Chang-Qing  Qiu, Xiao-An  Cao, Ji-Zhang  Zhou, Fu-Ying  Zheng, Guo-Zhen  Lin, Xiao-Wei  Gong, 
    Comparison and Analysis of Omp25 Genes of Nine <I>Brucella</I> Field Strains from Dairy Cows with Brucellosis in China,
    Veterinary Research,
    Volume 2,Issue 3,
    2008,
    Pages 47-51,
    ISSN 1993-5412,
    vr.2008.47.51,
    (https://makhillpublications.co/view-article.php?doi=vr.2008.47.51)
    Abstract: The full omp25 genes (642 bp) of 9 <I>Brucella</I> field strains from in 9 milk specimens sampled from dairy cows positive for brucellosis SAT on 9 dairy farms of different Provinces in China were molecularly characterized by PCR using the primers designed according to the published <I>B. abortus</I> omp25 gene sequence. Sequencing, comparison and analysis of the omp25 gene sequences cloned from the 9 <I>Brucella</I> field strains revealed a high degree of homology among their DNA sequences (&gt;98%), but all the sequences had some variations and none of them was same as the published sequences. The result revealed that <I>Brucella</I> field strains were mutated at various degrees in the different regions of China. The phylogenetic tree of omp25 gene has revealed the sequences of the field strains from Gansu and Shaanxi Provinces were closed to the <I>B. suis</I> (99.7 and 99.8% homology). Therefore, it is presumed that cows were affected with <I>B. suis</I>, which has been reported in China.
    Keywords: Brucella suis;omp25 gene;DNA sequence;dairy cattle