【摘要】 山西某羊驼养殖场内出现母羊驼流产、产弱胎，羔羊驼出生后不久死亡的情况。研究旨在确定引起羊驼发病的病原，并为养殖场提供诊断和疾病防控的思路，无菌采集病死羊驼的心脏、肝脏、脾脏和肾脏，取病料接种于多种培养基进行培养，观察其生长情况，并取单菌落涂片染色观察菌体形态；采用PCR方法对分离株进行鉴定，并进行药敏试验。结果显示，多种培养基上均有菌落生长，在鉴别培养基麦康凯和SS琼脂上生长出粉红色的菌落，伊红亚甲蓝琼脂上生长出有金属光泽的小菌落；显微镜下观察可见大量染成红色的细小杆菌，菌体单一均匀；上述菌落、菌体形态特征均与弗格森埃希菌一致。通过PCR扩增、测序和序列比对后，确定分离株为弗格森埃希菌。药敏试验结果显示，分离株对喹诺酮类、氨基糖苷类、头孢菌素类药物以及阿奇霉素、氟苯尼考均表现敏感。研究表明，引起养殖场内羊驼发病的病原鉴定为弗格森埃希菌，其对喹诺酮类药物、氨基糖苷类药物、头孢菌素类药物以及阿奇霉素、氟苯尼考敏感。更多还原

【Abstract】 A case of abortions, weak births, and neonatal mortality in alpacas occurred on a farm in Shanxi Province. This study aimed to identify the causative pathogen and provide diagnostic and disease control strategies for the farm. Heart, liver, spleen, and kidney samples from deceased alpacas were aseptically collected and inoculated onto multiple culture media, for bacterial isolation. Colony growth was observed, and single colonies were subjected to Gram staining for morphological analysis. The isolates were further identified by PCR and antimicrobial susceptibility testing. Results showed bacterial growth on all media. Colonies appeared pink on MacConkey and SS agar, while small colonies with metallic sheen were observed on eosin methylene blue(EMB) agar. Microscopic examination revealed abundant uniform Gramnegative bacilli. These morphological characteristics aligned with Escherichia fergusonii. PCR amplification, sequencing, and BLAST analysis confirmed the isolates as Escherichia fergusonii. Antimicrobial susceptibility testing indicated that the isolates were susceptible to fluoroquinolones, aminoglycosides, cephalosporins, azithromycin, and florfenicol. The study identified Escherichia fergusonii as the causative pathogen responsible for the alpaca infections on this farm, demonstrating susceptibility to fluoroquinolones, aminoglycosides, cephalosporins, azithromycin, and florfenicol.更多还原