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The range of the protozoan parasite Theileria parva, which causes East Coast fever in cattle, has been expanding to countries where it has not previously been detected, as a result of cross-border domestic cattle movement. Countries where T. parva has not previously been observed until recently include Cameroon and South Sudan. This raises the issue of the conservation of the p104 antigen gene, on which the nested PCR assay that is widely used for T. parva surveillance in the blood of infected cattle is based. We sampled 40 isolates from six countries widely distributed across the geographical range of the parasite, including eastern, central and southern Africa, for p104 sequence polymorphism. These included parasites from both domestic cattle and the Cape buffalo (Syncerus caffer) wildlife reservoir. The most frequent allelic variants were present in cattle transmissible isolates from multiple widely separated geographical regions in Zambia, Uganda, Kenya, Tanzania, Rwanda and South Africa. These frequent p104 variants were also present in the three component stocks of the Muguga cocktail used for the infection and treatment live immunisation procedure to control T. parva in the field. Other isolates exhibited unique alleles. This includes some of the p104 sequences from Cameroon, which is outside the known range of the Rhipicephalus tick vector and whose origin is therefore unclear. The nested primer oligonucleotides used to generate the amplicons were universally conserved in cattle-derived parasites and a majority of buffalo-derived isolates across the geographical range of the parasite. However, some rare South African buffalo–derived isolates exhibited one or two mismatches with the primer sequences. It therefore remains possible that some p104 alleles may be so divergent that they do not amplify with the current diagnostic primers and are not detectable in surveys, hence the need for increasing knowledge of genetic heterogeneity of diagnostic targets. There was no evidence for positive selection among those p104 mutations that resulted in residue changes. Importantly, the data indicate that the p104-based PCR detection assay should be effective across the majority of the range of T. parva, and if the one or two mismatches are shown in future to result in the primers annealing less efficiently, then the assay can be further improved by introduction of degenerate bases to enable amplification of the less frequent South African buffalo–derived variant p104 genes. [ABSTRACT FROM AUTHOR]

Rhipicephalus appendiculatus is the major tick vector of Theileria parva, an apicomplexan protozoan parasite that causes the most economically important and lethal disease of cattle in East and central Africa. The African cape buffalo (Syncerus caffer) is the major wildlife host of T. parva from southern Uganda and Kenya to southern Africa. We show herein that R. appendiculatus appears to be absent from the two largest national parks in northern Uganda. Syncerus caffer is common in both of these national parks, specifically Murchison falls (MFNP) and Kidepo Valley (KVNP). We re-confirmed the previously reported absence of T. parva in buffalo sampled in the two northern parks based on RLB data using a nested PCR based on the T. parva p104 gene. By contrast, T. parva-infected R. appendiculatus ticks and parasite-infected buffalo were present in Lake Mburo (LMNP) in South central Uganda. This suggests that the distribution of R. appendiculatus, which is predicted to include the higher rainfall regions of northern Uganda, may be limited by additional, as yet unknown factors. [ABSTRACT FROM AUTHOR]

Bovine theileriosis, a tick-borne protozoan disease caused by Theileria annulata, Theileria orientalis and Theileria sinensis, is widespread in China and is a serious economic problem for the Chinese livestock industry. In this study, recombinant major piroplasma surface proteins (MPSP) of T. annulata, T. orientalis and T. sinensis based on MPSP genes were expressed in Escherichia coli BL21(DE3). The immunogenicity and specificity of the three purified recombinant MPSP proteins were evaluated with the reference positive sera of T. annulata, T. orientalis, T. sinensis, Babesia bovis, B abesia bigemina, Babesia major, Babesia motasi, Theileria luwenshuni, Theileria uilenbergi and Anaplasma ovis using an enzyme-linked immunosorbent assay (ELISA) or western blotting. The results showed that all three of the rMPSP proteins had a strong reaction with the sera from cattle infected with T. annulata, T. orientalis and T. sinensis via western blotting but not with other piroplasma and Anaplasma species . Then, the rMPSP protein of T. sinensis was used to develop an iELISA for detecting the three Theileria species infections. The specificity and sensitivity were 95.7 and 95.5 %, respectively, with a threshold of 28.8 % of the specific mean antibody rate (AbR). Finally, 2473 field-collected bovine sera, from 42 prefectures of 17 provinces in China, were tested using the ELISA to evaluate the prevalence of bovine theileriosis, and the average positive rate was 43.6 %. The developed iELISA could be a suitable tool to detect the three bovine Theileria species, and the data also provided important information regarding the current prevalence of bovine theileriosis in China. [ABSTRACT FROM AUTHOR]

Theileriosis is an economically important hemoprotozoal disease with high morbidity and mortality in cattle. The present study reported the pathological features of a natural outbreak of tropical bovine theileriosis due to Theileria annulata in Fars Province, southern Iran. T. annulata was confirmed by the presence of T. annulata piroplasms in the blood smears and also by polymerase chain reaction test. On necropsy, pale mucous membranes and petechial and ecchymotic hemorrhages in the mucosal and serosal surfaces together with lymphadenopathy were observed. The liver was friable, yellowish, and larger than normal. Hemorrhages and punched-out ulcers were observed in the abomasal mucous membrane. Severe petechial hemorrhages were seen in the skin particularly in the hairless areas. Pulmonary edema and emphysema with petechial and ecchymotic hemorrhagic foci in the lungs were evident. The main histological changes were proliferation of lymphocytes in the lymph nodes and proliferation of macrophages, lymphocytes, and plasma cells in the spleen, Peyer's patches, portal tracts of the liver, and interstitial tissue of the kidneys. The mucous membrane of the abomasum showed numerous multifocal areas of necrosis and ulceration, and the submucosal area and lamina propria adjacent to these lesions showed hyperemia and hemorrhages, with mononuclear cell infiltration. The skin showed multifocal necrotic changes, petechial and ecchymotic hemorrhages, and chronic dermatitis. The schizonts of Theileria were evident in the cytoplasm of the lymphocytes and macrophages of the lymph nodes, spleen, and skin. Molecular examination revealed that these animals were infected with T. annulata. The present study describes the clinicopathological findings of bovine tropical theileriosis in an unpredictable weather condition. [ABSTRACT FROM AUTHOR]

Abstract  This study was conducted to assess the pattern of changes and the relative value of acute phase proteins (haptoglobin (Hp), serum amyloid A (SAA), ceruloplasmin and fibrinogen) in bovine tropical theileriosis. The diseased group comprised 50 dairy Holstein cattle, 2−3 years old, naturally infected with Theileria annulata. Infected animals were divided into four subgroups with different parasitemia rates (5%). As a control group, 20 uninfected cattle were also sampled. Blood samples were collected and all measurements were done using validated methods. There were significant differences in red blood cells (RBCs), packed cell volume (PCV), hemoglobin (Hb) and concentrations of Hp, SAA, ceruloplasmin and fibrinogen between healthy cattle and those infected with T. annulata with different parasitemia rates (P 5.68 μg/ml for SAA, >0.16 g/l for Hp, >0.064 g/l for ceruloplasmin and >4.00 g/l for fibrinogen with corresponding 84% sensitivity and 100% specificity for SAA, 76% sensitivity and 100% specificity for Hp, 84% sensitivity and 80% specificity for ceruloplasmin and 40% sensitivity and 100% specificity for fibrinogen. SAA had the highest sensitivity and specificity and was diagnosed to be a suitable indicator of APPs changes in bovine theileriosis. [ABSTRACT FROM AUTHOR]