国内猪源睾丸酮丛毛单胞菌的分离与鉴定

为查明2018年8月云南省曲靖市富源县某规模化猪场发生母猪产死胎、弱仔猪的病因,本试验采集弱仔猪内脏组织病料进行病原菌的分离培养、生化鉴定、16S rRNA扩增、药敏试验及致病性试验。结果显示,从弱仔猪大脑组织内分离培养出1株菌落形态呈圆形、半透明的革兰氏阴性短杆菌。生化鉴定结果显示,衣康酸盐同化（ITA）、辛二酸盐同化（SUB）、乙酸盐（ACE）、DL-乳酸盐同化（LAT）、丙酸盐同化（PROP）、3-羟基-丁酸盐（3OB）、脯氨酸（PRO）生化反应结果呈阳性;丙氨酸同化（ALA）、D-甘露醇（MAN）、D-葡萄糖（GLU）、癸酸盐（CAP）、丝氨酸同化（SER）等生化反应结果呈阴性,其16S rRNA序列与GenBank中丛毛单胞菌属（Comamonas sp.）EB172株（登录号：EU847238.1）的16S rRNA核苷酸序列同源性达99%。药敏试验结果显示,其对阿莫西林/克拉维酸、头孢噻吩、多黏菌素E、复方新诺明、大观霉素、呋喃妥因和多西环素敏感。致病性试验结果显示,以0.3 mL 9.3×10⁸ CFU/mL的细菌悬液腹腔接种小鼠,72 h内共有7只死亡（7/12）。本试验结果表明,弱仔猪及流产胎儿存在睾丸酮丛毛单胞菌感染。

Isolation and Identification of Comamonas testosteroni from Porcine in China

In order to ascertain the cause of the stillbirth and weak piglets of sows in a large-scale pig farm in Fuyuan county, Qujing city, Yunnan province in August 2018, in this experiment, weak piglets visceral tissue materials were collected for isolation, culture, biochemical identification, 16S rRNA amplification, drug sensitivity test and pathogenicity test.The results showed that a small, translucent Gram-negative brevibacterium was isolated and cultured from weak piglets brain tissue.Biochemical identification results showed that itaconate assimilation (ITA), suberic acid salt assimilation (SUB), acetate (ACE), DL-lactate assimilation (LAT), propionate assimilation (PROP), 3-Hydroxy-butyrate (3OB), proline (PRO) biochemical reaction results were positive;Alanine assimilation (ALA), D-mannitol (MAN), D-glucose (GLU), citrate (CAP), serine assimilation (SER) and other biochemical reactions were negative.The 16S rRNA sequence had 99% homology with the 16S rRNA nucleotide sequence of Comamonas sp.EB172 strain (accession No.:EU847238.1) in GenBank.The susceptibility test showed that it was sensitive to amoxicillin/clavulanic acid, cefotaxime, polymyxin E, cotrimoxazole, spectinomycin, nitrofurantoin and doxycycline.The pathogenicity test showed that mice were inoculated intraperitoneally with 0.3 mL of 9.3×10⁸ CFU/mL bacterial suspension, and 7 mice died within 7 h (7/12).The results of this test indicated that there was a testicular infection of C.testosteroni in weak piglets and aborted fetuses.