Department of Veterinary Hygiene and Public Health, School of Veterinary Medicine and Animal Science, Universidade Estadual Paulista - UNESP, Botucatu, São Paulo, Brazil; Department of Production Animal Health, Faculty of Veterinary Medicine, University of Calgary, Alberta, Canada.
Vet Microbiol. 2013 Dec 27;167(3-4):708-12. doi: 10.1016/j.vetmic.2013.08.019. Epub 2013 Sep 1.
Nocardia spp. infections can cause severe damage to the mammary gland due to suppurative pyogranulomatous lesions and lack of clinical cure in response to conventional antimicrobial therapy. Although Nocardia infections are considered relatively uncommon in cows, there has been an apparent worldwide increase in the incidence of bovine mastitis caused by Nocardia spp, perhaps due to environmental transmission of this ubiquitous pathogen. The objectives of present study were to determine: (i) species distribution of 80 Nocardia isolates involved in bovine mastitis (based on molecular methods); and (ii) antimicrobial susceptibility pattern of all isolates from three geographical areas in Brazil. In this study, Nocardia nova (80%) was the most frequently isolated species, followed by Nocardia farcinica (9%). Additionally, Nocardia puris, Nocardia cyriacigeorgica, Nocardia veterana, Nocardia africana, and Nocardia arthritidis were detected using 16S rRNA sequencing. This is apparently the first report of N. puris, N. veterana, N. cyriacigeorgica, N. arthritidis and N. africana in association with bovine mastitis. Based on the disk diffusion test, isolates were most frequently resistant to cloxacillin (75%), ampicillin (55%) and cefoperazone (47%), whereas few Nocardia spp. were resistant to amikacin, cefuroxime or gentamicin.
诺卡氏菌属感染可导致化脓性肉芽肿瘤病变，对常规抗菌治疗反应不佳，从而对乳腺造成严重损害。虽然诺卡氏菌感染在奶牛中被认为相对少见，但由于这种普遍存在的病原体的环境传播，诺卡氏菌引起的奶牛乳腺炎的发病率在全球范围内明显增加。本研究的目的是确定：（i）参与奶牛乳腺炎的 80 株诺卡氏菌分离株的种分布（基于分子方法）；（ii）来自巴西三个地区的所有分离株的抗菌药物敏感性模式。在这项研究中，最常分离到的物种是新诺卡氏菌（80%），其次是星形诺卡氏菌（9%）。此外，还通过 16S rRNA 测序检测到诺卡氏 puris、诺卡氏 cyriacigeorgica、诺卡氏 veterana、诺卡氏 africana 和诺卡氏 arthritidis。这显然是首次报道 N. puris、N. veterana、N. cyriacigeorgica、N. arthritidis 和 N. africana 与奶牛乳腺炎有关。根据圆盘扩散试验，分离株对氯唑西林（75%）、氨苄西林（55%）和头孢哌酮（47%）的耐药性最高，而少数诺卡氏菌对阿米卡星、头孢呋辛或庆大霉素耐药。
