR and renin\u2013angiotensin systems). This integrated analysis illustrates that the malformation syndrome represents a systemic pathophysiological state involving dysfunction of the gut\u2013liver axis, characterized by the coexistence of gut microbiota alterations, hepatic metabolic suppression, and immune activation. These findings provide a framework for understanding amphibian malformations and suggest potential strategies to improve health outcomes in aquaculture.<\/jats:p>","DOI":"10.3390\/ani16132069","type":"journal-article","created":{"date-parts":[[2026,7,6]],"date-time":"2026-07-06T08:05:38Z","timestamp":1783325138000},"page":"2069","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Multi-Omics Reveals Gut Microbiota Shifts and Hepatic Metabolic\u2013Immune Alterations in \u201cShort-Leg\u201d Malformed Frog (Pelophylax nigromaculatus)"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-7160-4173","authenticated-orcid":false,"given":"Dan","family":"Zeng","sequence":"first","affiliation":[{"name":"College of Life and Environmental Sciences, Hunan University of Arts and Science, Changde 415000, China"},{"name":"Fisheries College, Hunan Agricultural University, Changsha 410128, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Qin","family":"Qin","sequence":"additional","affiliation":[{"name":"Fisheries College, Hunan Agricultural University, Changsha 410128, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ming","family":"Yang","sequence":"additional","affiliation":[{"name":"Jiangsu Coast Development Group Co., Ltd., Nanjing 210000, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zi\u2019ao","family":"Wang","sequence":"additional","affiliation":[{"name":"College of Animal Science and Technology, Hunan Biological and Electromechanical Polytechnic, Changsha 410127, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jianguo","family":"Xiang","sequence":"additional","affiliation":[{"name":"Fisheries College, Hunan Agricultural University, Changsha 410128, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xiaoqing","family":"Wang","sequence":"additional","affiliation":[{"name":"Fisheries College, Hunan Agricultural University, Changsha 410128, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8382-4608","authenticated-orcid":false,"given":"Yazhou","family":"Hu","sequence":"additional","affiliation":[{"name":"Fisheries College, Hunan Agricultural University, Changsha 410128, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,7,4]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"339","DOI":"10.1111\/jse.12156","article-title":"Black-spotted pond frog (Pelophylax nigromaculatus) on the Chinese Loess Plateau represents a cryptic species: Evidence from molecular phylogeny and ecological niche modeling","volume":"53","author":"Ma","year":"2015","journal-title":"J. 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