Molecular identification of Theileria and Babesia in sheep and goats in the Black Sea Region in Turkey

Prevalence of Theileria ovis in sheep and goats in northwestern Saudi Arabia with notes on potential vectors

The prevalence of Theileria spp. infecting sheep and goats were investigated in two cities and surroundings in northwest Saudi Arabia. Blood samples from 403 sheep and goats from Madina (n = 201) and Tabuk (n = 202) cities (177 from sheep and 226 from goats) were investigated. Blood samples were examined microscopically for the presence of intraerythrocytic bodies suggestive of Theileria as well as they were investigated using molecular techniques. DNA was extracted from blood and ticks and subjected to polymerase chain reaction amplification using specific primers. The primers used amplified a fragment of the 18S rRNA region (450 bp) targeting the hypervariable region IV. A total of 63 ticks belonging to five species were collected from sheep and goats for determination of their involvement of lifecycle of Theileria. Ticks were identified morphologically and confirmed molecularly utilizing cytochrome oxidase C subunit 1 gene (COXI) amplification. The results indicated that: microscopic examination revealed 24 (6%) of the samples investigated showed intraerythrocytic bodies suggestive of Theileria. Positive samples were only obtained from sheep whereas goats yielded negative results. A total of 33 (18.6%) sheep samples were positive for Theileria infection using polymerase chain reaction targeting the partial 18S rDNA and DNA sequencing. Theileria infection was more prevalent in animals that were less than 2 years of age compared with older animals. There was no difference in the prevalence of the infection between male and female sheep in both cities. All positive sheep were detected during the summer and none of the samples collected during the winter were positive. Phylogenetic analysis revealed that the sequences obtained from Theileria species reported in the present study grouped with sequences from Theileria ovis from different countries. Ticks were identified as Hyalomma dromedarii, Hyalomma, marginatum, Hyalomma impeltatum and Hyalomma anatolicum anatolicum. T. ovis DNA was detected from Hyalomma dromedarii and Hyalomma impeltatum suggesting that they are potential vectors of this piroplasm in sheep from Madina and Tabuk cities. This report is considered the first report of T. ovis infecting sheep from Madina and Tabuk, furthermore, it is the first report determining the vectors responsible for transmission of the infection in sheep in northwest Saudi Arabia. The data generated from this study will undoubtedly pave the way for the detection and control of ovine and caprine theileriosis in Madina and Tabuk regions.

Experimental infection of purebred Saanen goats high pathogenicity and virulence of Babesia aktasi

Small ruminant babesiosis remains a neglected disease despite causing significant economic losses to sheep and goat herds in many regions around the world. The pathogenesis and clinical manifestations of ovine babesiosis are well-known, but there is a lack of information regarding caprine babesiosis. Since the discovery of the first Babesia spp. in 1888, several species/subspecies/genotypes, including Babesia aktasi, have been described. Our recent molecular survey revealed that the parasite is highly prevalent (22.5%) in indigenous goats from Mediterranean region of Türkiye. The aim of this experimental study was to determine the pathogenicity and virulence of B. aktasi in immunosuppressed (n = 5) and immunocompetent (n = 7) purebred Saanen goats. The goats were experimentally infected with fresh B. aktasi infected blood, and examined for clinical, parasitological, hematological, and serum biochemical findings throughout the infection. Following the parasite inoculation, intra-erythrocytic parasites were detected from the 1st day post-infection, followed by an increase in rectal temperature and parasitemia. The parasitemia was detected ranging from 4.3% to 33.5% in the immunosuppressed group, while it was 2.1% to 7.6% in the immunocompetent. Severe clinical symptoms characterized by anemia, jaundice, and hemoglobinuria developed in both groups. A statistically significant inverse correlation was observed between the increase in parasitemia and RBC, WBC, HCT, and Hb values in the goats compared to pre-infection levels. Values of AST, ALT, GGT, Total bilirubin, and Albumin showed a significant increase, with all the immunosuppressed goats dying on the 4th and 7th days post-infection, while four out of seven immunocompetent goats died on between 6-8th days. Severe edema in the lungs, frothy fluid in the trachea, jaundice in the subcutaneous and mesenteric fat, and dark red urine were detected in necropsy. The results obtained in this study demonstrated that B. aktasi was highly pathogenic to purebred Saanen goats. Current work assures valuable insights into the pathogenesis and virulence of B. aktasi and serves as a foundation for future studies to develop effective control strategies against caprine babesiosis.

Development and Evaluation of a Semi-Nested PCR Method Based on the 18S ribosomal RNA Gene for the Detection of Babesia aktasi Infections in Goats

We developed and evaluated a semi-nested PCR assay for the detection of Babesia aktasi infection in goats based on the sequence of the B. aktasi 18S ribosomal RNA gene. Following in silico screening, the specificity of the primers was assessed using reference DNA samples, including B. ovis, B. motasi, B. crassa, B. venatorum, B. divergens, B. capreoli, Theileria ovis, and T. annulata. To determine the sensitivity of the method, blood infected with 2% parasitemia of B. aktasi was diluted to 10-fold serial dilutions. The method specifically amplified a 438 bp fragment of B. aktasi DNA, but did not demonstrate cross-amplification with the other hemoparasites tested. The sensitivity assay indicated that this PCR method was able to detect infection at a dilution of 10-8 of 2% parasitemia (0.074 parasites/200 µL). Ninety-seven blood samples collected from goats were used to analyze for B. aktasi, and the infection was detected in 18.5% of the goats. Additionally, the method was also applied to 44 field DNA samples that were detected to be positive for B. aktasi by reverse line blotting (RLB), and showed 84.1% agreement. The findings revealed that newly developed semi-nested PCR can detect B. aktasi infections in goats with high sensitivity and specificity.

Sheep Displayed No Clinical and Parasitological Signs upon Experimental Infection with Babesia aktasi

Our survey in the Mediterranean region of Türkiye revealed high prevalence of Babesia aktasi in goats, while no molecular evidence of the parasite was found in sheep grazing in the same pasture. We hypothesized that the parasite may not be infectious to sheep. To test this hypothesis, the present study was designed to evaluate the susceptibility of Akkaraman sheep breed to B. aktasi infection. Fifteen mL of fresh blood infected with B. aktasi was injected into immune-suppressed lambs (n = 5). The recipient lambs were monitored daily for clinical signs of babesiosis over 30 days, and blood was collected for microscopic and molecular diagnostic evaluation. The lambs did not display clinical and parasitological signs of babesiosis. Two out of five recipient lambs were nested PCR-negative for B. aktasi over 30 days post infection. Out of the remaining three lambs, two were PCR positive on the first day, and one recipient was positive until the fourth day post infection. DNA sequencing confirmed that the PCR positivity in the recipient lambs originated from the inoculum. These findings revealed that immune-suppressed sheep do not appear to be susceptible to infection with B. aktasi that is lethal to immune-suppressed indigenous goats.

Incompetence of Vector Capacity of Rhipicephalus bursa to Transmit Babesia aktasi following Feeding on Clinically Infected Goat with High Level of Parasitemia

A recent molecular survey revealed a high prevalence of Babesia aktasi in indigenous goats from the Mediterranean region of Türkiye, coinciding with heavy Rhipicephalus bursa infestations. This geographical overlap has raised the possibility that R. bursa may serve as a vector for the parasite. To evaluate the potential of R. bursa to serve as a vector for the parasite, an experimental study was conducted in indigenous goats. An immune-suppressed donor goat was intravenously injected with 15 mL of the cryopreserved B. aktasi stabilate, resulting in severe clinical babesiosis and parasitemia. Subsequently, R. bursa larvae and adults derived from Babesia-free laboratory colonies were allowed to feed on the infected donor goat. After oviposition, engorged female carcasses, representative engorged nymphs, unfed larvae, and adult pools were used for DNA extraction and PCR analysis. No PCR positivity was detected in any of the DNA samples, except for those with engorged female carcasses and nymphs. Three immune-suppressed recipient goats were infested with the unfed immature and mature ticks consuming the blood of a donor infected with B. aktasi. No clinical or parasitological findings were encountered in the recipient for 40 days post-infestation. These findings indicated that R. bursa was not a competent vector for B. aktasi.

Identification, molecular characterization and risk factors of Theileria infection among sheep: a first comprehensive report from North India

The present study was aimed at the identification, molecular characterization, and risk factor assessment of Theileria infection among sheep of Haryana province, north India. A total of 402 blood samples were collected from three different climatic zones of Haryana from March 2020 to September 2021. Light microscopy of blood smears revealed Theileria spp. infection in 47.26% (n = 190), while 60.94% (n = 245) of blood samples were positive using nested PCR. Extensive molecular characterization of Theileria infection using four pairs of species-specific primers indicated the dominance of T. ovis (29.1%) followed by T. lestoquardi (12.69%), T. luwenshuni (5.97%) and T. annulata (1.49%). Mixed infection was detected in 11.69% of cases. Bidirectional sequencing and phylogeny further confirmed the presence of these four Theileria spp. in the investigated area under study. Hematology indicated a significant (p < 0.01) reduction in various haematological indices of animals infected with T. luwenshuni and T. lestoquardi compared to the healthy control group. Risk factors like age, sex, and zone were significantly associated with Theileria infection in sheep. The present investigation depicts the first comprehensive molecular report of ovine Theileria spp., which warrants further study to develop suitable control strategies against these haemoparasitic infections.

Molecular detection of Babesia and Theileria species/genotypes in sheep and ixodid ticks in Erzurum, Northeastern Turkey: First report of Babesia canis in sheep

Piroplasmosis is a tick-borne protozoan disease caused by Babesia and Theileria species in ruminants. This study sought to determine the presence and prevalence of the agents causing piroplasmosis among sheep in Erzurum province, Turkey. It also sought to identify the tick species infesting the sheep and investigate the possible role of the ticks in the transmission of piroplasmosis. A total of 1621 blood samples and 1696 ixodid ticks from infested sheep were collected. Each blood sample and 115 tick pools were subjected to PCR assay. A total of 307 blood samples were found to be positive for Babesia spp. and Theileria spp. according to molecular analysis. The sequence analysis was revealed the presence of B. ovis (0.4%), B. crassa (0.4%), B. canis (0.4%), T. ovis (69.3%), Theileria sp. (26.6%), and Theileria sp. OT3 (2.9%) in 244 samples. The collected ticks were identified as D. marginatus (62.5%), Hae. parva (36.2%), Hae. punctata (1.1%), Rh. turanicus (0.1%), and H. marginatum (0.1%). The molecular analysis of the adult tick samples revealed T. ovis and T. annulata positivity in the D. marginatus pools, B. crassa and T. ovis positivity in the Hae. parva pools, and T. ovis positivity in the Hae. punctata pools. These results provide up-to-date data concerning tick-borne protozoan diseases of sheep and tick species infesting sheep in the region. The sheep breeding industry is an important livelihood for the region so it is essential to perform repeated studies on these pathogens in order to prevent disruptions to animal husbandry.

Small Ruminant Piroplasmosis: High Prevalence of Babesia aktasi n. sp. in Goats in Türkiye

Small ruminant piroplasmosis is the hemoparasitic infection of sheep and goats caused by Babesia and Theileria species responsible for clinical infections with high mortality outcomes. The disease is transmitted by ixodid ticks and prevalent in the tropical and subtropical regions of the world, including Türkiye. A prevalence survey, using molecular methods, is conducted in this study to determine the frequency of newly defined Babesia aktasi n. sp. and other tick-borne piroplasm species in small ruminants in Turkiye. A total of 640 blood samples from sheep (n = 137) and goats (n = 503) were analyzed by nested PCR-based reverse line blot (RLB) hybridization. The results show that 32.3% (207/640) of apparently healthy, small ruminants are infected with three Theileria and two Babesia species. Babesia aktasi n. sp. was the most prevalent species in goats, with 22.5% of samples being positive, followed by B. ovis (4%), T. ovis (2.8%), T. annulata (2.6%), and Theileria sp. (0.6%). None of the sheep samples were positive for Babesia aktasi n. sp.; however, 51.8% were infected with T. ovis. In conclusion, the findings reveal that B. aktasi n. sp. is highly prevalent in goats, but absent in sheep. In future studies, experimental infections will determine whether B. aktasi n. sp. is infectious to sheep, as well as its pathogenicity in small ruminants.

The Scenario of Ticks and Tick-Borne Pathogens of Sheep on a Mediterranean Island

Ticks and transmitted pathogens constitute a major concern for livestock health/welfare and productivity for the Mediterranean region, often posing an important zoonotic threat. The aim of this study was to investigate the presence, infection intensity, and seasonality of ticks and tick-borne pathogens on the island of Lesvos in Greece, which was selected as a potential hotspot for their circulation. To this end, 101 sheep farms were visited over a tick activity season, and ticks, blood samples, and questionnaire data were collected. Ticks were identified by species, and DNA from both ticks and blood samples was further investigated using the polymerase chain reaction–reverse line blot (PCR–RLB) technique. In 72.3% of the farms, sheep were found to be infected by 9 ixodid species, with Rhipicephalus turanicus being the most common during the spring/early summer period. As regards tick-borne pathogens (TBPs), 84.9% of the animals were found to be infected with at least one pathogen, the most common being genera of Anaplasma and Theileria, alone or in co-infections. To further characterize the Anaplasma species found, selected samples were sequenced, revealing isolates of A. ovis, A. capra, A. marginale, and A. phagocytophilum. Of the 169 female R. turanicus ticks analyzed by PCR–RLB, 89.9% were harboring at least one TBP belonging to the genera Anaplasma, Ehrlichia, Babesia, Theileria, or Rickettsia. Overall, the data presented in this study revealed a high burden of ticks and TBPs in sheep, including zoonotic species, stressing the need for applying effective monitoring and control programs using a more holistic One Health approach.

Identification of Theileria spp. and investigation of hematological profiles of their infections in goats in Hainan Island, China

Theileria spp. are a group of parasites primarily transmitted by ticks and can pose a significant threat to domestic and wild animals globally. The main objective of this study was to understand the epidemiology of Theileria spp. in goats of Hainan Island/province, which is the only tropical region of China, and to study their hematological profiles in naturally infected goats. A total of 464 blood samples were collected from randomly selected local adult goats (Capra hircus, local domestic breed with black hair), from six cities and eight counties of Hainan, from November 2017 to October 2020. Blood smear microscopy of the sample and a nested polymerase chain reaction (nPCR) targeting the 18S rRNA gene combined with DNA sequencing were used to detect piroplasm infections in goats. Data analysis of the obtained sequences revealed that all the sequences were highly similar to the Theileria luwenshuni 18S rRNA gene sequence from the database. This result is consistent with the microscopic examination. In the hematological test, hematocrit, mean corpuscular volume, and mean corpuscular hemoglobin of the goats naturally infected with T. luwenshuni significantly increased, while mean corpuscular hemoglobin concentration and red blood cell distribution width (RDW) were significantly decreased. Results showed that T. luwenshuni could cause macrocytic, hypochromic anemia in goats. This study provides reliable and comprehensive information about the epidemiology of the parasite infections and hematological profile of the infected goats in Hainan, which encourages further investigations to develop practical control strategies for Theileria spp. infections in tropical areas.

Infection by haemopathogens and tick infestation of sheep during summer season in Constantine region, Northeast Algeria

A study on tick infestation of 43 sheep with clinical symptoms of piroplasmosis and anaplasmosis was carried out during summer seasons of 2016 and 2017 in 34 sheep flocks from Beni Hamidene locality, district of Constantine, Northeast Algeria. Only animals with clinical symptoms of piroplasmosis and/or anaplasmosis were checked for tick infestation. Among the 43 examined sheep, 58 ± 15% were infested by ticks. A total of 185 adult ticks (100 males and 85 females) were collected from the 25 sheep. Two tick genera, Rhipicephalus and Hyalomma consisting of four species were collected, Rhipicephalus bursa was the most frequent tick (164/185; 88.6 ± 4.6%), followed by Rhipicephalus sanguineus sensu lato (16/185; 8.6 ± 4%), Rhipicephalus (Boophilus) annulatus (4/185; 2.2 ± 2.1%) and Hyalomma scupense (1/185; 0.5 ± 1%). Mean overall tick infestation intensity was 7.4. Mixed infestations with two tick species were found in 10 sheep (23.3 ± 12.6%). All farmers (34/34) used ivermectin, and only 11% of them used acaricide to control ticks. The majority of R. bursa ticks (87/185; 45 ± 7%) were located on the ears 37/185; 20 ± 6%) and the testicles (50/185; 27 ± 6%). Giemsa-stained blood smears examination showed the presence of three haemopathogens: Anaplasma spp. (19/43; 44 ± 15%); Babesia spp. (6/43; 14 ± 10%) and Theileria spp. (1/43; 2 ± 4%). These results showed the presence of several low infestation burdens by ticks transmitting three haemopathogens.

Molecular prevalence, characterization and associated risk factors of Anaplasma spp. and Theileria spp. in small ruminants in Northern Pakistan

This study was conducted in four districts (Malakand, Swat, Bajaur and Shangla) of Northern Pakistan to investigate the prevalence, associated risk factors and phylogenetic analyses of Theileria and Anaplasma species in small ruminants. A total of 800 blood samples, 200 from each district, were collected from apparently healthy animals. PCR assays were performed using generic primers for Anaplasma spp. and Theileria spp. as well as species specific primers for A. ovis and T. ovis. Overall infection prevalence was 361/800 (45.1%). Theileria spp. infection prevalence (187/800, 23.3%) was higher than Anaplasma spp. (174/800, 21.7%). Amplified partial 18S rRNA genes were sequenced and enrolled animals were found to be infected by T. ovis (115/800, 14.3%), and at least two more Theileria species (72/800, 9%) were present (T. lestoquardi and T. annulata). All blood samples that were found to be positive for Anaplasma spp. were also positive for A. ovis. Infection prevalence was higher in sheep (227/361, 28.3%) compared to goats (134/361, 16.6%) (p < 0.005). Univariable analysis of risk factors showed that host, age, grazing system and acaricide treatment were significant determinants (p < 0.05) for both Theileria and Anaplasma infections. Multivariable analysis revealed that host, sex, age, tick infestation and grazing system were significant risk factors (p < 0.005) for both pathogens. Phylogenetic analysis revealed variants among the A. ovis and T. annulata samples analysed, indicating that different genotypes are circulating in the field while T. ovis presented the same genotype for the samples analysed.

Molecular Detection and Assessment of Risk Factors for Tick-Borne Diseases in Sheep and Goats from Turkey

BACKGROUND

Tick-borne diseases mainly, theileriosis, babesiosis and anaplasmosis cause significant economic losses in livestock globally, including Turkey. The tick-borne pathogens of small ruminants in Turkey have been studied widely but information on molecular characterization and disease occurrence is still limited.

METHODS

In this study, both microscopy and molecular detection and characterization for Theileria spp. Babesia ovis, Anaplasma ovis and Anaplasma phagocytophilum was conducted. A total of 133 blood samples of tick-infested small ruminants (105 sheep and 28 goats) were collected from Turkey: half of the animals had clinical signs of tick-borne disease infections.

RESULTS

Using PCR assays and microscopy, 90.2% and 45.1% of the samples were positive for at least one pathogen, respectively. Overall, the infection rates of A. phagocytophilum, B. ovis, A. ovis, Theileria spp. were 66.7%, 62.4%, 46.6% and 7.0%, respectively. Fifty-nine of the 133 (44.4%) samples were co-infected with two or more pathogens. Sex, season and B. ovis positivity were significant risk factors for occurrence of clinical disease. Sequence and phylogenetic analysis based on B. ovis 18S small subunit rRNA, A. ovis major surface protein 4, Theileria spp. 18S rRNA and A. phagocytophilum 16S rRNA genes showed that the isolates in this study clustered together in well-supported clades with those previously collected from Turkey and other countries.

CONCLUSIONS

The study shows B. ovis as the most significant pathogen associated with clinical and fatal cases in small ruminants from Turkey. Female sex and summer season are associated with increased risk of the disease. This study shows high infection rates with the pathogens among small ruminants including A. phagocytophilum which has veterinary and public health importance.

Molecular Detection of Theileria ovis and Theleiria equi in Livestock from Palestine

Theileria and Babesia are intracellular protozoan parasites infecting a wide range of animals. In Palestine, there is limited information on the prevalence of Theileria and Babesia spp. in livestock. We used PCR of the 18S ribosomal RNA gene followed by DNA sequencing to detect and identify parasite DNA in blood samples from sheep (n = 49), goats (n = 48), horses (n = 40), camels (n = 34), donkeys (n = 28) and mules (n = 2) from four districts of Palestine. DNA of T. ovis and T. equi was detected in 19 and 2 ovine blood samples, respectively. None of the camels, donkeys, and goats were positive for T. ovis. Sheep had a significantly higher rate of infection than other animals (P < 0.05). Theileria ovis is highly prevalent in sheep, while T. equi DNA was detected in a small proportion of the equids in Palestine.

First molecular survey of piroplasm species in cattle from Kyrgyzstan

Bovine piroplasmosis is a tick-borne disease caused by apicomplexan hemoparasites of the genera Theileria and Babesia. This study was carried out to assess the presence and frequency of piroplasm parasites in apparently healthy cattle in Kyrgyzstan. A total of 454 blood samples were collected from animals of various ages in eight villages located in the Chu valley and around the Lake Issyk Kul. The hypervariable V4 region of the 18S ribosomal RNA (rRNA) gene was amplified with a set of primers specific targeting members of the genera Theileria and Babesia. Amplified PCR products were hybridized onto a membrane to which generic and species-specific oligonucleotide probes were covalently linked. The results revealed the presence of three piroplasm species (Theileria orientalis, Babesia major, Theileria annulata). Theileria orientalis was the most prevalent species (32.8%; CI 28.5-37.3). Babesia major was the only species of Babesia found in any of the samples (1.3%; CI 0.5-2.8). The co-existence of Theileria annulata and T. orientalis was detected in nine animals (1.9%; CI 0.9-3.7). BLAST search revealed that the Theileria sequences shared 100% identity with the recently reported sequences for T. buffeli and T. annulata. The sequence of B. major was also 100% identical to an existing B. major sequence. This molecular survey provides important epidemiological data for control of bovine piroplasmosis caused by T. orientalis, B. major, and T. annulata in Kyrgyzstan.

Molecular Characterization and Phylogenetic Analysis of Theileria spp. and Babesia spp. Isolated from Various Ticks in Southeastern and Northwestern Regions of Iran

INTRODUCTION

Piroplasms are hemoprotozoa comprising heterogeneous tick-borne parasites, which are differentiated into three genera, namely Babesia, Theileria, and Cytauxzoon. The aim of this study was to determine the prevalence, molecular identification, and phylogenetic relationship of both Theileria spp. and Babesia spp. in tick species isolated from different domestic animals from two different geographical locations of Iran.

MATERIALS AND METHODS

A total of 930 ticks collected from goats, sheep, and cattle were examined for the presence of Theileria spp. and Babesia spp. using PCR targeting 18S rRNA gene followed by sequencing. Sequence analysis was performed based on the data published in the GenBank on Theileria spp. and Babesia spp. isolates using bioinformatic tools, such as the standard nucleotide BLAST.

RESULTS

A 390 or 430 base pair fragment of 18S rRNA gene of Theileria and Babesia species was successfully amplified in 17.2% of the examined ticks (16of 93). Genome of Theileria or Babesia species was detected in 4 ticks collected in Heris, including 3 Dermacentor marginatus and 1 Rhipicephalus sanguineus, and also in 12 ticks collected in Chabahar, including 10 R. sanguineus and 2 D. marginatus. Partial analysis of 18S rRNA gene sequence of the four D. marginatus, collected from goats and sheep in Heris, showed that they were infected with Theileria spp. that were 95-97% identical to Iranian Theileria ovis present in the GenBank database (GenBank acc. no. KP019206.1). While the five R. sanguineus, collected from sheep and goats in Chabahar, were infected with Babesia spp. that were 91-97% identical to Iranian Babesia ovis present in the GenBank database (GenBank acc. no. AY362829.1: KT587794.1).

CONCLUSION

The prevalence of Babesia and Theileria is different in southeastern and northwestern parts of Iran, with higher prevalence of babesiosis in the southeastern region and that of theileriosis in the northwestern region. Sequence analysis of 18S rRNA gene revealed that T. ovis and B. ovis are genetically polymorphic in these regions.

Semi-nested polymerase chain reaction-based detection of Babesia spp. in small ruminants from Northwest of Iran

Aim:

The present study aimed to detect Babesia ovis and Babesia motasi in the blood samples of sheep and goats from Northwest of Iran by the semi-nested polymerase chain reaction (PCR) technique.

Materials and Methods:

A total of 166 whole blood samples (including 123 sheep and 43 goats) were collected. In the first stage, the PCR was performed to amplify a piece of 18S rRNA gene of Babesia and Theileria genera. Then, semi-nested PCR was carried out on all PCR products to differentiate B. ovis and B. motasi.

Results:

The PCR indicated that totally, 19 (11.44%) out of 166 samples were positive for Babesia or Theileria spp. The semi-nested PCR showed that 38 samples (22.89%) were positive only for B. ovis. No significant association was found between the infection rate of B. ovis and age, gender and species of animals.

Conclusion:

In the present study, there was no evidence for B. motasi infection in small ruminants from Northwest of Iran. Therefore, B. ovis was the main causative agent of ovine Babesiosis in this region.

Studies on theileriosis in goats from Karnataka, South India

A study was conducted to determine the prevalence of theileriosis in goats from southern districts of Karnataka. Out of 47 goat blood samples examined by microscopy, 68.08% (32/47) were positive for Theileria spp. The parasitemia ranged from 1.0 to 1.8 and 0.1-0.9% in clinical and carrier animals respectively. Out of 325 ticks collected from goats, 92.6 (301) and 7.38 (24)% of the ticks were found to be Haemaphysalis and Rhipicephalus respectively. Hemaphysalis kutchensis (90.15%) was found to be the predominant species followed by R. haemaphysaloides (6.7%), H. intermedia (1.84%), H. bispinosa (0.61%) and R. sanguineus (0.61%). The present study indicated that caprine theileriosis is an endemic disease in Karnataka and suggested that Haemaphysalis and Rhipicephalus ticks may play a role in transmission of the disease.

A survey of canine haemoprotozoan parasites from Turkey, including molecular evidence of an unnamed Babesia

Canine tick-borne apicomplexan parasites have emerged in recent years, showing a wider geographic distribution and increased global prevalence. A reverse line blot assay was performed on 219 blood samples collected from domestic dogs for simultaneous detection of all named canine piroplasm species as well as Hepatozoon canis. Ten samples hybridized to the Theileria/Babesia and Babesia catch all probes but did not hybridize to any species-specific probe tested, suggesting the presence of an unrecognized Babesia species or genotype. Sequencing results showed 91.5%, 91.9%, 92.4%, 92.4%, and 89.2% similarity to B. canis, B. vogeli, B. rossi, B. gibsoni, and B. conradae, respectively. The highest homology (98.1-98.5%) observed was with unnamed Babesia sp. isolates (Ludhiana and Malbazar) described in dogs, Babesia sp. of buffalo origin, Babesia sp. Kashi 2, and Babesia orientalis, along with Babesia occultans of cattle origin. The partial cox1 sequence indicated that this isolate was most similar to Babesia sp. 1 HG-2012, with an identity of 86.5%. The survey revealed high prevalence of haemoprotozoans in domestic dogs (57.5%, CI 50.7-64.2), with Hepatozoon canis the most prevalent (54.3%, CI 47.5-61.117%), followed by Babesia sp. (4.6%, CI 2.2-8.2), B. vogeli (1.4%; CI 0.3-3.9), and B. canis (0.4%, CI 0-2.5). Combined infection of Hepatozoon canis and Babesia sp. was detected in five (2.3%, CI 0.7-5.2) samples and of H. canis and B. vogeli in two (0.9%, CI 0.1-3.2) dogs. The study contributes insight into the distribution and phylogenetic diversity of canine piroplasms in Turkey.

Molecular surveillance of Theileria parasites of livestock in Oman

BACKGROUND

Theileriosis is one of the most prevalent infectious diseases of livestock in the Arabian Peninsula, and causes high rates of mortality and morbidity in sheep and cattle. However, there is a paucity of information on the distribution of Theileria spp. over the whole region and their impact on different hosts. The present study carried out a country-wide molecular survey for Theileria spp. of livestock in Oman across four governorates. The aim of the survey was to define the prevalence of Theileria spp. in cattle, sheep and goats, highlight risk factors for infection and identify the main tick species involved in parasite transmission.

MATERIAL AND METHODS

A total of 2020 animals were examined in the survey consisting of sheep [n=592], goats [n=981] and cattle [n=447]. All three species were raised and co-grazed on the same farms. Theileria parasites were detected using PCR-RFLP and RLB of the 18S rRNA gene. Cloning and sequencing of the 18S rRNA was carried out on 11 T. lestoquardi isolates from Ash-Sharqiyah, and Ad-Dhahira governorates, and phylogenetic relationships were inferred using additional sequences of T. lestoquardi, T. annulata and T. ovis available in GenBank.

RESULTS

Theileria spp. prevalence was 72.3%, 36.7% and 2.7% among cattle, sheep and goats, respectively. Strong similarity in results was obtained using RLB and PCR-RFLP for detection of Theileria spp. however, RLB detected a higher rate of mixed infection than PCR-RFPL (P<0.001). Theileria annulata was the only parasite detected in cattle, while sheep and goats carried T. ovis, T. lestoquardi and T. annulata as well as Theileria spp. OT1. Of the four Theileria spp. detected in small ruminants, overall T. ovis was most prevalent (sheep [33.4%], goats [2.0%]), whereas T. lestoquardi was less prevalent (sheep [22.0%], goats [0.5%]). A large proportion of infected sheep (19%) carried mixed infection of T. ovis and T. lestoquardi. However, single T. lestoquardi infections (3.0%) were less prevalent than T. ovis infections (14.5%). Risk of Theileria spp. infection was significantly higher for exotic breeds, relative to native breeds, of cattle (p=0.00002) and sheep (p=0.005). Phylogenetic analysis placed T. lestoquardi in Oman in the same clade as other T. lestoquardi strains isolated from the same regional area (Iraq and Iran). The main tick species, identified on the examined animals, Hyalomma anatolicum, was widely distributed and was found in all of the surveyed governorates.

CONCLUSION

Theileria spp. are widespread in Oman with variable prevalence detected in different regions. Two economically important hosts, cattle and sheep are at high risk from virulent T. annulata and T. lestoquardi, respectively. The survey indicates extensive exposure to ticks and transmission of infection that has a significant economic impact. The higher prevalence of T. lestoquardi as mixed rather than single infection requires further investigation.

Molecular and Parasitological Survey of Ovine Piroplasmosis, Including the First Report of Theileria annulata (Apicomplexa: Theileridae) in Sheep and Goats from Turkey

Blood and tick samples were collected from 333 apparently healthy sheep and 257 goats as well as 10 sheep exhibiting clinical signs of babesiosis in Adana, Gaziantep, and Adiyaman Provinces in southern Turkey. Fully engorged female ticks were selected and maintained in an incubator until they oviposited. The tick carcasses and their egg masses were examined. Piroplasms compatible with Babesia spp. and Theileria spp. were observed in both symptomatic and asymptomatic small ruminants. Genomic DNA isolates from blood of ovine, tick samples, and egg masses were screened for piroplasms by utilizing 18S rRNA polymerase chain reaction and reverse line blotting (RLB) assays. Parasitemia ranged from 0.01% to 5.6% of erythrocytes in clinical cases. RLB showed positivity in 239 (40.5%) of the sampled apparently healthy sheep and goats and revealed the presence of three Theileria and one Babesia species. Theileria ovis was the most prevalent (35.4%), followed by Babesia ovis (5.4%), Theileria annulata (3.9%), and Theileria sp. MK (0.3%). Thirty-two small ruminants infected with T. ovis were also infected with B. ovis One animal infected with T. ovis was also infected with Theileria sp. MK. Ticks were identified as Rhipicephalus bursa, Rhipicephalus turanicus, Hyalomma excavatum, Haemaphysalis parva, and Hyalomma anatolicum Egg masses of two female R. bursa carcasses were infected with B. ovis This is the first report of theileriosis caused by T. annulata in sheep and goats in Turkey.

Molecular evidence of a new Babesia sp. in goats

In this study, a novel Babesia sp. infecting goats was detected and its phylogenetic relationship to related species was determined. A total of 200 blood samples collected from sheep (n=78) and goats (n=122) were examined in the study. The V4 hypervariable region of the 18S rRNA gene of the novel Babesia sp. was amplified by PCR and analysed using a reverse line blot hybridization assay adapted for small ruminants. Samples from seven goats hybridized to Theileria/Babesia catch-all and Babesia catch-all probes and did not hybridize to any species-specific probe tested, suggesting the presence of an unrecognized Babesia species or genotype. Sequencing results showed the isolate to clearly differ from ovine Babesia species and genotypes currently available in the GenBank database. The isolate showed 90.9%, 93.5%, and 93.4% identity to B. ovis, B. motasi, and B. crassa, respectively and 91-93% similarity to Babesia genotypes recently described in small ruminants. The highest homology (∼96-97%) observed was with Babesia odocoilei, Babesia sp. EU1, and Babesia divergens. The new isolate was provisionally designated Babesia sp. The study contributes to better insight into the distribution and phylogenetic diversity of piroplasms in small ruminants. The survey indicated a high prevalence of piroplasms in small ruminants (21.5%). Of those detected, T. ovis was the most prevalent (17%), followed by Babesia sp. (3.5%), and B. ovis (2%).

Ticks threatening lineage of Anatolian wild sheep (Ovis gmelinii anatolica) and determination of their tick-borne pathogens

We aimed to determine the ticks of the Anatolian wild sheep and to define their tick-borne pathogens while molecularly studying their relationships with those of the domestic sheep. Furthermore, another aim of this study is to investigate tick paralysis resulting in the death of the Anatolian wild sheep. Ticks and blood samples were collected from the wild sheep whilst tick samples were also collected from hares, guinea fowls, chickens, and a turkey living in the Anatolian wild sheep breeding area. While PCR amplification was carried out for the detection of Babesia spp., Theileria spp. and Anaplasma spp. in blood samples, CCHF virus was screened in the tick samples in addition to the above-mentioned pathogens. Theileria spp. was detected in blood samples of 45 wild sheep. A total of 3494 ticks were collected from 52 Anatolian wild sheep, 5 hares, 5 guinea fowls, 2 chickens, and 1 turkey whereas 98 ticks were collected from the ground. B. ovis and T. ovis were detected in tick pools (Rh. bursa and H. excavatum) that were collected from the wild sheep. The paralysis was diagnosed in both of the hind legs of the newborn lambs infested with a great number of ticks. We also report that the tick species (H. excavatum and Rh. bursa) are determined to cause tick paralysis and tick toxicosis, which are associated with mortality especially in lambs. T. ovis and B. ovis were detected and studied for the first time in Anatolian wild sheep and in their ticks. The results of phylogenetic analyses showed that T. ovis and B. ovis isolates are genetically very close to the isolates that were previously obtained from the domestic small ruminants. We show that the Anatolian wild sheep can play the role of a reservoir for T. ovis. The presence of the CCHF virus has also been clearly shown and it has been observed that this virus, which is very pathogenic for humans, is anywise circulating in the region.

Genetic diversity and molecular characterization of Babesia motasi-like in small ruminants and ixodid ticks from China

Ovine babesioses, an important tick-borne disease of sheep and goats in China, is caused by the reproduction of intraerythrocytic protozoa of the Babesia genus. Babesia motasi-like is a Babesia parasite that infects small ruminant in China, and two sub-groups of B. motasi-like can be subdivided based on differences in the rhoptry-associated-protein-1 gene. This study aimed to characterize the distribution, epidemiology and genetics of B. motasi-like in animals and ticks. A molecular investigation was carried out from 2009 to 2015 in 16 provinces in China. In total, 1081 blood samples were collected from sheep and goats originating from 27 different regions, and 778 ixodid tick samples were collected from 8 regions; the samples were tested for the presence of B. motasi-like using a specific nested PCR assay based on the rap-1b gene. The results indicated that 139 (12.9%), 91 (8.4%), 48 (4.4%) and 6 (0.7%) of the blood samples were positive for general B. motasi-like, Babesia sp. BQ1 (Lintan and Ningxian), Babesia sp. Tianzhu and Babesia sp. Hebei sub-groups, mixed infections, respectively. Among the collected 778 ixodid ticks (including Haemaphysalis longicornis, Haemaphysalis qinghaiensis, Dermacentor silvarum, Ixodes persulcatus, Rhipicephalus sanguineus and Rhipicephalus (Boophilus) microplus), the most frequently infected with Babesia were D. silvarum and I. persulcatus (35.7%), followed by H. longicornis (26.8%), H. qinghaiensis (24.8%) and R. sanguineus (9.3%). The PCR results were confirmed by DNA sequencing. The positive rates of B. motasi-like infection in ticks were found to be higher in China, compared with previous studies in other countries. B. motasi-like infections have not previously been reported in D. silvarum, I. persulcatus or R. sanguineus. The findings obtained in this study could be used for planning effective control strategies against babesiosis in China.

Molecular Detection of Theileria spp. in Livestock on Five Caribbean Islands

Theileria spp. are tick-transmitted, intracellular apicomplexan protozoan parasites infecting a wide range of animals. As there is very limited information on the prevalence of Theileria spp. in the Caribbean we used the recently described genus-specific pan-Theileria FRET-qPCR to identify infected animals in the region and a standard 18S rRNA gene PCR and sequencing to determine the species involved. We found Theileria spp. in 9% of the convenience samples of animals (n = 752) studied from five Caribbean islands. Donkeys (20.0%: 5/25) were most commonly infected, followed by sheep (17.4%, 25/144), cattle (6.8%; 22/325), goats (5.0%; 12/238), and horses (5.0%; 1/20). Six species of Theileria were identified: T. equi (donkeys, cattle, goats, and sheep), Theileria sp. OT3 (sheep and goats), Theileria sp. NG-2013a (cattle), Theileria sp. YW-2014 (donkeys), Theileria sp. B15a (goats), and Babesia vulpes or a closely related organism (sheep and goats). Only T. equi has been previously reported in the Caribbean. Our findings expand the known host ranges of Theileria spp. and the known distribution of the organisms around the world.

Molecular and Parasitological Survey of Bovine Piroplasms in the Black Sea Region, Including the First Report of Babesiosis Associated with Babesia divergens in Turkey

Clinical cases of babesiosis were evaluated, and the frequency of bovine Babesia and Theileria parasites was determined in cattle. Blood samples and thin blood smears were collected from 23 cattle exhibiting clinical signs of babesiosis. In addition, tick and blood samples were collected from 100 apparently healthy cattle cograzing from the same area. Egg masses obtained from fully engorged female ticks were included. DNA isolated from blood and tick samples was screened for Babesia and Theileria by reverse line blot assay. Piroplasms compatible with Babesia spp. were observed microscopically for symptomatic cattle as circular, oval, elongated, or pear-shaped bodies. Parasitemia ranged from 0.08 to 0.9% for Babesia bovis, 2.5 to 15.4% for Babesia bigemina, and 7.4% for Babesia divergens. Reverse line blot showed positivity in 13 (13%) of the sampled clinically normal cattle and revealed the presence of three Babesia species. Babesia bovis was the most prevalent (9/100, 9%), followed by Babesia occultans (3/100, 3%) and B. bigemina (1/100, 1%). One animal infected with B. bigemina was also infected with B. bovis. The single animal infected with B. divergens showed symptoms of babesiosis. Ticks were identified as Rhipicephalus annulatus, Rhipicephalus turanicus, and Ixodes ricinus. One female R. annulatus and its egg mass were infected with B. bigemina. Neither Theileria annulata nor Theileria buffeli/orientalis infections were observed in cattle or ticks. This is the first report of clinical babesiosis caused by B. divergens in cattle from Turkey.

A case of severe babesiosis treated successfully with exchange transfusion

Babesiosis is a zoonotic disease that may be asymptomatic or result in severe clinical conditions, with severe hemolysis, hepatic, and renal failure, in humans. Clinical symptoms depend on the species and immune status of the host. The disease is especially severe in those of advanced age, those with an immune deficiency, and the splenectomized. A severe case of babesiosis that developed in a splenectomy patient is presented here; the patient was admitted from a rural region with severe anemia and a deterioration in her general condition, with an initial diagnosis of malaria. In such situations, an exchange transfusion (ET), in addition to antimicrobial treatment, could be lifesaving.

Molecular detection and characterization of Hepatozoon spp. in dogs from the central part of Turkey

Canine hepatozoonosis is a tick-borne protozoal disease caused by Hepatozoon spp. Two species of Hepatozoon are currently known to infect dogs as Hepatozoon canis and H. americanum. Although H. canis generally causes a chronic infection with relatively mild clinical alterations compared to H. americanum, infection by H. canis can be life-threatening. The disease is widespread in USA, Africa, Europe, South America, and Asia. To determine the frequency of infection with Hepatozoon spp. in stray dogs from Central Anatolia Region of Turkey, a total of 221 blood samples collected over a three-year period were evaluated by using genus specific Polymerase Chain Reaction (PCR) designed to amplify a fragment of 666bp located in 18 S rRNA gene of Hepatozoon spp. Eight (3.61%) blood samples were positive for Hepatozoon spp. For the classification of species, all positive PCR products were purified with a PCR purification kit and sequenced. Sequencing results of eight representative amplicons indicated that 6 were 98-99% identical to the sequence of H. canis and the other 2 sequences were 95-97% identical to the sequence of Hepatozoon spp. So it was named Hepatozoon sp. MF. A phylogenetic tree was constructed from the sequences of the tick-borne agents identified previously and in this study using the neighbor-joining method. The nucleotide sequences were compared to the H. canis sequences reported in Turkey using the nucleotide Basic Local Alignment Search Tool (BLAST) program. The results of this study are significant in terms of the presence of a novel canine Hepatozoon genotype.

Molecular detection of tick-borne rickettsial and protozoan pathogens in domestic dogs from Turkey

Background

Canine tick-borne parasites have emerged in recent years, showing a wider geographic distribution and increased global prevalence. In addition to their veterinary importance, domestic dogs play an important role in the transmission cycles of some agents by acting as reservoirs and sentinels. This study investigated Babesia, Theileria, Anaplasma, and Ehrlichia species in asymptomatic dogs in ten provinces of Turkey.

Methods

DNA obtained from blood samples collected from 757 domestic dogs (243 stray, 351 shelter, 163 pet) of both sexes and various ages were evaluated using PCR and reverse line blotting (RLB) assays.

Results

Of the 757 dogs tested, 41 (5.4%) were found to be infected with one or more parasites. Ehrlichia canis (37/757, 4.9%) was the most common canine tick-borne pathogen, followed by Anaplasma platys (4/757, 0.5%). Babesia canis and Theileria annulata were each detected in 1 (0.13%) sample. Combined infection of E. canis and A. platys was detected in 2 (0.3%) samples. The prevalence of tick-borne pathogens was higher in adult dogs (6.8%) than in those under one year old (3.1%). Difference in infection rate of male and female dogs was not significant. Pet dogs had a lower prevalence of infection (1.2%) compared to stray (7.4%) and shelter dogs (6%) although the difference between stray and shelter dogs was not significant.

Conclusions

Babesia canis, T. annulata, A. platys, and E. canis species were identified at the molecular level in dogs in several provinces of Turkey, with E. canis being the most common species among tick-borne pathogens. Detailed studies should be conducted regarding the existence and prevalence of B. canis and Dermacentor reticulatus in eastern Turkey.

Molecular identification of Theileria and Babesia in ticks collected from sheep and goats in the Black Sea region of Turkey

A molecular survey was undertaken in the Black Sea region of Turkey to determine the presence of Theileria and Babesia species of medical and veterinary importance. The ticks were removed from sheep and goats, pooled according to species and locations, and analyzed by PCR-based reverse line blot (RLB) and sequencing. A total of 2241 ixodid ticks belonging to 5 genus and 12 species were collected and divided into 310 pools. Infection rates were calculated as the maximum likelihood estimation (MLE) with 95% confidence intervals (CI). Of the 310 pools tested, 46 (14.83%) were found to be infected with Theileria or Babesia species, and the overall MLE of the infection rate was calculated as 2.27% (CI 1.67-2.99). The MLE of the infection rates were calculated as 0.691% (CI 0.171-1.78) in Haemaphysalis parva, 1.47% (CI 0.081-6.37) in Rhipicephalus sanguineus, 1.84% (CI 0.101-7.87) in Ixodes ricinus, 2.86% (CI 1.68-4.48) in Rhipicephalus turanicus, 5.57% (CI 0.941-16.3) in Hyalomma marginatum, and 6.2% (CI 4.02-9.02) in Rhipicephalus bursa. Pathogens identified in ticks included Theileria ovis, Babesia ovis, Babesia bigemina, and Babesia microti. Most tick pools were infected with a single pathogen. However, five pools displayed mixed infections with T. ovis and B. ovis. This study provides the first molecular evidence for the presence of B. microti in ticks in Turkey.

Theileria infection in domestic ruminants in northern Ethiopia

Piroplasmosis caused by different tick-borne hemoprotozoan parasites of the genera Theileria and Babesia is among the most economically important infections of domestic ruminants in sub-Saharan Africa. A survey for piroplasm infection was conducted in three locations in Northern Ethiopia. Of 525 domestic ruminants surveyed, 80% of the cattle, 94% of the sheep and 2% of the goats were positive for different Theileria spp. based on PCR of blood followed by DNA sequencing. Sheep had a significantly higher rate of infection compared with cattle (P<0.0003) and both sheep and cattle had higher rates of infection compared to goats (P<0.0001). Four species of Theileria were detected in cattle: T. velifera, T. mutans, T. orientalis complex and T. annulata with infection rates of 66, 8, 4, and 2%, respectively. This is the first report of T. annulata, the cause of Tropical Theileriosis in Ethiopia. Of the two Theileria spp. detected in small ruminants, T. ovis was highly prevalent (92%) in sheep and rare in goats (1.5%) whereas T. seperata was infrequent in sheep (2%) and rare in goats (0.4%). None of the animals were positive for Babesia spp.; however, Sarcocystis capracanis and S. tenella were detected in one goat and a sheep, respectively. The widespread distribution of Theileria spp. among cattle in northern Ethiopia including the virulent T. annulata and more mildly pathogenic T. mutans and T. orientalis, and the high infection rate in sheep with the usually sub-clinical T. ovis indicate extensive exposure to ticks and transmission of piroplasms with an important economic impact.