This study aimed to evaluate the blood bacterial microbiota in healthy and febrile cats. High-quality sequencing reads from the 16S rRNA gene variable region V3-V4 were obtained from genomic blood DNA belonging to 145 healthy cats, and 140 febrile cats. Comparisons between the blood microbiota of healthy and febrile cats revealed dominant presence of Actinobacteria, followed by Firmicutes and Proteobacteria, and a lower relative abundance of Bacteroidetes. Upon lower taxonomic levels, the bacterial composition was significantly different between healthy and febrile cats. The families Faecalibacterium and Kineothrix (Firmicutes), and Phyllobacterium (Proteobacteria) experienced increased abundance in febrile samples. Whereas Thioprofundum (Proteobacteria) demonstrated a significant decrease in abundance in febrile. The bacterial composition and beta diversity within febrile cats was different according to the affected body system (Oral/GI, systemic, skin, and respiratory) at both family and genus levels. Sex and age were not significant factors affecting the blood microbiota of febrile cats nor healthy ones. Age was different between young adult and mature adult healthy cats. Alpha diversity was unaffected by any factors. Overall, the findings suggest that age, health status and nature of disease are significant factors affecting blood microbiota diversity and composition in cats, but sex is not.

本研究旨在评估健康猫和发热猫的血液细菌微生物群。从 145 只健康猫和 140 只发热猫的基因组血液 DNA 中获得了 16S rRNA 基因可变区 V3-V4 的高质量测序读数。健康猫和发热猫的血液微生物群之间的比较显示，放线菌占主导地位，其次是厚壁菌门和变形菌门，而拟杆菌门的相对丰度较低。在较低的分类水平上，健康猫和发热猫之间的细菌组成存在显着差异。粪杆菌科、动毛菌属（厚壁菌门）和叶杆菌属（变形菌门）在发热样本中的丰度增加。而 Thioprofundum（变形菌）在发热时丰度显着下降。根据受影响的身体系统（口腔/胃肠道、全身、皮肤和呼吸系统）的不同，发热猫体内的细菌组成和β多样性在科和属水平上都不同。性别和年龄并不是影响发热猫和健康猫血液微生物群的重要因素。年轻成年猫和成年健康猫的年龄不同。 Alpha多样性不受任何因素的影响。总体而言，研究结果表明，年龄、健康状况和疾病性质是影响猫血液微生物群多样性和组成的重要因素，但性别不是。