High-Throughput Sequencings Revealed That Gut Microbiota Dysbiosis is Implicated in Gouty Arthritis of Red-Crowned Crane (Grus japonensis).

The red-crowned crane (Grus japonensis) is one of the rarest cranes with a global population of less than 4000 individuals. The population of red-crowned crane could be influenced by health threats, including metabolic and infectious diseases. In the Wildlife Rescue Center of Suining County of Jiangsu Province, gouty arthritis (GA) was observed in all four red-crowned cranes since March 2024. A pooled fecal supernatant was first submitted to metagenomics sequencing for screening disease-associated pathogens. Enterobacteria phage phiEcoM-GJ1 was detected as the predominant virus while Escherichia coli and Aeromonas hydrophila were the dominated bacteria in the mixed fecal sample from red-crowned cranes. The 16S rRNA gene sequencing was further performed on both the mixed fecal sample and four individual samples, which showed that Escherichia-Shigella, Lactobacillus, and Enterococcus were the most abundant gut flora in both mixed and individual fecal samples. Furthermore, bacteria isolation and identification with matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF/MS) confirmed that Escherichia coli was predominant (19/29 colonies, 65.52%) in the feces. Therefore, anti-uricacid and antibacteria treatments using plantain herb, doxycycline, Vitamin AD3 and multivitamin B were adopted, leading to a full behavioral recovery within 1 month. Overall, this case-based observational study provides first clue on the gut-joint axis in red-crowned cranes, supporting that gut microbiota dysbiosis is closely associated with GA in red-crowned cranes.