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Bovine theileriosis caused by several Theileria species including Theileria annulata, Theileria parva, Theileria orientalis, Theileria mutans, and Theileria sinensis is a significant hemoprotozoan tick-borne disease. Among these, Theileria species, T. annulata, which causes tropical theileriosis (TT), is regarded as one of the most pathogenic and is responsible for high mortality. At present, most conventional diagnostic methods for tropical theileriosis are time-consuming and laborious and cannot distinguish newfound T. sinensis in China. Therefore, a high sensitivity and specificity real-time quantitative PCR method based on the TA19140 target molecule was developed, and the method was found to be specific for T. annulata. No cross-reaction was observed with T. sinensis, T. orientalis, Babesia bovis, Babesia bigemina, or Hyalomma anatolicum which is negative for T. annulata. A total of 809 field samples from different regions of China were analyzed by using the developed qPCR and conventional PCR. The positive samples for T. annulata detected by real-time qPCR and conventional PCR were 66/809 (8.16%) and 20/809 (2.47%), respectively, and all positive amplicons by qPCR were confirmed by Sanger sequencing. The results showed that the developed qPCR for the T. annulata 19,140 gene was more sensitive than conventional PCR. In addition, we first discovered that TA19140 was mainly expressed at the schizont and merozoite stages of T. annulata by relative quantification. The protein encoded by the TA19140 gene may be used as a potential diagnostic antigen for tropical theileriosis. In conclusion, a real-time quantitative PCR diagnostic method targeting the TA19140 gene was successfully established and could be used for both the quantitative and qualitative analysis of T. annulata infection from cattle and vector ticks, which will greatly help to control and diagnosis of tropical theileriosis. [ABSTRACT FROM AUTHOR]

Theileria species, with a broad geographic distribution, infect a wide range of both domestic and wild animals and are transmitted by ixodid ticks. Currently, there is no comprehensive report regarding the distribution of Theileria spp. in the eastern Tibetan Plateau, especially in Ganze Tibetan autonomous prefecture (153,700 km2) and Ngawa Tibetan and Qiang autonomous prefecture (84,242 km2) of Sichuan province, China. In this study, we collected blood samples from yaks (n = 144) (Bos grunniens), Tibetan sheep (n = 92), and Tibet horses (n = 142) in Ganze and Ngawa. Theileria sinensis, T. luwenshuni, and T. equi were the dominant Theileria species detected in yaks, Tibetan sheep, and horses with the total infection rates of 25.7% (37/144), 75.0% (69/92), and 51.4% (73/142), respectively. For ectoparasites, T. luwenshuni was the only Theileria species detected in sheep keds (Melophagus ovinus) with an infection rate of 30.8% (8/26). The total infection rates of T. sinensis in Haemaphysalis qinghaiensis, Dermacentor everestianus, and Rhipicephalus microplus were 34.6% (36/104), 34.0% (17/50), and 51.3% (58/113), respectively. Theileria spp., belonging to T. sergenti/buffeli/orientalis group, were only detected in R. microplus collected in Danba county of Ganze with a total infection rate of 39.9% (19/48). Our results provide important data of the epidemiology of Theileria spp. in livestock and ectoparasites and will assist with the implementation of measures to control theileriosis transmission in eastern Tibetan Plateau, China. [ABSTRACT FROM AUTHOR]

Tick-borne diseases (TBDs) impose a significant constraint to livestock production world widely. In this paper, we presented a case of TBD in a cattle farm in Henan, China. 35 blood samples (7 samples sent by veterinarian, 28 samples gathered by our colleagues) were collected from ill, surviving and asymptomatic cattle and microscopic observation and PCR assays were conducted to characterize the pathogens. Genus Ixodes feeding on these cattle were collected and identified. Theileria annulata -like and Anaplasma marginale -like pathogens were observed in the blood smears stained with Giemsa staining under microscope. Furthermore, 5 out of 7 cattle blood samples were found to be positive for T. annulata by PCR. In the 28 blood specimens, three were positive for T. annulata , while A. marginale DNA was detected in nine blood DNA samples. Besides, 56 ticks feeding on cattle were collected from this farm and were all identified as Rhipisephalus microplus , meanwhile, 10 of them were found to be positive for A. marginale . In addition, phylogenetic analysis of the msp4 gene sequences of A. marginale obtained in this study showed that the isolate from cattle (KX840009) fell in the same clade with that of R . microplus (KX904527), sharing 100% similarity. To the best of our knowledge, this is the first confirmed report of outbreak of theileriosis/anaplasmosis in cattle farms in Henan, China. [ABSTRACT FROM AUTHOR]

Abstract: Theileriosis is an important tick-borne hemoprotozoan disease, which can cause severe economic loss in animal husbandry. In this paper, one hundred peripheral blood samples of goats and sheep from southeastern China were examined for the Theileria infection. A region of Theileria 18S rRNA gene was amplified by nested PCR in 26 samples. All the nested PCR amplicons were cloned and sequenced. Alignment analysis has shown that these sequences are highly homologus to each other with identities from 99.2% to 100%. Blast the sequences against NCBI database indicated 99% homology with Theileria sp. China 1 (Theileria luwenshuni). Phylogenetic tree has also shown that the newly identified Theileria are in the same clade with T. luwenshuni. The results have revealed a relatively high prevalence of Theileria in some areas of southeastern China and little genetic diversity in these infections. [Copyright &y& Elsevier]

The pathogenic protozoan parasite Theileria uilenbergi is one of the causative agents of theileriosis in small ruminants in China. The infection results in great economical losses in the northwest part of China. Efforts are underway to establish an enzyme-linked immunosorbent assay (ELISA) based on a T. uilenbergi immunodominant recombinantly expressed protein using different approaches in order to perform epidemiological studies in the area. In this study, we describe the possible use of the clone-9 protein for this purpose, which was identified as a potential immunogenic piroplasm protein by random sequencing of cDNA library clones followed by bioinformatic analyses. The clone-9 gene was partially recombinantly expressed and used for the development of an indirect ELISA for the detection of circulating antibodies in sera of T. uilenbergi-infected sheep. No cross-reactivity was observed in serum from animals infected with Theileria lestoquardi. The cut-off was calculated at 48.6% positivity using 25 serum samples from uninfected animals. A total of 101 field samples collected from an endemic area in China were used to evaluate the clone-9 ELISA for its use in the field. [ABSTRACT FROM AUTHOR]

Abstract: Theileriosis of small ruminants in the northwest of China is a protozoan disease that restricts the development of the livestock industry. The disease is caused by infection with Theileria uilenbergi and Theilerialuwenshuni, both of which are transmitted by ixodid Heamaphysalis ticks. The development of serological tools as a means of integrated control of the disease is an urgent and important requirement. Here we describe the identification and partial recombinant expression of a T.uilenbergi immunodominant protein (TuIP), which was identified by immunoscreening of a merozoite cDNA library. Using the recombinant TuIP (rTuIP), a novel indirect ELISA was established using 329 negative serum samples to determine the cut-off value. The internal quality control revealed satisfactory stability and repeatability of the assay. Preliminary validation using 128 positive and 48 negative reference samples demonstrated that the rTuIP ELISA is able to detect T. uilenbergi infection with high sensitivity and specificity. No cross-reactivity was found in sera from animals infected with Theileria lestoquardi, Babesia sp. China or Anaplasma ovis. Furthermore, circulating antibodies were detected in sera collected from endemic regions in China. Analyses of the antibody responses of experimentally infected animals demonstrated that tick infestation resulted in a sharply rising and stronger production of specific antibodies against TuIP while inoculation with infected blood induced an earlier production of TuIP-specific antibodies. The persistence of the TuIP-specific antibodies lasted more than 100days p.i. These data indicate the usefulness of the TuIP antigen for the development of diagnostic methods and as a potential candidate for vaccine design. [Copyright &y& Elsevier]

Sheep and goats in northwest China suffer from theileriosis from infection with Theileria sp. (China), resulting in large economic losses. To investigate the immune response to infection with Theileria sp. (China), parameters of cellular and humoral immunity of experimentally infected sheep against two recombinantly expressed Theileria proteins were investigated. The in vitro proliferative response of blood mononuclear cells to a recombinant T. annulata membrane protein and a recombinant Theileria sp. (China) homologue to T. annulata surface protein, both putative membrane proteins, was significantly elevated and significant amounts of specific immunoglobulins were produced against both. [ABSTRACT FROM AUTHOR]

The Gannan Tibet Autonomous Region is the biggest and most important stock-raising region of Gansu Province, People's Republic of China. Many sheep and goats from this region suffer from Theileria challenge each year, resulting in inestimable economical losses. A first large-scale serological investigation by enzyme-linked immunosorbent assay of ovine theileriosis in this region was performed by testing a total of 1,165 sera samples collected from seven districts of three counties. The results showed that seroprevalence of reactive antibodies varied from 27.8 to 83.3%, whereby the average was 70.1% in the disease-endemic areas. Another 44 sera samples collected every month from July 2004 to June 2005 from a stable flock of sheep in Biandu Town of Lintan County were analysed to evaluate the seasonal kinetics of anti-Theileria antibodies. The results indicated that anti-Theileria antibody seroprevalence rose from March, reaching a peak value of 68.2% in May, declining in October and reaching the lowest value of 36.4% in January. The data indicate that seroprevalence of anti-Theileria antibodies correlate to the known activities of its transmitting vector and also imply that chemical therapy of animals should be performed during May to June in these Theileriosis-epidemic regions. [ABSTRACT FROM AUTHOR]

Theileria is a tick-borne, intracellular protozoan parasite of worldwide economic and veterinary importance in small ruminants. Here, an enzyme-linked immunosorbent assay (ELISA) was developed based on Theileria luwenshuni recombinant surface protein (rTlSP) and was used in the standardization and validation of an ELISA for the detection of circulating antibodies against ovine and caprine theileriosis. A total of 233 sera samples were used for the calculation of the cut-off value which served as a threshold between the positive and the negative sera. When the positive threshold was chosen as 19% of the specific mean antibody rate, the specificity was 97.9%, and the sensitivity was 97.1%. There was a cross-reaction with sera against Theileria uilenbergi and Theileria ovis, and no cross-reaction with sera against Babesia spp. in the ELISA and Western blotting. Two hundred forty samples collected from sheep in Gansu province were detected with blood smears and ELISA, respectively. The results showed that the positive rate of Theileria infection in Gansu province were 63.75% with rTlSP-ELISA, and 46.67% with blood smears, respectively. Our test proved that the rTlSP ELISA is suitable to diagnose Theileria infection and could be used in serological surveys to map out the prevalence of ovine and caprine theileriosis., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Abstract: Tropical theileriosis, a tick borne disease of cattle caused by the protozoan Theileria annulata, was widely distributed in northern China causing great economical losses before the 1980’s. In the 1960’s blood passaging, irradiation and in vitro culture of parasite were used for the development of attenuated vaccine. Two lines of the schizont stage were obtained which both provided sufficient protection against tick infestation or blood challenge in experimental and field trials. A gelatin protection technique allowed storage at 4°C, significantly prolonged shelf life and permitted transport without a cold chain. The vaccines were commercialized and widely administered in epidemic areas, leading to control of T. annulata infection in China. [Copyright &y& Elsevier]