Gharaibeh Saad, Laibinis Victoria, Wooten Ruth, Stabler Lisa, Ferguson-Noel Naola
Faculty of Veterinary Medicine, Jordan University of Science and Technology, Irbid, Jordan 22110.
Avian Dis. 2011 Jun;55(2):212-6. doi: 10.1637/9526-091510-Reg.1.
Two groups of Mycoplasma gallisepticum (MG) isolates (n = 24) from Jordan were analyzed by molecular methods and compared with other Middle Eastern isolates, related international isolates, and reference strains. The first group (n = 19) was isolated from July 2004 to January 2005 (isolation period A), and the newer group (n = 5) from June 2007 to April 2008 (isolation period B). The groups of isolates are from chicken flocks from northern Jordan, but are not from the same farms. None of the flocks were vaccinated for MG. Random amplified polymorphic DNA analysis, targeted sequencing of the partial MG cytadhesin 2 (mgc2), and the MG 16S-23S rRNA intergenic spacer region (IGSR) divided the Jordanian isolates into two groups. All of the 19 isolates from time period A, in addition to two isolates from time period B, were indistinguishable from the F strain. Three of five isolates from time period B were characterized as wild types and were indistinguishable from each other. The wild-type field strain was readily distinguished from the F strain. It was 91% and 96.4% similar to the F strain based on Clustal-W alignments of sequences of mgc2 and IGSR, respectively. Sequence similarity of mgc2 gene of the Jordan wild-type strain to isolates from Israel and Egypt ranged from 96.5% to 100%, whereas for IGSR it was 99.4%-100%. We theorize that the F-strain live MG vaccine, commonly used in Jordan prior to 2007, was transmitted to nonvaccinated poultry in the region and was a predominant genotype during time period A.
采用分子方法对来自约旦的两组鸡毒支原体（MG）分离株（n = 24）进行分析，并与其他中东地区分离株、相关国际分离株及参考菌株进行比较。第一组（n = 19）于2004年7月至2005年1月分离得到（分离期A），较新的一组（n = 5）于2007年6月至2008年4月分离得到（分离期B）。这些分离株来自约旦北部的鸡群，但并非来自同一养殖场。所有鸡群均未接种过MG疫苗。通过随机扩增多态性DNA分析、MG细胞黏附素2（mgc2）部分序列的靶向测序以及MG 16S - 23S rRNA基因间隔区（IGSR）分析，将约旦分离株分为两组。分离期A的所有19株分离株，以及分离期B的两株分离株，与F株无法区分。分离期B的5株分离株中有3株被鉴定为野生型，且彼此无法区分。野生型田间菌株很容易与F株区分开来。基于mgc2和IGSR序列的Clustal - W比对，其与F株的相似性分别为91%和96.4%。约旦野生型菌株mgc2基因与以色列和埃及分离株的序列相似性在96.5%至100%之间，而IGSR的相似性为99.4% - 100%。我们推测，2007年之前约旦常用的F株活MG疫苗传播到了该地区未接种疫苗的家禽中，并在分离期A成为主要基因型。
