However, little work has been performed on the molecular detection of A. marginale strains have been identified by the analysis of msp1 α genotypes (De la Fuente et al. marginale in South Africa is known to be high (Mtshali et al. centrale that is closely related to the vaccine strain was associated with a case of clinical disease in a bovine in Europe (Carelli et al. The vaccine strain can cause reactions in adult cattle of susceptible breeds (Bigalke 1980 Pipano 1976) and it has been reported to cause severe anaplasmosis in splenectomised adult cattle (Kuttler 1966 Pipano, Mayer & Frank 1985). marginale and might not be effective against antigenically diverse, highly virulent stocks of A. However, this vaccine causes variable protection against A. marginale in many countries, including South Africa (De Waal 2000 Melendez et al. centrale is used to immunise cattle against A. It causes a milder form of anaplasmosis, and a live blood vaccine containing A. centrale, commonly referred to as Anaplasma centrale, was first isolated in South Africa by Sir Arnold Theiler (Theiler 1911) who originally classified it as ' A. marginale in South Africa: Rhipicephalus decoloratus, Rhipicephalus microplus, Rhipicephalus evertsi evertsi, Rhipicephalus simus and Hyalomma marginatum rufipes (Potgieter 1979 Potgieter & Van Rensburg 1980).Īnaplasma marginale subsp. Five tick species have been implicated in the transmission of A. Anaplasmosis is widely distributed around the world, and in South Africa, it is endemic in most of the cattle-farming areas (De Waal 2000 Marufu et al. The clinical manifestations of anaplasmosis include fever, progressive anaemia and icterus, and the disease has a case fatality rate of up to 36% (Losos 1986). We propose the use of the duplex qPCR assay in future studies as it is more sensitive and offers the benefits of quantification and multiplex detection of both Anaplasma spp.īovine anaplasmosis is a tick-borne disease of cattle caused by the intra-erythrocytic rickettsia, Anaplasma marginale (Theiler 1910). marginale msp1 β sequences, resulting in false negatives. The results indicated sequence variation in the internal forward primer (AM100) area amongst the South African A. To explain this discrepancy, the target sequence region of the nPCR assay was evaluated by cloning and sequencing the msp1 β gene from selected field samples. marginale using nPCR but positive using qPCR. marginale-positive samples, 13 samples tested negative for A. Although the results of the qPCR and nPCR tests were in agreement for the majority (38) of A. centrale-positive samples than the other assays, either as single or mixed infections. centrale plasmid DNA by the RLB, nPCR and qPCR assays respectively. marginale plasmid DNA were 2500 copies by the RLB assay, 250 copies by the nPCR and qPCR assays and 2500, 250 and 25 copies of A. centrale infections in cattle ( n = 66) in South Africa. We evaluated the ability of the reverse line blot (RLB) hybridisation assay, two nested polymerase chain reaction (nPCR) assays and a duplex real-time quantitative polymerase chain reaction (qPCR) assay to detect A. Several nucleic acid-based assays have been developed for detecting Anaplasma marginale and Anaplasma centrale in vectors and hosts, making the choice of method to use in endemic areas difficult. VINational Zoological Gardens, Pretoria, South Africa VDepartment of Veterinary Microbiology and Pathology, Washington State University, United States IVDepartment of Veterinary Services, Ministry of Agriculture and Livestock, Zambia IIIBiotechnology Platform, Agricultural Research Council, South Africa IIDepartment of Genetics, University of Pretoria, South Africa IDepartment of Veterinary Tropical Diseases, University of Pretoria, South Africa Baxter I, II Paidashe Hove I, III Chimvwele N. Comparison of three nucleic acid-based tests for detecting Anaplasma marginale and Anaplasma centrale in cattle

Pjet vector in serial cloner