Genetic characterization and molecular survey of Babesia bovis, Babesia bigemina and Babesia ovata in cattle, dairy cattle and yaks in China

Abstract

BackgroundBabesiosis is an important haemoparasitic disease, caused by the infection and subsequent intra-erythrocytic multiplication of protozoa of the genus Babesia that impacts the livestock industry and animal health. The distribution, epidemiology and genetic characterization of B. bigemina, B. bovis, and B. ovata in cattle in China as well as the prevalence of these protozoan agents were assessed.MethodsA total of 646 blood specimens from cattle, dairy cattle and yaks from 14 provinces were collected and tested for the presence of the three Babesia species via a specific nested PCR assay based on the rap-1 and ama-1 genes. The PCR results were confirmed by DNA sequencing. Gene sequences and the genetic characterization were determined for selected positive samples from each sampling area.ResultsOf a total of 646 samples, 134 (20.7 %), 60 (9.3 %) and 10 (1.5 %) were positive for B. bovis, B. bigemina and B. ovata infections, respectively. Mixed infections were found in 7 of 14 provinces; 43 (6.7 %) samples were infected with B. bovis and B. bigemina. Three samples (0.5 %) exhibited a co-infection with B. bovis and B. ovata, and 6 (0.9 %) were infected with all three parasites. The rap-1a gene of B. bovis indicated a high degree of sequence heterogeneity compared with other published rap-1a sequences worldwide and was 85–100 % identical to B. bovis rap-1a sequences in Chinese isolates. B. bigemina rap-1c and B. ovata ama-1 genes were nearly identical, with 97.8–99.3 % and 97.8–99.6 % sequence identity, respectively, in GenBank.ConclusionsPositive rates of B. bovis and B. bigemina infection are somewhat high in China. The B. bovis infection in yaks was first reported. The significant sequence heterogeneity in different variants of the rap-1a gene from Chinese B. bovis isolates might be a great threat to the cattle industry if RAP-1a protein is used as immunological antigen against Babesia infections in China. The data obtained in this study can be used to plan effective control strategies against babesiosis in China.Electronic supplementary materialThe online version of this article (doi:10.1186/s13071-015-1110-0) contains supplementary material, which is available to authorized users.

Genetic Analysis of Babesia Isolates from Cattle with Clinical Babesiosis in Sri Lanka

“…The 371-bp ama-1 sequences from cows R and V (GenBank accession number LC385894) were identical to each other and to the long ama-1 gene fragment initially isolated from cow R (GenBank accession number LC385893). Phylogenetic trees based on the ama-1 gene were used to investigate the evolutionary relationships of apicomplexan parasites, such as species of Plasmodium and Babesia (61,(63)(64)(65). In a phylogenetic construction used to investigate the positions of Babesia sp.…”

Molecular investigation of piroplasma infection in white yaks ( Bos grunniens ) in Gansu province, China

“…The prevalence of B. bigemina was first detected in yaks from Aba Tibetan and Qiang Autonomous Prefecture in 1978 (Yu et al, 1985). Until 2000, the investigations of piroplasmosis were carried out in yaks targeted on the given in yaks using molecular diagnostic techniques or ELISA Qin et al, 2016;Niu et al, 2015). These data suggested yaks seriously suffered from the infection of piroplasms that possibly have impeded the productivity improvement of yak industry.…”

“…In recent years, several papers reported the prevalence of piroplasms in yaks using serological and molecular methods. The results showed that yaks suffered from the serious infection of piroplasmosis, B. bigemina (5.32-24.18%) Qin et al, 2016;Saravanan et al, 2013), B. bovis (13.33%) (Niu et al, 2015), T. sinensis (60.15%) . (Qin et al, 2015).…”

Molecular survey of piroplasm species from selected areas of China and Pakistan

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