Theileria infection in domestic ruminants in northern Ethiopia

Identification of novel Theileria genotypes from Grant's gazelle

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One hundred percent of 65 Grant's gazelle blood samples were PCR-positive for Thelieria/Babesia.

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Sequencing of PCR amplicons revealed widespread Theileria co-infections.

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Isolates from singly infected animals fell into two Theileria subgroups.

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One of these subgroups clustered with Theileria ovis isolates from livestock.

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The gazelle Theileria lineages represent novel genotypes.

Blood samples collected from Grant's gazelles (Nanger granti) in Kenya were screened for hemoparasites using a combination of microscopic and molecular techniques. All 69 blood smears examined by microscopy were positive for hemoparasites. In addition, Theileria/Babesia DNA was detected in all 65 samples screened by PCR for a ~450-base pair fragment of the V4 hypervariable region of the 18S rRNA gene. Sequencing and BLAST analysis of a subset of PCR amplicons revealed widespread co-infection (25/39) and the existence of two distinct Grant's gazelle Theileria subgroups. One group of 11 isolates clustered as a subgroup with previously identified Theileria ovis isolates from small ruminants from Europe, Asia and Africa; another group of 3 isolates clustered with previously identified Theileria spp. isolates from other African antelope. Based on extensive levels of sequence divergence (1.2–2%) from previously reported Theileria species within Kenya and worldwide, the Theileria isolates detected in Grant's gazelles appear to represent at least two novel Theileria genotypes.

An epidemiological survey of bovine Babesia and Theileria parasites in cattle, buffaloes, and sheep in Egypt

Cattle, buffaloes, and sheep are the main sources of meat and milk in Egypt, but their productivity is thought to be greatly reduced by hemoprotozoan parasitic diseases. In this study, we analyzed the infection rates of Babesia bovis, Babesia bigemina, Theileria annulata, and Theileria orientalis, using parasite-specific PCR assays in blood-DNA samples sourced from cattle (n=439), buffaloes (n=50), and sheep (n=105) reared in Menoufia, Behera, Giza, and Sohag provinces of Egypt. In cattle, the positive rates of B. bovis, B. bigemina, T. annulata, and T. orientalis were 3.18%, 7.97%, 9.56%, and 0.68%, respectively. On the other hand, B. bovis and T. orientalis were the only parasites detected in buffaloes and each of these parasites was only found in two individual DNA samples (both 2%), while one (0.95%) and two (1.90%) of the sheep samples were positive for B. bovis and B. bigemina, respectively. Sequence analysis showed that the B. bovis Rhoptry Associated Protein-1 and the B. bigemina Apical Membrane Antigen-1 genes were highly conserved among the samples, with 99.3-100% and 95.3-100% sequence identity values, respectively. In contrast, the Egyptian T. annulata merozoite surface antigen-1 gene sequences were relatively diverse (87.8-100% identity values), dispersing themselves across several clades in the phylogenetic tree containing sequences from other countries. Additionally, the T. orientalis Major Piroplasm Surface Protein (MPSP) gene sequences were classified as types 1 and 2. This is the first report of T. orientalis in Egypt, and of type 2 MPSP in buffaloes. Detection of MPSP type 2, which is considered a relatively virulent genotype, suggests that T. orientalis infection may have veterinary and economic significance in Egypt. In conclusion, the present study, which analyzed multiple species of Babesia and Theileria parasites in different livestock animals, may shed an additional light on the epidemiology of hemoprotozoan parasites in Egypt.

Prevalence of piroplasms in small ruminants in North-West Tunisia and the first genetic characterisation of Babesia ovis in Africa

In this study, the prevalence of piroplasms in sheep and goats was assessed with Giemsa-stained blood smear examination, PCR and nested PCR-restriction fragment length polymorphism (RFLP) to identify Babesia and Theileria species, respectively, in 338 small ruminants (172 sheep and 166 goats) from three sites in North-West Tunisia during the 2011 summer season. The overall infection prevalence of piroplasms in Giemsa-stained blood smears was 3.2% (11/338), with a parasitaemia ranging from 0.01 to 0.05%. PCR detected two species, namely Babesia ovis (in sheep and goats) and Theileria ovis (in sheep), with an overall prevalence of 16.3%. The molecular prevalence of B. ovis was significantly higher in sheep than in goats (17.4% and 9%, respectively, p = 0.034). The same trend was observed for T. ovis in sheep and goats (5.8% and 0%, respectively, p = 0.004). Comparison of the partial sequences of the 18S ssu rRNA gene revealed 100% similarity amongst Babesia from sheep and goats. The single Theileria sequence in this study showed 100% similarity to T. ovis. A high similarity with all the blasted genotypes was reported for Theileria and Babesia sequences. This is the first molecular detection of B. ovis and genetic characterisation of small ruminants' piroplasms in Africa.