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Infections of small ruminants with Anaplasma, Theileria and Babesia species are widely distributed in the old world and are of great economic impact. In Iraq, data on disease occurrence in sheep caused by above-mentioned infectious agents are scarce. This study provides information on various haemoparasitic agents infecting sheep in the Kurdistan Region, Iraq, using molecular diagnostic tools. Altogether, 195 samples originating from three governorates in the Kurdistan Region, namely Duhok, Erbil and Sulaimaniya, were analysed. The following pathogens were identified: Anaplasma ovis (62.6%), Theileria ovis (14.35%), T. lestoquardi (7.7%), T. uilenbergi (5.6%) and Babesia ovis (1.5%). T. uilenbergi is detected for the first time in Iraq. Coinfection of sheep with different pathogens could be observed in this study, and it was found that 45 of 195 (23%) of the samples contained more than one pathogen. Even triple-positive samples were identified in 3% of the investigated animals. In conclusion, we confirm the coinfection of sheep with various haemoparasitic pathogen species in the Kurdistan Region of Iraq. Further investigations are needed to reveal the epidemiology of the diseases, the respective tick vectors, and, in the case of coinfection, pathogens' interaction and possible cross-protection., (© 2013 Blackwell Verlag GmbH.)

A loop-mediated isothermal amplification (LAMP) assay was developed for the diagnosis of Theileria lestoquardi infection. The primers were designed based on the clone-5 sequence of T. lestoquardi. The specificity and sensitivity of the assay were established. Analysis of the specificity showed that the selected LAMP primers amplified the target sequence from T. lestoquardi DNA successfully, while no amplification was seen with DNA from Theileria annulata, Theileria ovis, Babesia ovis, Anaplasma ovis, or ovine genomic DNA. The specificity of the LAMP product was further confirmed by restriction digestion and sequencing. The sensitivity of the LAMP assay was analyzed in comparison to PCR resulting in a detection limit of 10 fg/μl of plasmid DNA containing the clone-5 sequence. The suitability for utilizing the LAMP assay in the field for the diagnosis of T. lestoquardi infection was tested on 100 field samples collected in Sudan and compared with results obtained by PCR. The relative specificity and sensitivity of the established LAMP assay was determined to be 92.1% and 87.5%, respectively, indicating that it may be regarded as an alternative molecular diagnostic tool to PCR which could be used for epidemiological surveys on T. lestoquardi infection.

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.

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., (2009 Australian Society for Parasitology Inc. Published by Elsevier Ltd. All rights reserved.)

In this study potential molecular markers for identification of attenuation in a Theileria lestoquardi-infected cell line to be used in vaccination trials were identified. Two markers associated with attenuation in Theileria annulata vaccine strains were analyzed (metalloproteinase activity and TNF? mRNA expression). The result showed a decreased activity of MMP 9 and decreased mRNA expression of TNF? with increasing passage number. Suppression subtractive hybridization was used to identify potential new markers of attenuation. Random screening revealed nine differentially expressed genes, one from the parasite and eight from the host. Quantitative real time-PCR confirmed mRNA expression of the parasite vacuolar H+ATPase to be downregulated at higher passages.