Epidemiological survey of Theileria orientalis infection in grazing cattle in the eastern part of Hokkaido, Japan

First report of oriental theileriosis in the Intermediate Zone, Sri Lanka: Is Theileria orientalis type 7 always apathogenic?

PURPOSE

Theileriosis in cattle has a significant economic implication for dairy production globally. Thus, it is crucial to investigate the prevalence of bovine theileriosis, the causative agent and genotypes of Theileria species in dairy cattle in the Kurunegala District in the Intermediate zone, where the third largest population of dairy cattle in Sri Lanka is present and experienced a substantial reduction in the cattle population recently.

METHODS

Sixty blood samples and background data were collected from three dairy farms in Galpokuna (n = 20), Koulwewa (n = 20), and Andigama (n = 20) areas. Haematocrit was used to identify anaemia while Giemsa-stained blood smears demonstrated the presence of piroplasms. A Fisher's Exact Test (p < 0.05) compared the prevalence of infection among age groups and farms. PCRs using species-specific primers designed to amplify regions of MPSP and 18 s rRNA genes followed by sequencing of selected amplicons allowed phylogeny of the species detected.

RESULTS

All three farms had semi-intensive farming practices keeping animals in a 'closed' setup with limited movement. Theileriosis prevalence in dairy cattle was 55.0 % with no difference among the farms (Koulwewa: 65.0 %, Galpokuna: 50.0 %, Andigama: 50.0 %). One-third of the cattle (33.3 %) were anaemic based on haematocrit results but most showed mild anaemia. Anaemia was significantly higher in calves (45.0 %) than in adults (25.0 %; χ2 = 5.743; p = 0.03) tested positive for theileriosis. None of the animals showed any other signs of theileriosis. PCR revealed the presence of both T. orientalis (pathogenic or benign) and T. annulata (pathogenic). The sequencing data revealed that the T. orientalis genotype present in Kurunegala District is type 7.

CONCLUSION

This is the first report on T. orientalis and T. annulata in dairy cattle in the Intermediate zone of Sri Lanka. The type 7 of T. orientalis was more common showing severe anaemia in calves while mild anaemia or no anaemia in adults and sub-adults. In immunologically intact animals, the reported genotype of the parasite can persist asymptomatically for life, occasionally causing a relapse, particularly under stressful conditions like pregnancy, lactation, and rapid changes in environmental conditions. However, the susceptibility of calves for pathogenic and apathogenic genotypes of T. orientalis and the carrier status of asymptomatic animals needs further investigation.

Identification of novel bovine leukocyte antigen alleles and association of BoLA-DRB3.2*020:02:01 with resistance to Theileria orientalis infection in crossbred Kedah-Kelantan cattle: a pilot study

The bovine leukocyte antigen (BoLA) gene is a significant genetic part of the immune system and has been used as a disease marker in cattle. In this study, we detected Theileria orientalis, T. sinensis, Anaplasma marginale, Anaplasma platys, Candidatus Mycoplasma haemobos and Trypanosoma evansi by PCR amplification and sequencing of the amplicons. The allelic association of the BoLA-DRB3.2 gene with blood pathogen disease resistance and susceptibility in 87 Kedah-Kelantan x Brahman (KKB) and 38 Bali cattle was determined by Fisher's exact test and Cochran Mantel Haenszel (CMH) correction test. Sequence-based typing of the BoLA-DRB3.2 gene identified 43 alleles (27 previously reported alleles and 16 novel alleles) across the two cattle breeds. Alignment analysis of the 16 novel alleles revealed 90.7-95.8% and 85-92% nucleotide and amino acid identities, with the reference allele, BoLA-DRB3*016:01 cDNA clone NR-1. BoLA-DRB3*009:02 (25.6%) and BoLA-DRB3*036:01 (36%) were the most frequent alleles in KKB and Bali cattle, respectively. In KKB cattle, BoLA-DRB3*020:02:01 was significantly associated with resistance to T. orientalis whereas *007:01 and *009:02 were significantly associated with resistance to C. Mycoplasma haemobos. Also, DRB3*017:01 was associated with susceptibility to T. orientalis in KKB cattle. In the Bali cattle, BoLA-DRB3*015:01 was found to be a genetic marker of susceptibility to C. Mycoplasma haemobos infection. Therefore, this study identified BoLA-DRB3.2 alleles associated with resistance and susceptibility to T. orientalis infection in KKB cattle and susceptibility to C. Mycoplasma haemobos infection in Bali cattle for the first time. Therefore, this study suggests that these BoLA-DRB3 resistance alleles could be used as candidate markers for selection, whereas susceptibility alleles could be used as candidate markers for culling in the beef industry.

Identification of hemolytic anemia in Korean indigenous cattle with a criteria value of reticulocyte count, indirect bilirubin, and L-lactate concentration

Bovine hemolytic anemia has a negative impact on animal welfare and productivity due to its associated clinical symptoms. Hemolysis is generally known to cause reticulocytosis, increased indirect bilirubin, decreased concentration of haptoglobin, and increased lactate dehydrogenase. Additionally, tissue hypoperfusion due to concomitant anemia increases blood lactate concentration. However, few studies have reported the correlation between these indicators and hemolytic anemia in cattle. We expected that alterations in hematological and biochemical parameters could identify cattle with hemolytic anemia. Therefore, in addition to reporting differences in indicators according to hemolytic anemia, this study aimed to derive indicators and set criteria for identification of bovine hemolytic anemia. In cattle with hemolytic anemia, reticulocytosis, increased indirect bilirubin, and increased L-lactate were observed, and the correlation of these indicators with hematocrit (HCT) was confirmed. And since HCT alone has limitations in identifying hemolytic anemia, we suggest additional criteria to identify hemolytic anemia in cattle.

First molecular survey of tick-borne protozoan and bacterial pathogens in the questing tick population in Bangladesh

Questing ticks carry various tick-borne pathogens (TBPs) that are responsible for causing tick-borne diseases (TBDs) in humans and animals around the globe, especially in the tropics and sub-tropics. Information on the distribution of ticks and TBPs in a specific geography is crucial for the formulation of mitigation measures against TBDs. Therefore, this study aimed to survey the TBPs in the questing tick population in Bangladesh. A total of 2748 questing hard ticks were collected from the pastures in Sylhet, Bandarban, Sirajganj, Dhaka, and Mymensingh districts through the flagging method. After morphological identification, the ticks were grouped into 142 pools based on their species, sexes, life stages, and collection sites. The genomic DNA extracted from tick specimens was screened for 14 pathogens, namely Babesia bigemina (AMA-1), Babesia bovis (RAP-1), Babesia naoakii (AMA-1), Babesia ovis (18S rRNA), Theileria luwenshuni (18S rRNA), Theileria annulata (Tams-1), Theileria orientalis (MPSP), Anaplasma marginale (groEL), Anaplasma phagocytophilum (16S rRNA), Anaplasma bovis (16S rRNA), Anaplasma platys (16S rRNA), Ehrlichia spp. (16S rRNA), Rickettsia spp. (gltA), and Borrelia (Bo.) spp. (flagellin B) using genus and species-specific polymerase chain reaction (PCR) assays. The prevalence of the detected pathogens was calculated using the maximum likelihood method (MLE) with 95 % confidence interval (CI). Among 2748 ixodid ticks, 2332 (84.86 %) and 416 (15.14 %) were identified as Haemaphysalis bispinosa and Rhipicephalus microplus, respectively. Haemaphysalis bispinosa was found to carry all the seven detected pathogens, while larvae of R. microplus were found to carry only Bo. theileri. Among the TBPs, the highest detection rate was observed in A. bovis (20/142 pools, 0.81 %, CI: 0.51-1.20), followed by T. orientalis (19/142 pools, 0.72 %, CI: 0.44-1.09), T. luwenshuni (9/142 pools, 0.34 %, CI: 0.16-0.62), B. ovis (4/142 pools, 0.15 %, CI: 0.05 - 0.34) and Bo. theileri (4/142 pools, 0.15 %, CI: 0.05-0.34), Ehrlichia ewingii (3/142 pools, 0.11 %, CI: 0.03-0.29), and Babesia bigemina (1/142, 0.04 %, CI: 0.00 - 0.16). This study reports the existence of T. luwenshuni, E. ewingii, and Bo. theileri in Bangladesh for the first time. The novel findings of this study are the foremost documentation of transovarian transmission of B. bigemina and E. ewingii in H. bispinosa and also provide primary molecular evidence on the presence of E. ewingii and Bo. theileri in H. bispinosa. Therefore, this study may shed light on the circulating TBPs in ticks in the natural environment and thereby advocate awareness among physicians and veterinarians to control and prevent TBDs in Bangladesh.

Molecular detection and phylogenetic analysis of tick-borne pathogens in cattle from southern Malawi

INTRODUCTION

Tick-borne diseases (TBDs) pose a major hindrance to livestock production in countries with limited resources. Effective prevention and management of TBDs require a thorough understanding of disease vectors and pathogens. However, there is limited information on studies of bovine tick-borne pathogens (TBPs) using molecular methods in Malawi. This study aimed to detect TBPs of cattle populations in southern Malawi, which has the largest cattle population in the country.

METHODOLOGY

A total of 220 blood samples from apparently healthy cattle were collected in six districts, and were screened for selected TBPs using polymerase chain reaction (PCR).

RESULTS

The overall detection rate of TBPs was 72.3%. Among the detected pathogens, Babesia bigemina had the highest detection rate (34.5%), followed by Anaplasma marginale (23.2%), Anaplasma phagocytophilum (22.3%), Theileria taurotragi (22.3%), Theileria parva (15.5%), Anaplasma bovis (9.6%), Babesia bovis (7.3%), Theileria mutans (4.1%), and Babesia naoakii (2.7%). Among the positive samples, 64.2% were found to be co-infected with two or more TBPs, with the highest number of seven pathogens detected in a single sample. The study documents the existence of A. phagocytophilum, B. bovis, and B. naoakii in Malawian cattle for the first time.

CONCLUSION

The findings herein demonstrate a significant burden of TBPs on cattle in Malawi, which gives a challenge in combating TBDs. The high TBP burden, along with the high co-infection frequencies in Malawian cattle necessitates the urgency to implement effective control strategies to enhance cattle production in the country.

Transient efficacy of buparvaquone against the US isolate of Theileria orientalis Ikeda genotype in sub-clinically infected cattle

Introduction

Theileria orientalis, an economically significant tick-borne hemoparasite, infects cattle globally. The T. orientalis Ikeda genotype, transmitted by Haemaphysalis longicornis ticks, is associated with clinical manifestations characterized by anemia, abortions, and mortality, although subclinical infections prevail. Despite the common occurrence of subclinical infections, therapeutic interventions targeting T. orientalis Ikeda in such cases are currently lacking, impeding effective parasite control measures. To address this critical knowledge gap, we assessed the efficacy of buparvaquone (BPQ) in eliminating the T. orientalis Ikeda, US isolate, in sub-clinically infected cattle.

Methods

Twelve sub-clinically infected calves, identified by the presence of T. orientalis in peripheral blood alongside the absence of fever and anemia, were enrolled in the study. Six calves received two treatments of the BPQ label dose (2.5 mg/kg) at a 48-h interval, while additional three calves received the drug at a dosage of 6 mg/kg following the same regimen. Three untreated calves served as controls.

Results and discussion

Endpoint and quantitative PCR analyses revealed that BPQ exerted a transient effect on T. orientalis parasitemia. Parasites remained undetectable in peripheral blood until weeks 4 and 11 post-treatment in animals administered 2.5 mg/kg and 6 mg/kg of BPQ, respectively. Intriguingly, following recrudescence, administering 6 mg/kg to animals previously treated with 2.5 mg/kg did not result in a reduction in parasite load. Pharmacokinetic analysis data suggested that escalating the dosage led to a less than proportional increase in serum concentrations of BPQ. Moreover, a significant yet reversible decrease (p < 0.05) in blood urea nitrogen was observed in animals treated with the drug, irrespective of the dosage. Despite parasitemia relapse, animals treated with 6 mg/kg BPQ exhibited a noteworthy decrease (p < 0.05) in IgG levels specific to the T. orientalis major piroplasm surface protein compared to controls and animals treated with 2.5 mg/kg of the drug.

Conclusion

BPQ did not demonstrate efficacy in clearing subclinical T. orientalis Ikeda infection. Future investigations are warranted to explore innovative therapeutic modalities that, in synergy with vaccines and diagnostic assays, can facilitate the development of comprehensive programs aimed at controlling and eradicating this parasite.

Wide bovine tick-borne pathogen spectrum: Predominancy of Theileria annulata and the first molecular detection of Ehrlichia minasensis in Turkey

Vector-borne diseases indulge in severe economic losses in the livestock industry by adversely affecting cattle breeding in tropical and subtropical zone countries, including Turkey, encompassing a wide land area representing diverse climatic conditions. This study aimed to investigate significant bovine tick-borne piroplasm, rickettsia, and some other bacterial agents by genus- or species-specific PCR and nested PCR techniques in Turkey. A total of 210 cattle blood samples were collected from sixteen provinces in different geographical regions of Turkey. PCR analyses were performed targeting the detection of Babesia/Theileria/Hepatozoon sp. 18S rRNA, Babesia/Theileria sp. 18S rRNA (V4), B. bigemina RAP-1a, B. bovis SBP-4, B. ovata AMA-1, B. naoaki AMA-1, T. annulata Tams-1, T. orientalis MPSP, T. mutans 18S rRNA, Anaplasma/Ehrlichia sp. 16S rRNA, A. marginale MSP4, A. bovis 16S rRNA, A. phagocytophilum 16S rRNA, A. capra 16S rRNA, E. ruminantium pSC20, Mycoplasma sp. 16S rRNA, and Coxiella burnetii 16S rRNA genes. Overall, 133 (63.3%) cattle were found to be infected with at least one of the following protozoan or bacterial pathogens; B. bovis, B. bigemina, B. occultans, T. annulata, T. orientalis, A. marginale, A. phagocytophilum, and Mycoplasma sp. The total prevalence of pathogens was determined as follows; 0.5% B. bovis, 0.5% B. bigemina, 1.4% B. occultans, 41.0% T. annulata, 1.4% T. orientalis, 10.5% A. marginale, 13.8% A. phagocytophilum, 0.5% A. bovis, 2.9% Uncultured Anaplasma sp., 0.5% E. minasensis, 0.5% Uncultured Ehrlichia sp., and 23.3% Mycoplasma sp. Moreover, large part of the total infection (n:133) was composed of single infections (63.9%); however, double (24.8%), triple (7.5%), quadruple (2.3%), and quintuple (1.5%) co-infections were also encountered. In addition to some bovine pathogens such as B. occultans, T. orientalis, A. bovis, M. wenyonii, and Candidatus Mycoplasma haemobos, which were rarely reported in Turkey, sequencing and phylogenetic analysis revealed the first detection of Uncultured Ehrlichia sp. (0.5%), and E. minasensis (0.5%) with 100% nucleotide sequence identities. The study also indicates that the spectrum of pathogens harbored by Turkish cattle is quite wide, and these pathogens cause multiple co-infections with various combinations, and T. annulata stands out as the primary bovine pathogen among them.

First report of Ikeda genotype of Theileria orientalis in Mithun (Bos frontalis) from northeastern hilly region of India

Oriental theileriosis caused by Theileria orientalis, previously considered a benign disease, is posing a significant threat to the livestock industry across the globe. To elucidate the prevalence of Theileria orientalis in ticks and their host, the Mithun, a comprehensive study was undertaken in the two northeastern states of India, viz. Nagaland and Arunachal Pradesh. A total of 340 of Rhipicephalus microplus ticks and 25 Ambylomma sp. ticks were screened for the presence of Theileria orientalis through PCR. Among the R. microplus ticks examined, 25 of them tested positive for T. orientalis infection whereas none of the Amblyomma ticks was positive. Additionally, a total of 275 blood samples were collected from Mithun from Arunachal and Nagaland and 31 animals were found to be positive for T. orientalis infection. Notably, six positive cases were identified in Porba (Phek district), six in Tening, and one in Bamsiakilwa village (Peren district) of Nagaland. Moreover, out of the 41 animals examined at Medziphema farms, Nagaland, 18 were found to be positive for T. orientalis infection. Moreover, the phylogenetic investigation has unveiled the presence of the highly pathogenic Type 2 (Ikeda) T. orientalis genotype in Mithun, supported by a strong bootstrap value of 100%. This study marks the initial documentation of oriental theileriosis in mithun. It underscores the need for vigilant monitoring and active surveillance of mithun populations in the northeastern states of India. Timely treatment of infected animals is imperative to avert economic losses for the farmers.

An epidemiological survey of vector-borne pathogens infecting cattle in Kyrgyzstan

Cattle production is a major contributor to the national economy of Kyrgyzstan. Most cattle in Kyrgyzstan are managed via extensive systems and graze in communal pastures. As a result, infestations with ectoparasites are widespread, implying that various vector-borne diseases might be common in cattle. However, methods to control such infectious diseases are not available in Kyrgyzstan because the epidemiology of vector-borne pathogens (VBPs) infecting cattle remains unclear. The present study was therefore designed to survey Kyrgyz cattle for VBPs. We prepared blood DNA samples from 319 cattle in Kyrgyzstan and screened them with specific PCR assays for detecting Babesia bovis, Babesia bigemina, Babesia naoakii, Theileria annulata, Theileria orientalis, Trypanosoma evansi, Trypanosoma theileri, and Anaplasma marginale infections. Our findings indicated that the surveyed cattle were infected with six of the eight pathogens targeted, with the exceptions being B. naoakii and Try. evansi. The most common pathogen was T. orientalis (84.3%), followed by B. bigemina (47.6%), T. annulata (16.6%), A. marginale (11.6%), Try. theileri (7.2%), and B. bovis (2.5%). Additional screening of the B. bovis- and B. bigemina-negative samples with a Babesia genus-specific 18S rRNA PCR identified two positive samples, and sequencing analysis confirmed that each of them was infected with either Babesia major or Babesia occultans. To the best of our knowledge, this is the first report of B. bovis, B. bigemina, B. occultans, Try. theileri, and A. marginale infections in cattle in Kyrgyzstan. Our findings suggest that cattle in Kyrgyzstan are at high risk of infectious diseases caused by VBPs.

Tick-borne Pathogen Detection and Its Association with Alterations in Packed Cell Volume of Dairy Cattle in Thailand

Tick-borne diseases (TBDs) massively impact bovine production. In endemic countries, animals are often subclinically infected, showing no signs of the illness. Anemia is a hallmark of TBDs, but there is inadequate information on its presence in infected Thai cattle. In the present study, 265 cattle from four provinces in Thailand were surveyed to identify tick-borne pathogens (TBPs) and to evaluate the changes in the packed cell volume (PCV) values associated with detection. Microscopy and polymerase chain reaction (PCR) were also compared for TBP detection. Babesia/Theileria/Hepatozoon was detected in 33.58% (89/265) of the cattle samples. Specifically, Babesia bovis (9/265), B. bigemina (12/265), Theileria orientalis (62/265), and Anaplasma marginale (50/265) were identified using species-specific assays. Significant decreases in the mean PCV levels were observed in cattle that were positive for at least one TBP (p < 0.001), Babesia/Theileria/Hepatozoon (p < 0.001), T. orientalis (p < 0.001), and A. marginale (p = 0.049). The results of PCR and microscopy for the detection of TBPs suggested slight and fair agreement between the two detection tools. The present findings contribute to a better understanding of TBDs in the field and shall facilitate the formulation of effective control for TBDs in Thailand.

Molecular Detection and Phylogenetic Analyses of Babesia spp. and Theileria spp. in Livestock in Bangladesh

Piroplasmosis, caused by Babesia spp. and Theileria spp., poses significant constraints for livestock production and upgradation in Bangladesh. Besides examining blood smears, few molecular reports are available from some selected areas in the country. Therefore, the actual scenario of piroplasmosis in Bangladesh is deficient. This study aimed to screen the piroplasms in different livestock species by molecular tools. A total of 276 blood samples were collected from cattle (Bos indicus), gayals (Bos frontalis) and goats (Capra hircus) in five geographies of Bangladesh. After that, screening was conducted through a polymerase chain reaction, and species were confirmed by sequencing. The prevalence of Babesia bigemina, B. bovis, B. naoakii, B. ovis, Theileria annulata and T. orientalis was 49.28%, 0.72%, 1.09%, 32.26%, 6.52% and 46.01%, respectively. The highest prevalence (79/109; 72.48%) of co-infections was observed with B. bigemina and T. orientalis. The phylogenetic analyses revealed that the sequences of B. bigemina (BbigRAP-1a), B. bovis (BboSBP-4), B. naoakii (AMA-1), B. ovis (ssu rRNA) and T. annulata (Tams-1) were included in one clade in the respective phylograms. In contrast, T. orientalis (MPSP) sequences were separated into two clades, corresponding to Types 5 and 7. To our knowledge, this is the first molecular report on piroplasms in gayals and goats in Bangladesh.

A U.S. Isolate of Theileria orientalis Ikeda Is Not Transstadially Transmitted to Cattle by Rhipicephalus microplus

Theileria orientalis Ikeda has caused an epidemic of bovine anemia and abortion across several U.S. states. This apicomplexan hemoparasite is transmitted by Haemaphysalis longicornis ticks; however, it is unknown if other North American ticks are competent vectors. Since the disease movement is largely determined by the host tick range(s), the prediction of the T. orientalis spread among U.S. cattle populations requires determination of additional competent tick vectors. Although Rhipicephalus microplus has mostly been eradicated from the U.S., outbreaks in populations occur frequently, and the U.S. remains at risk for reintroduction. Since R. microplus is a vector of Theileria equi and T. orientalis DNA has been detected in R. microplus, the goal of this study was to determine whether R. microplus is a competent vector of T. orientalis. Larval R. microplus were applied to a splenectomized, T. orientalis Ikeda-infected calf for parasite acquisition, removed as molted adults, and applied to two T. orientalis naïve, splenectomized calves for transmission. After 60 days, the naïve calves remained negative for T. orientalis by PCR and cytology. Additionally, T. orientalis was not detected in the salivary glands or larval progeny of acquisition-fed adults. These data suggest that R. microplus is not a competent vector of the U.S. T. orientalis Ikeda isolate.

Multiplex PCR for rapid differential diagnosis of co-prevalent species of Theileria (Theileria annulata and Theileria orientalis) in cattle

Theileriosis is a tick-borne disease that causes enormous losses in the dairy industry. There are several species of Theileria that can infect bovines. Generally, more than one species are prevalent in any geographical area; thus, chances of co-infections are high. Differentiation of these species may not be possible by microscopic examination or serological tests. Therefore, in this study, a multiplex PCR assay was standardized and evaluated for rapid and simultaneous differential detection of two species of Theileria viz., Theileria annulata and Theileria orientalis. Species-specific primers were designed to target the merozoite piroplasm surface antigen gene (TAMS1) of T. annulata and the major piroplasm surface protein gene of T. orientalis, yielding specific amplicon of 229 bp and 466 bp, respectively. The sensitivity of multiplex PCR was 10² and 10³ copies for T. annulata and T. orientalis, respectively. The simplex and multiplex PCRs were specific and showed no cross-reactivity with other hemoprotozoa for either primer. For comparative evaluation, blood samples from 216 cattle were tested by simplex and multiplex PCR for both species. Using multiplex PCR, 131 animals were found infected for theileriosis, of which 112 were infected with T. annulata, five were infected with T. orientalis, and 14 had mixed infections. This is the first report of T. orientalis from Haryana, India. Representative sequences of T. annulata (ON248941) and T. orientalis (ON248942) were submitted in GenBank. The standardized multiplex PCR assay used in this study was specific, sensitive, for the screening of field samples.

Oriental theileriosis associated with a new genotype of Theileria orientalis in buffalo (Bubalus bubalis) calves in Uttar Pradesh, India

Theileria orientalis is known to cause a benign infection in cattle and buffalo (Bubalus bubalis). However, the Ikeda and Chitose genotypes of the parasite cause lethal disease in beef and dairy cattle. Recently an outbreak of clinical oriental theileriosis occurred in buffalo calves in a Government Animal Husbandry and Agricultural Farm located in Uttar Pradesh, India. Examination of Giemsa stained thin blood smears revealed typical rod-shaped T. orientalis piroplasms in the erythrocytes. The clinical signs included pyrexia, nasal discharge, lacrimation, lethargy, inappetence and anaemia with varying degrees of paleness of the visible mucous membranes. Vascular congestion in internal organs, pulmonary emphysema and consolidation of lungs, focal areas of necrosis in the heart with mononuclear cell infiltration, focal mononuclear cell aggregation in the cortex and tubular degeneration of the kidney were significant necropsy findings. The T. orientalis major piroplasm surface protein (MPSP) gene was amplified by polymerase chain reaction (PCR) using specific primers. The nucleotide sequence analysis of the PCR product revealed 84.8% identity between the T. orientalis Uttar Pradesh isolate and other reference genotypes available in the public domain. Furthermore, the phylogenetic analysis of the MPSP gene sequence ratified that this is a new genotype of T. orientalis. This is the first report of a clinical outbreak of oriental theileriosis in Indian buffalo calves caused by a novel genotype of T. orientalis.

Theileria and Babesia infection in cattle - First molecular survey in Kazakhstan

Central Asia, including Kazakhstan, is an endemic area of Theileria and Babesia infections in cattle. Current data on the geographic distribution, prevalence, and genetic diversity of these pathogens in vertebrate hosts are lacking in Kazakhstan. The present study aimed to fill this gap, using molecular techniques for the first time. A cross-sectional survey was performed on adult cattle from 40 villages in nine administrative districts of the provinces of Turkistan and Zhambyl, southern Kazakhstan, in summer 2020. A total of 766 blood samples were screened for Theileria annulata (enolase gene), Theileria orientalis (major piroplasm surface protein gene, MPSP) and Babesia spp. (18 S ribosomal RNA gene) using polymerase chain reaction. The genetic variability of Theileria spp. was assessed by sequencing one amplicon from each village. All Babesia spp. positive amplicons were sequenced to identify the species involved. The overall prevalence of infections with T. annulata, T. orientalis and Babesia spp. was 83.0% (40 villages positive), 33.3% (31 villages) and 13.5% (36 villages), respectively. Co-infections with two or three species were present in 48.9% of all positive cattle. Theileria annulata showing a high polymorphism of the enolase gene occurred with similar frequency in both provinces. Theileria orientalis was detected for the first time in Kazakhstan being significantly (P = 0.014) more prevalent in Zhambyl than in Turkistan. Fourteen genotypes of T. orientalis were identified; two belonged to the moderately virulent MPSP-type 1 ('Chitose') and the others to MPSP-type 3 ('Buffeli') which is considered avirulent. The prevalence of Babesia infection was significantly (P < 0.000) higher in Turkistan than in Zhambyl. An unequivocal identification of the species involved was possible in 127 sequenced samples: Babesia occultans was the most common species, followed by Babesia bigemina and Babesia major, the latter being the first record in the country. The results show that Theileria and Babesia infections in cattle are widespread and occur with remarkably high prevalence in the southern Kazakhstan. They also provide first data on the genetic diversity of the species involved.

Theileria infection in bullfighting cattle in Thailand

Background and Aim

An apicomplexan protozoan parasite, namely, Theileria, primarily causes theileriosis in cattle worldwide. The virulence of the disease has been neglected because of it's low pathogenicity. However, the disease can have a substantial effect, depending on the virulence of the species, low host immunity, and coinfection. In Thailand, the molecular detection of Theileria infection in bullfighting cattle and its hematological alterations have not been reported. Thus, this study aimed to identify Theileria species in bullfighting cattle in Thailand.

Materials and Methods

Blood samples were collected from bullfighting cattle presented at the Prince of Songkla University Animal Hospital and were determined on the basis of hematological evaluation and DNA extraction. Molecular detection using the 18s rRNA and merozoite surface antigen genes was conducted for Theileria spp. and Theileria orientalis, respectively. In addition, bidirectional sequencing of the positive samples was performed. Hematological alterations between Theileria infected and uninfected groups were statistically evaluated.

Results

The levels of Theileria spp. and T. orientalis infection in bullfighting cattle were 44.62% (58/130) and 41.54% (54/130), respectively. Theileria orientalis, Theileria sinensis, and Theileria spp. infections were identified in bullfighting cattle samples. Hematological evaluation indicated that the red blood cell (RBC) level was significantly lower in Theileria-infected cattle.

Conclusion

This study was the first to use molecular techniques in the identification of Theileria infection in bullfighting cattle in Thailand, with nearly one-half of the study population infected. Theileria infection in bullfighting cattle altered the RBC level, resulting in anemia. Therefore, tick control measures should be promoted.

Detection of Theileria orientalis Genotypes from Cattle in Kyrgyzstan

The ikeda and chitose genotypes of Theileria orientalis, which for many years were thought to be benign, cause a disease that results in significant economic losses in the cattle industry. This study was carried out in order to determine the genotypes of T. orientalis in cattle in Kyrgyzstan, and 149 archived DNA samples known to be T. orientalis were analyzed by the PCR amplification of the major piroplasm surface protein (MPSP) gene region. Single-Strand Conformation Polymorphism (SSCP) analysis was performed to uncover the nucleotide changes in the archived DNA samples, and 15 samples showing different band profiles were subjected to sequence analysis. As a result of the sequence analysis, it was seen that the samples belonged to the buffeli and chitose A genotypes. In order to identify mixed genotypes, PCR was performed using primers specific for these genotypes, and buffeli (type 3), chitose (type 1) and buffeli+chitose were found to be positive in 26.2%, 2% and 71.8% of samples, respectively. As a result of this study, we showed the presence of buffeli (type 3) and chitose (type 1) genotypes of T. orientalis in cattle in Kyrgyzstan. Comprehensive epidemiological studies are needed to understand the clinical infections caused by the pathogenic chitose A and to determine the geographical distribution and different genotypes of T. orientalis.

First study on molecular detection of hemopathogens in tabanid flies (Diptera: Tabanidae) and cattle in Southern Thailand

Background and Aim:

Female tabanids play a key role in disease transmission as mechanical vectors for various hemopathogens, but only a limited number of studies have been conducted on them. This study aimed to investigate the occurrence of hemopathogens in tabanid flies compared to those found in nearby cattle hosts.

Materials and Methods:

Tabanids were collected using a Nzi trap for three consecutive days per month during the dry season (February–May 2021). Furthermore, blood samples were collected from 20 beef cattle (Bos taurus) raised in the same area where the flies were captured. Conventional polymerase chain reaction (PCR) was used to detect hemopathogenic DNA in flies and beef cattle.

Results:

In total, 279 female tabanids belonging to five species were collected: Tabanus megalops, Tabanus rubidus, Tabanus mesogaeus, Chrysops dispar, and Chrysops fuscomarginalis. Notably, T. megalops was the most abundant species, accounting for 89.2% of the flies collected (n = 249). PCR technique revealed that 76.6% of T. megalops carried at least one pathogen (Anaplasma, Ehrlichia, Babesia, or Theileria). In addition, all beef cattle had multiple hemopathogenic infections (Anaplasma marginale, Ehrlichia spp., Babesia bigemina, Babesia bovis, and Theileria spp.).

Conclusion:

Although T. megalops could carry many hemopathogens, it might not be an important vector due to the limited number of flies and parasitic load. Furthermore, T. megalops could be utilized to monitor the presence of hemopathogens in the study area, but not the disease occurrence in the individual host species. Knowing the presence of hemopathogens in flies could help manage the disease in this area.

Incidence of hemoparasitic infections in cattle from central and northern Thailand

Background

Hemoparasites, such as Babesia spp., Theileria spp. and Anaplasma spp., can negatively affect the health of farm animals resulting in significant losses in production. These losses inherently affect the economics of the livestock industry. Since increases in the severity of vector-borne diseases in the southeast Asian region have been reported, investigations of parasitic epidemiology in Thailand will be necessary to improve the existing parasite control strategies for blood parasitic infections. This study aims to investigate incidences of bovine hemoparasites throughout central and northern Thailand by focusing on areas of high-density cattle populations.

Methods

Blood parasitic infections among cattle were screened and identified by microscopic examination. Anemia status was then determined by evaluation of the packed cell volume (PCV) of each animal. Furthermore, blood parasites were detected and identified by genus and species-specific primers through the polymerase chain reaction method. Amplicons were subjected to DNA sequencing; thereafter, phylogenetic trees were constructed to determine the genetic diversity and relationships of the parasite in each area.

Results

A total of 1,066 blood samples were found to be positive for blood parasitic infections as follows: 13 (1.22%), 389 (36.50%), and 364 (34.15%) for Babesia bovis, Theileria orientalis, and Anaplasma marginale, respectively. Furthermore, multiple hemoparasitic infections in the cattle were detected. The hematocrit results revealed 161 hemoparasitic infected samples from 965 blood samples, all of which exhibiting indications of anemia with no significant differences. Sequence analysis of the identified isolates in this study revealed that B. bovis rap-1, four separate clades of T. orientalis msps, and A. marginale msp4 exhibited considerable sequence similarity to homologous sequences from isolates obtained from other countries. Sequence similarity ranged between 98.57-100%, 83.96-100%, and 97.60-100% for B. bovis rap-1, T. orientalis msps, and A. marginale msp4, respectively.

Conclusion

In this study, the analyzed incidence data of cattle hemoparasitic infection in Thailand has provided valuable and basic information for the adaptation of blood-borne parasitic infections control strategies. Moreover, the data obtained from this study would be useful for future effective parasitic disease prevention and surveillance among cattle.

Survey of tick species and molecular detection of selected tick-borne pathogens in Yanbian, China

Ticks and tick-borne diseases pose a significant threat to public health. In this study, we aimed to determine the tick species distribution and pathogens carried by ticks in Yanbian, China. A total of 2673 questing ticks were collected from eight counties and cities in Yanbian and were morphologically identified. The presence of Candidatus Rickettsia tarasevichiae (CRT), spotted fever group Rickettsia (SFGR), severe fever thrombocytopenia syndrome virus (SFTSV), Theileria, and other pathogens was confirmed using polymerase chain reaction (PCR) and real-time quantitative PCR assays, followed by phylogenetic and genotypic analyses. According to the morphological identification, the tick species in Yanbian consisted of Haemaphysalis longicornis, Ixodes persulcatus, Dermacentor silvarum, H. japonica, and H. concinna. In H. longicornis, CRT, SFGR, SFTSV and Theileria orientalis were detected, while CRT, SFGR, and SFTSV were detected in I. persulcatus, H. japonica, and D. silvarum. Only SFTSV was detected in H. concinna. Mixed infection with CRT and SFTSV was observed in I. persulcatus and H. japonica. The gene sequences of all tested pathogens exhibited 95.7%–100% identity with the corresponding sequences deposited in GenBank. Phylogenetic analysis showed that different SFGR and SFTSV genotypes were closely related to the Korean strains. This study is the first to describe the genetic diversity of SFGR Candidatus Rickettsia longicornii in H. longicornis in Yanbian, China, using the ompA, ompB, sca4, and rrs genes. These results provide epidemiological data to support the prevention and control of ticks and tick-borne diseases in the border areas of China, North Korea, and Russia.

Complete Genomes of Theileria orientalis Chitose and Buffeli Genotypes Reveal within Species Translocations and Differences in ABC Transporter Content

Theileria orientalis causes losses to cattle producers in Eastern Asia, Oceania and, more recently, North America. One pathogenic genotype (Ikeda) has been sequenced to the chromosomal level, while only draft genomes exist for globally distributed Chitose and Buffeli genotypes. To provide an accurate comparative gene-level analysis and help further understand their pathogenicity, we sequenced isolates of the Chitose and Buffeli genotypes of T. orientalis using long-read sequencing technology. A combination of several long-read assembly methods and short reads produced chromosomal-level assemblies for both Fish Creek (Chitose) and Goon Nure (Buffeli) isolates, including the first complete and circular apicoplast genomes generated for T. orientalis. Comparison with the Shintoku (Ikeda) reference sequence showed both large and small translocations in T. orientalis Buffeli, between chromosomes 2 and 3 and chromosomes 1 and 4, respectively. Ortholog clustering showed expansion of ABC transporter genes in Chitose and Buffeli. However, differences in several genes of unknown function, including DUF529/FAINT-domain-containing proteins, were also identified and these genes were more prevalent in Ikeda and Chitose genotypes. Phylogenetics and similarity measures were consistent with previous short-read genomic analysis. The generation of chromosomal sequences for these highly prevalent T. orientalis genotypes will also support future studies of population genetics and mixed genotype infections.

Molecular epidemiology and genetic characterization of Theileria orientalis in cattle

Theileria orientalis (T. orientalis) is a benign species of Theileria that is found all throughout the world, including Egypt. The purpose of this work was to determine the current status of T. orientalis infection in cattle, as well as to define T. orientalis genetic diversity using the major piroplasm surface protein (MPSP) genes. In 2020, blood samples from 500 asymptomatic cattle were collected, which live in four different governorates at northern Egypt and examined using PCR assay based on MPSP gene. Overall, 44 blood samples (8.8%, 44/500) were positive for T. orientalis, and the highest prevalence rate was observed in Kafer ElSheikh while it was relatively low in Gharbia governorate. Moreover, based on multivariable analysis, the risk of infection with T. orientalis infection was higher in mixed breed cattle and in animals of age group more than 3 years compared to other. Additionally, absence of acaricide application, infestation with ticks, and communal grazing system were identified as potential risk factors for T. orientalis infection. Phylogenetic analysis revealed that the isolates studied belonged to two MPSP genotypes, types 1 and 2. These findings reveal that the MPSP genotypes discovered in the present work displayed genetic variation that was linked to geographic area. Therefore, further research should be focused on developing an effective T. orientalis monitoring and preventive program.

Protozoan and Rickettsial Pathogens in Ticks Collected from Infested Cattle from Turkey

Diseases caused by tick-transmitted pathogens including bacteria, viruses, and protozoa are of veterinary and medical importance, especially in tropical and subtropical regions including Turkey. Hence, molecular surveillance of tick-borne diseases will improve the understanding of their distribution towards effective control. This study aimed to investigate the presence and perform molecular characterization of Babesia sp., Theileria sp., Anaplasma sp., Ehrlichia sp., and Rickettsia sp. in tick species collected from cattle in five provinces of Turkey. A total of 277 adult ticks (males and females) were collected. After microscopic identification, tick pools were generated according to tick species, host animal, and sampling sites prior to DNA extraction. Molecular identification of the tick species was conducted through PCR assays. Out of 90 DNA pools, 57.8% (52/90) were detected to harbor at least 1 pathogen. The most frequently-detected pathogens were Babesia bovis, with a minimum detection rate of 7.9%, followed by Ehrlichia sp. (7.2%), Theileria annulata (5.8%), Coxiella sp. (3.3%), Anaplasma marginale (2.5%), Rickettsia sp. (2.5%), and B. occultans (0.7%). Rickettsia sp. identified in this study include Candidatus Rickettsia barbariae, R. aeschlimannii, and Rickettsia sp. Chad. All sequences obtained from this study showed 99.05−100% nucleotide identity with those deposited in GenBank (query cover range: 89−100%). This is the first molecular detection of Rickettsia sp. Chad, a variant of Astrakhan fever rickettsia, in Turkey. Results from this survey provide a reference for the distribution of ticks and tick-borne pathogens in cattle and expand the knowledge of tick-borne diseases in Turkey.

Molecular Detection and Genetic Diversity of Tick-Borne Pathogens in Goats from the Southern Part of Thailand

Tick-borne hemoprotozoan and rickettsial diseases affect the health and productivity of small ruminants in tropical and subtropical regions. Despite the large population of goats in the southern part of Thailand, there is limited information on the prevalence of tick-borne pathogens. In this study, polymerase chain reaction was used to detect the presence of Theileria spp., T. ovis, T. orientalis, Babesia ovis, Anaplasma ovis, and A. marginale in 262 goats from three provinces in the southern part of Thailand. In this investigation, Theileria spp. and A. ovis were detected while T. ovis, B. ovis, and A. marginale were not detected. Overall infection rates of Theileria spp. and A. ovis were 10.3% and 1.5%, respectively. The co-infections of two parasites was observed in 1.5% of goats. Sequence analysis showed the presence of T. luwenshuni and T. orientalis in the goat samples. This study is the first to use the molecular detection of T. orientalis in Thai goats, and presents genetic characterization using the major piroplasm surface protein (MPSP) gene. In the phylogenetic analysis, the T. orientalis MPSP sequence was classified as type 7. The A. ovis major surface protein 4 (MSP4) gene sequences shared high identities and similarity with each other and clustered with isolates from other regions. This study provides information about the prevalence and genetic diversity of tick-borne pathogens in goats in the study area, and is expected to be valuable for the development of effective control measures to prevent disease in animals in Thailand.

Theileria-free grazing of dairy heifers on grassland in Kyushu, Japan where T. orientalis was epidemic before a 7-year vacancy

This study aimed to produce a Theileria-free grazing system for Holstein heifers reared on a dairy farm in the Hita area, Kyushu, Japan. In the grazing area, spreading of T. orientalis infection was confirmed in 2009. To eradicate the T. orientalis infection, four measures were conducted: 1) 7-year deferred grazing; 2) grazing only T. orientalis-uninfected heifers; 3) anemia check by red blood cell parameters at least once per month; and 4) protecting heifers from blood-sucking T. orientalis-infected ticks. Grazing was restarted in 2017 in the same area and continued to 2021. During last 2 years of pasturing (2020–2021) all of the 129 heifers were confirmed to be T. orientalis-free. In summary, it is possible to establish a T. orientalis-free grazing system by conducting appropriate measures.

Molecular Detection and Characterization of Babesia and Theileria in Cattle and Water Buffaloes from Southern Luzon, Philippines

Babesia and Theileria are tick-borne protozoan parasites that can cause significant economic losses in the cattle industry. This study aimed to contribute to the limited epidemiological data on Theileria orientalis as well as Babesia bigemina and B. bovis in large ruminants in the Philippines. Blood samples of 412 cattle and 108 water buffalo collected from four provinces in Southern Luzon, Philippines, were initially tested for the 18S rRNA gene of piroplasms through nested PCR. Positive samples were further subjected to species-specific PCR. The 18s rRNA of piroplasms was detected in 123 (29.9%) cattle and three (2.8%) water buffaloes. Theileria orientalis was found to be the most common piroplasm in cattle with a detection rate of 17.5%, followed by Babesia bovis and B. bigemina. Co-infections were also observed. Two water buffaloes were found infected with B. bovis, while one was positive for B. bigemina. The phylogenetic tree for B. bovis showed clustering of the isolates in two clades together with isolates from other countries, and a third separate clade. Meanwhile, the T. orientalis isolates in this study were distributed in three clades together with reported isolates from other countries. This study confirms the presence of T. orientalis in the Philippines and reports the genetic diversity of B. bovis and T. orientalis.

Molecular detection of Borrelia burgdorferi (sensu lato) and Rickettsia spp. in hard ticks distributed in Tokachi District, eastern Hokkaido, Japan

Ticks transmit various pathogens, including parasites, bacteria and viruses to humans and animals. To investigate the ticks and the potentially zoonotic pathogens that they may carry, questing ticks were collected in 2017 from 7 sites in Tokachi District, eastern Hokkaido, Japan. A total of 1563 ticks including adults (male and female), nymphs and larvae were collected. Four species of ticks were identified: Ixodes ovatus, Ixodes persulcatus, Haemaphysalis japonica and Haemaphysalis megaspinosa. Of the 1563 ticks, 1155 were used for DNA extraction. In total, 527 individual tick DNA samples prepared from adults (n = 484), nymphs (n = 41) and larvae (n = 2); and 67 pooled tick DNA samples prepared from larval stages (n = 628) were examined using PCR methods and sequencing to detect Borrelia burgdorferi (sensu lato) and Rickettsia spp. The phylogenetic analysis of Borrelia spp. flaB gene sequences showed the presence of the human pathogenic B. burgdorferi (s.l.) species (Borrelia garinii, Borrelia bavariensis and Borrelia afzelii) in I. persulcatus, whereas the non-pathogenic species Borrelia japonica was found only in I. ovatus. In I. persulcatus, B. garinii and/or its closely related species B. bavariensis was detected in both adults and nymphs at a prevalence of 21.9% whereas B. afzelii was found only in adults (1.8%). The prevalence of B. japonica in adult I. ovatus was 21.8%. Rickettsia species were identified through phylogenetic analysis based on gltA, 16S rRNA, ompB and sca4 genes. Four genotypes were detected in the samples which were classified into three species. The prevalence of human pathogenic Rickettsia helvetica was 26.0% in I. persulcatus adults and nymphs, 55.6% in I. persulcatus larval pools, and 1.7% in H. megaspinosa larval pools. The prevalence of “Candidatus R. tarasevichiae” was 15.4% in I. persulcatus adults and nymphs and 33.3% in I. persulcatus larval pools. The prevalence of “Candidatus R. principis” in H. megaspinosa adults and nymphs was 11.1% whereas it was detected in 3.4% of the H. megaspinosa larval pools. These results indicate that most of the risks of Lyme borreliosis and spotted fever group rickettsiosis infection in eastern Hokkaido, Japan, are restricted to I. persulcatus.

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Four species of ticks were collected in Tokachi District, eastern Hokkaido, Japan.

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Tick DNA samples were subjected to PCR to detect Borrelia spp. and Rickettsia spp.

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Borrelia garinii/Borrelia bavariensis and Borrelia afzelii were detected in Ixodes persulcatus.

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Rickettsia helvetica and “Candidatus R. tarasevichiae” were detected in I. persulcatus.

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First molecular detection of “Candidatus R. principis” in larvae of Haemaphysalis megaspinosa.

A Survey of Tick Infestation and Tick-Borne Piroplasm Infection of Cattle in Oudalan and Séno Provinces, Northern Burkina Faso

In this study, cattle farms located in Oudalan and Séno, two provinces in the Sahel region, northern Burkina Faso, were surveyed. Cattle owners were interviewed, cattle were examined for tick infestation, and ticks as well as blood samples were collected during the dry season (October). Blood DNA samples were tested for Babesia and Theileria infections using nested PCRs and sequencing. A total of 22 herds, 174 Zebu cattle were investigated at 6 different sites. Overall, 76 cattle (43.7 %) from 18 farms (81.8%) were found infested with ticks. Cattle in Séno, adult cattle (>5 years) and those owned by the Fulani ethnic group were significantly (p < 0.05) more likely to be tick-infested. A total of 144 adult ticks belonging to five species namely: Hyalomma impeltatum, Hyalomma impressum, Hyalomma rufipes, Rhipicephalus evertsi evertsi, and Rhipicephalus guilhoni were collected from the animals. Piroplasms were detected in the blood DNA of 23 (13.2%) cattle. The cattle in Séno and adult cattle were significantly more likely to be piroplasm-positive. Five pathogens diversely distributed were identified. Theileria mutans (12/174), Babesia bigemina (5/174), Theileria annulata (3/174), and Theileria velifera (3/174) were detected for the first time in northern Burkina Faso, whereas Babesia occultans (1/174) was found for the first time in cattle in West Africa. The analysis of the sequences, including B. bigemina RAP-1a, T. annulata Tams1 genes, and the 18S rRNA genes of all the five protozoa, revealed identities ranging from 98.4 to 100% with previously published sequences. Phylogenetic analysis based on the 18S rRNA gene sequences located north Burkina Faso piroplasms in the same clade as isolates from Africa and other regions of the world. Notably, T. mutans sequences were distributed in two clades: the T. mutans Intona strain clade and the Theileria sp. (strain MSD)/ Theileria sp. B15a clade, suggesting the presence of at least two strains in the area. These findings indicate that the control of ticks and tick-borne diseases should be taken into account in strategies to improve animal health in the Sahel region.

Coinfection of cattle in Virginia with Theileria orientalis Ikeda genotype and Anaplasma marginale

Theileria orientalis Ikeda is a newly identified agent of bovine infectious anemia in the United States. Although T. orientalis Ikeda is transmitted by ticks other than the tick that transmits Anaplasma marginale-a bacterial etiology of bovine infectious anemia-the geographic distributions of these 2 infectious organisms overlap, with coinfection reported in some cattle. Only anaplasmosis has an approved effective treatment in the United States. To provide rapid diagnostic information for producers with anemic animals, we developed a duplex real-time PCR (rtPCR) for A. marginale and T. orientalis. With a cutoff of 38 cycles, the duplex assay has a sensitivity of 97.0% and a specificity of 100% for A. marginale; with a cutoff of 45 cycles, the duplex assay has a sensitivity and a specificity of 100% for T. orientalis, compared to existing tests. In addition to providing a tool for improved clinical decision-making for veterinarians and producers, our rtPCR facilitates the study of coinfection of cattle in Virginia. Of 1,359 blood samples analyzed, 174 were positive for T. orientalis, 125 were positive for A. marginale, and 12 samples were positive for both T. orientalis and A. marginale. Hence, coinfection by these 2 agents of bovine infectious anemia does occur within Virginia. It is likely that this pattern of infection will be seen in other regions where T. orientalis and A. marginale infections are endemic, despite the difference in tick vectors.

Approaches to Integrated Parasite Management (IPM) for Theileria orientalis with an Emphasis on Immunity

Integrated parasite management (IPM) for pests, pathogens and parasites involves reducing or breaking transmission to reduce the impact of infection or infestation. For Theileria orientalis, the critical impact of infection is the first wave of parasitaemia from the virulent genotypes, Ikeda and Chitose, associated with the sequelae from the development of anaemia. Therefore, current control measures for T. orientalis advocate excluding the movement of naïve stock from non-endemic regions into infected areas and controlling the tick Haemaphysalislongicornis, the final host. In Australia, treatment of established infection is limited to supportive therapy. To update and expand these options, this review examines progress towards prevention and therapy for T. orientalis, which are key elements for inclusion in IPM measures to control this parasite.

High Granulocyte-Macrophage Colony Stimulating Factor to Interleukin 10 Ratio and Marked Antioxidant Enzyme Activities Predominate in Symptomatic Cattle Naturally Infected with Candidatus Mycoplasma haemobos, Theileria orientalis, Theileria sinensis and Trypanosoma evansi

The aim of this study was to measure the serum proinflammatory (IL-12, GM-CSF & IFN-γ) to anti-inflammatory (IL-10, IL-4) cytokine ratio, oxidant (MDA) level and antioxidant enzyme (SOD; GPx) activities after blood parasite infections. The blood and serum samples were obtained from 130 cattle and screened for identity of the infecting blood parasites by conventional PCR. The following blood parasite species were detected: Candidatus Mycoplasma haemobos (70/130); Theileria orientalis (65/130); Theileria sinensis (32/130); Anaplasma marginale (49/130); Anaplasma platys (7/130); and Trypanosoma evansi (4/130). The GM-CSF/IL-10 ratio showed significantly higher values in all the symptomatic blood parasite infected cattle groups except for symptomatic A. platys infected cattle groups. Anti-inflammatory cytokine immune responses were notable findings in symptomatic and asymptomatic cattle infected with C. M. haemobos and T. orientalis characterized by low serum IL-12:IL-10, IFN-γ:IL-10, IL-12:IL-4 and IFN-γ:IL-4 (p < 0.05). Therefore, high serum GM-CSF:IL:10 in the symptomatic blood parasite infected cattle, low serum IL-12:IL-10, IFN-γ:IL-10, IL-12:IL-4 and IFN-γ:IL-4 ratios in asymptomatic cattle, high MDA level, and increased antioxidant enzyme activities could be useful predictive tools for outcome of natural blood parasite infections in cattle.

Merozoites of Theileria orientalis buffeli reduce the parasitaemia of T. orientalis ikeda following tick challenge

Theileria orientalis is a tick-borne protozoal parasite causing anaemia and death in susceptible cattle. This investigation aimed to confirm whether immunisation with the "benign" buffeli genotype of T. orientalis could reduce the parasitaemia of the virulent ikeda genotype. Calves were inoculated intravenously or subcutaneously with bovine blood containing merozoites of T. orientalis buffeli and when recipients became positive by PCR, they and control calves were challenged with unfed nymphs of Haemaphysalis longicornis ticks infected as larvae with T. orientalis ikeda. All calves became positive for the challenge within 12 days after tick application. In the immunised calves, the first wave of parasitaemia with T. orientalis ikeda from 4 to 6 weeks was reduced significantly by >80 % before the parasite burden declined into the carrier state by 9 weeks. The parasitaemias in two calves which exhibited low infections with T. orientalis ikeda shortly after arrival, were also significantly reduced after tick challenge. The results confirm the previous studies on immunity to T. sergenti in Japan, and field experience with theileriosis in endemic zones where the carrier state appears to prevent clinical disease despite repeated, seasonal tick infestations with virulent genotypes of the parasite. This method offers a means to reduce the severity of the first wave of theilerial parasitaemia after tick challenge and possibly recover associated production losses.

Molecular detection of Theileria species, Anaplasma species, Candidatus Mycoplasma haemobos, Trypanosoma evansi and first evidence of Theileria sinensis-associated bovine anaemia in crossbred Kedah-Kelantan x Brahman cattle

BACKGROUND

Serious disease outbreaks in cattle are usually associated with blood pathogens. This study aims to detect blood pathogens namely Theileria species, Anaplasma species, Candidatus Mycoplasma haemobos and Trypanosoma evansi, and determine their phylogenetic relationships and haemato-biochemical abnormalities in naturally infected cattle.

METHODS

Molecular analysis was achieved by PCR amplification and sequencing of PCR amplicons of 18SrRNA gene of Theileria species, 16SrRNA genes of Anaplasma and Mycoplasma species, MPSP genes of T. orientalis and T. sinensis, MSP4 gene of A. marginale, 16SrRNA gene of Candidatus Mycoplasma haemobos, and RoTat1.2 VSG gene of Trypanosoma evansi, in sixty-one (61) clinically ill Kedah-Kelantan x Brahman cattle in Pahang, Malaysia.

RESULTS

A total of 44 (72.13%) cattle were infected with more than one blood pathogen. Theileria species was the blood pathogen with the highest molecular detection rate (72.13, 95% CI 59.83-81.81%). Nucleotide blast analyses of all sequences demonstrated high degree of molecular similarity (98-100%) in comparison with their respective reference sequences. Analysis of 18SrRNA gene sequences of Theileria species and 16SrRNA gene sequences of Anaplasma species revealed Theileria sinensis and Anaplasma platys respectively as additional species detected in these cattle. MPSP-PCR analysis was conducted for further confirmation of T. sinensis. The blood picture of eight infected cattle groups revealed poikilocytosis, anisocytosis, rouleaux formation and degenerative left shift. High mean erythrocyte fragility values were common in infected cattle groups. Anaemia of the macrocytic normochromic type and spherocytes were observed in the T. evansi and Anaplasma platys + Theileria sinensis double species co-infected cattle group. Normocytic normochromic anaemia was observed in the T. sinensis infected cattle group. Significant (p < 0.05) increases in serum liver and kidney parameters, total protein, globulin, total and unconjugated bilirubin and decreased albumin values were observed in the T. evansi infected cattle when compared to clinically healthy cattle.

CONCLUSION

We present the first evidence of Theileria sinensis-associated bovine anaemia (TSABA) in Malaysian cattle. Because of the high occurrence of bovine theileriosis and detection of A. platys, there is an urgent need for appropriate preventive and control measures against these blood pathogens.

A longitudinal study of infection with genotypes of Theileria orientalis in calves and introduced cattle at Dorrigo, New South Wales, and the effect on weight gains

BACKGROUND

In regions with endemic Theileria orientalis, recovered cattle are carriers, leaving newborn calves and introduced stock as the most susceptible groups to develop clinical disease after tick infestation with parasite transmission.

METHODS

To gain information on the kinetics of infection and development and effects of theileriosis caused by virulent ikeda and chitose genotypes and the "benign" buffeli genotype of T.orientalis, this study sampled a total of 134 calves from 3 farms in Dorrigo, Australia, a region with multiple genotypes of the parasite. In addition, 30 introduced beef weaners were bled and weighed for 6 months after arrival.

RESULTS

In both cohorts, parasitaemia with the ikeda and chitose (genotypes 1 & 2) of T.orientalis was detectable by PCR within 3-4 weeks in >95 % of the groups, with maximal gene copies generated around 5-7 weeks after birth or introduction, before declining. In contrast, parasitaemias of T.orientalis buffeli (genotype 3), increased slowly, with around 80 % of the population testing positive by PCR after 4 months. The parasitaemias of the buffeli genotype did not exceed 40,000 gene copies /ul and were similar to those exhibited by ikeda and chitose genotypes following the "first wave of parasitaemia" as cattle entered the carrier state. In the 30 introduced weaners, the early infection with T.orientalis ikeda and chitose also caused significant reductions in packed cell volume (PCV) and incurred an estimated 20Kg loss in weight gain; the latter had not been recovered by 6 months after introduction.

CONCLUSIONS

The results support previous findings in other endemic regions of theileriosis, and imply that amelioration of the early high levels of parasitosis by the virulent genotypes could reduce the initial impact of theileriosis on production, which appears much less affected once animals enter the carrier state.

Effects of Theileria orientalis Infection on Health Status and Productivity of Dairy Cows Reared inside Barns

The objective of the present study was to investigate the effects of Theileria orientalis on the severity of anemia, the prevalence of disease within 21 days after calving and productivity in cows raised inside barns. This longitudinal observational study, which was conducted on a commercial dairy farm in Japan, involved 627 Holstein cows subjected to PCR analysis for T. orientalis. In study 1, we collected blood samples from 156 sick cows within 21 days after calving, and we found the prevalence of T. orientalis infection to be 65.4%. In study 2, we randomly selected 471 cows during the dry period and collected blood samples to conduct PCR analysis for T. orientalis and determined the prevalence of T. orientalis infection to be 69.0%. Compared with the values for the T. orientalis-uninfected group, the T. orientalis-infected cows had significantly decreased hemoglobin concentrations and hematocrit, but there were no differences in the other complete blood count indexes between the two groups. In addition, there were no differences in productivity and the prevalence of major diseases between the T. orientalis-infected and uninfected cows. In summary, T. orientalis had few effects on anemia, productivity and the health of cows raised inside a barn.

Endemic infection of cattle with multiple genotypes of Theileria orientalis on the Northern Tablelands of New South Wales despite limited presence of ticks

Bovine theileriosis, caused by the Theileria orientalis complex, causes a mild persistent infection with the severity dependent on the infecting genotype and host exposure status. Clinical theileriosis was first detected on the Northern Tablelands of NSW in 2009 and a high prevalence of infection in cattle reported in 2013. However, the parasite was not genotyped and likely vectors not investigated. In response to ongoing clinical cases, here we identify the Theileria genotypes present in the region and potential vectors. Genotype-specific multiplex qPCR of 90 blood samples from eight farms revealed a 100 % prevalence of T. orientalis in individual cattle with concurrent infection with all three genotypes present in 73 % of cases. The prevalence of the pathogenic genotype (Ikeda) differed significantly between farms; however, the level of parasitemia was not affected by genotype or associated with clinical disease. Parasitaemia levels were higher in heifers than cows. Questing tick collection on six of the farms between November 2017 and May 2019 yielded 358 questing ticks from one farm, all of which were morphologically identified as Haemaphysalis bancrofti. Larvae accounted for 59 % of the ticks followed by nymphs (34 %) and adults (7%). Theileria was detected only in nymphs with Ikeda and Buffeli genotypes each being detected in one of four pools of ticks. The high prevalence of co-infection with three genotypes of T. orientalis indicates that they are now endemic in the region and confirms the lack of cross-protection between genotypes. This is the first detection of T. orientalis in questing H. bancrofti ticks: indicating that it may be a vector for T. orientalis in this region. However, the high prevalence of bovine infection is at odds with the absence of captured ticks or history of tick infestation on five of the six farms raising the possibility that other vectors or transmission pathways play key roles.

Genomic Profiling for Piroplasms in Feeding Ixodid Ticks in the Eastern Cape, South Africa

Importation of tick-infected animals and the uncontrollable migration of birds and wild animals across borders can lead to geographical expansion and redistribution of ticks and pathogen vectors, thus leading to the emergence and re-emergence of tick-borne diseases in humans and animals. Comparatively, little is known about the occurrence of piroplasms in ixodid ticks in the Eastern Cape, South Africa, thus necessitating this study, which is aimed at detecting piroplasms (Theileria and Babesia) from feeding tick samples collected from cattle, sheep, and goats in selected sites in the Eastern Cape, South Africa. A total of 1200 feeding ixodid ticks collected from farm animals at selected homesteads were first subjected to molecular identification using mitochondrial 12S ribosomal RNA (rRNA) gene by PCR and were further tested for the presence of piroplasms through amplification of the 18S rRNA gene via nested-PCR followed by sequencing of the PCR products. The results indicated that 853 (71.1%) corresponded to the genus Rhipicephalus, 335 (27.9%) corresponded to genus Amblyomma, and 12 (1%) corresponded to genus Haemaphysalis. Amblyomma hebraeum and Rhipicephalus appendiculatus were the most common identified ticks from this study. The 18S rRNA nested-PCR revealed that 44 (3.7%) samples were confirmed positive for Theileria. A homology search for the generated sequences revealed a high percentage identity of 98–98.9% similarity to T. buffeli, T. orientalis, and T. sergenti in the GenBank. Based on the results obtained herein, we conclude that there is a big diversity of Theileria species; therefore, we suggest that this research should cover more geographical areas in order to reveal the true prevalence of this pathogen in the studied area because this will be a great step in the possible prevention of an outbreak that could have devastating effects on livestock production and human health in both the studied areas and South Africa at large.

A large-scale survey of Theileria orientalis infection in grazing dairy heifers in Kyushu, Japan

The objective of the present study was to investigate the prevalence of Theileria orientalis infection and the influence of this disease on dairy grazing heifers in Kyushu by monitoring red blood cell (RBC) indexes, and to evaluate the efficacy of diminazene diaceturate treatment of T. orientalis-infected animals. A monthly epidemiological survey was conducted for Holstein heifers, which were reared from 10 to 16 months of age on a large commercial dairy farm and grazed on eight independent grasslands from April to November, 2009. During the survey, a total of 2,803 blood samples were collected from the 891 grazing heifers, in which the prevalence of T. orientalis infection was 52.4%. Compared with the heifers before infection, heifers with high parasitemia (more than 100 parasites per 10⁴ RBC) had significantly decreased RBC indexes, such as RBC count, hemoglobin concentration, and hematocrit (P<0.05), whereas heifers with low parasitemia (less than 100 parasites per 10⁴ RBC) had similar RBC indexes as those before infection. Treatment with diminazene diaceturate had lower efficacy in heifers with high parasitemia than those with low parasitemia (40.7% and 73.2% became negative, respectively, P<0.05). In summary, T. orientalis infection is a potentially serious problem in Kyushu, and it is important to routinely implement control programs for heifers that are grazed on grasslands in this region.

Detection of Mycoplasma wenyonii and "Candidatus Mycoplasma haemobos" from Japanese Black breeding cows in Kyushu and Okinawa region, southern part of Japan

This study aimed to elucidate the epidemiological status of hemoplasma infection and investigate the interaction between Theileria orientalis and hemoplasmas in Japanese Black breeding cows raised in the Kyushu and Okinawa regions. Blood samples were collected from 400 cows from 80 different farms in eight prefectures (five samples per farm and 10 farms per prefecture). Mycoplasma wenyonii (Mw), “Candidatus Mycoplasma haemobos” (CMh), and T. orientalis were examined by polymerase chain reaction (PCR) assay using whole blood samples. PCR results showed that 91.5% (366/400) of cows were positive for bovine hemoplasma: 40.3% were infected with Mw only, 9.5% with CMh only, and 41.8% with both species. T. orientalis was detected in 36% (144/400) of cows. The infection rate of T. orientalis was higher in the grazing group (P<0.001) than in the housed group, while the rate of CMh infection was higher (P<0.05) in the housed group than in the grazing group, suggesting that not only the tick but also other arthropod vectors may contribute to hemoplasma transmission. Although the cows with hemoplasma dual infection showed higher (P<0.05) white blood cell counts compared with hemoplasma-negative cows, there was no difference in hematologic parameters related to the anemia between the hemoplasma-positive and -negative animals. This may indicate that Japanese Black cattle could have resistance to the anemia caused by infection with hemoplasma.

Utilizing attached hard ticks as pointers to the risk of infection by Babesia and Theileria species in sika deer (Cervus nippon yesoensis), in Japan

Ticks are hematophagous ectoparasites that have a significant impact on their animal hosts. Along with mosquitoes, they are the main arthropod vectors of disease agents in domestic animals, wildlife and humans. To investigate the occurrence and prevalence of piroplasmids in ticks, DNA was extracted from 519 hard ticks collected from 116 hunted Hokkaido sika deer (Cervus nippon yesoensis). The success of the DNA extraction was confirmed by touchdown PCR targeting the mitochondrial 16S rDNA gene of ticks. Touchdown PCR and reverse line blot (RLB) hybridization targeting the 18S rRNA gene were used to detect 14 piroplasm species. All hard ticks parasitizing Hokkaido sika deer were identified as belonging to the genera Ixodes and Haemaphysalis. In total 163 samples (31.4%) were positive for Babesia and Theileria spp. among tick species according to RLB hybridization. Tick DNA hybridized to the oligonucleotide probes of Theileria sp. Thrivae (27.0% of ticks; 140/519), Theileria capreoli (10.6%; 55/519), Babesia divergens-like (1.7%; 9/519), Babesia sp. (Bab-SD) (0.6%; 3/519), Babesia microti U.S. (0.4%; 2/519), and B. microti Hobetsu (0.4%; 2/519). The partial sequencing and phylogenetic analyses of the 18S rRNA gene confirmed the RLB hybridization results. Further investigations are needed to reveal the epidemiology and respective vectors of these pathogens.

Molecular detection and characterization of tick-borne haemoparasites among cattle on Zanzibar Island, Tanzania

Tick-borne diseases (TBDs) are serious constraints to livestock production in Tanzania and other tropical and subtropical countries and impact the livelihoods of resource-poor farming communities in the region. In Tanzania, detailed studies on tick-borne pathogens (TBPs) in cattle using sensitive molecular detection methods are scarce. The objective of this study was to investigate the occurrence and species composition of bovine TBPs in cattle kept in Zanzibar Island. A total of 236 blood samples were randomly collected in cattle population in June and July 2019. We used polymerase chain reaction (PCR) and gene sequencing to detect and identify pathogens. PCR screening of all 236 samples revealed that 64.5% of animals were infected by TBPs, including Theileria parva (34.3%), T. mutans (38.1%), T. taurotragi (30.9%), Anaplasma marginale (10.2%), Babesia bigemina (5.1%), T. velifera (3.4%) and B. bovis (2.1%). Overall a total of 86 animals (36.4%) were co-infected with up to five pathogens including T. parva, T. mutans, T. taurotragi, A. marginale and B. bigemina. The pathogens mostly involved in the co-infection were T. parva, T. taurotragi and T. mutans. Sequence analysis indicated that T. parva p104 and B. bigemina RAP1a genes are diverse among the sampled animals in Zanzibar Island, with 99.64%-100% and 99.51%-100% nucleotide sequence identity value respectively. In contrast, the A. marginale MSP-5, T. mutans 18S rRNA V4 region and B. bovis SBP-2 genes are conserved, with 100%, 99.05%-100% and 99.66%-100% nucleotide sequence identity values respectively. The phylogenetic analyses revealed that T. parva p104 and B. bigemina RAP1a gene sequences showed significant differences of genotypes, as they appear in different clades. Meanwhile, A. marginale MSP-5, T. mutans 18S rRNA V4 region and B. bovis SBP-2 gene sequences appear in the same clade with other sequences extracted from the NCBI GenBank. The epidemiological findings revealed in this study will provide important information on tick-borne diseases in Tanzania and will be used as scientific basis for planning future control strategies.

Genetic Diversity of Bovine Hemoprotozoa in South Korea

Tick-borne pathogens cause economically significant diseases in cattle. Theileria spp. are parasitic protozoa and the causative agent of bovine theileriosis. Here we report the distribution and risk factors of bovine Theileria using blood samples taken between 2018 and 2019. Of 737 tested cattle, nine animals (1.2%) were positive for Theileria orientalis infection by 18S rRNA gene amplification. Further analysis of the infected samples using the T. orientalis major piroplasm surface protein (MPSP) gene revealed five different genotypes circulating in the population: Types 1, 2, 3, 7, and N3. To the best of our knowledge, this is the first research to describe the existence of the T. orientalis MPSP genotype N3 in South Korea. Although the prevalence of bovine T. orientalis was low, our study offers data on the geographical distribution and prevalence of bovine Theileria spp. in South Korea. Further studies are warranted to determine the correlation of clinical symptoms with parasite MPSP genotypes. Our data provide epidemiological information to help control bovine theileriosis in South Korea.

Clinical Pathology, Immunopathology and Advanced Vaccine Technology in Bovine Theileriosis: A Review

Theileriosis is a blood piroplasmic disease that adversely affects the livestock industry, especially in tropical and sub-tropical countries. It is caused by haemoprotozoan of the Theileria genus, transmitted by hard ticks and which possesses a complex life cycle. The clinical course of the disease ranges from benign to lethal, but subclinical infections can occur depending on the infecting Theileria species. The main clinical and clinicopathological manifestations of acute disease include fever, lymphadenopathy, anorexia and severe loss of condition, conjunctivitis, and pale mucous membranes that are associated with Theileria-induced immune-mediated haemolytic anaemia and/or non-regenerative anaemia. Additionally, jaundice, increases in hepatic enzymes, and variable leukocyte count changes are seen. Theileria annulata and Theileria parva induce an incomplete transformation of lymphoid and myeloid cell lineages, and these cells possess certain phenotypes of cancer cells. Pathogenic genotypes of Theileria orientalis have been recently associated with severe production losses in Southeast Asia and some parts of Europe. The infection and treatment method (ITM) is currently used in the control and prevention of T. parva infection, and recombinant vaccines are still under evaluation. The use of gene gun immunization against T. parva infection has been recently evaluated. This review, therefore, provides an overview of the clinicopathological and immunopathological profiles of Theileria-infected cattle and focus on DNA vaccines consisting of plasmid DNA with genes of interest, molecular adjuvants, and chitosan as the most promising next-generation vaccine against bovine theileriosis.

Molecular Survey and Genetic Diversity of Babesia spp. and Theileria spp. in Cattle in Gansu Province, China

PURPOSE

Babesia spp. and Theileria spp. are tick-borne pathogens of livestock globally. In this study, we investigated the presence and distribution of these pathogens in cattle from 20 locations in 4 Counties of Wuwei City. The aim of the present research was to evaluate the spread of piroplasms, so as to provide the epidemiological information for control piroplasmosis in the region.

METHODS

The authors provided the molecular data for Babesia spp. and Theileria spp. and analyzed the obtained sequences of the 18S rRNA gene, Tams1 gene and MPSP gene by using the ClustalW program in MEGA version 6.06 software and BLASTn tool of NCBI GenBank database.

RESULTS

The total infection rates were detected by nPCR with 1.8% for T. orientalis, 3% for T. sinensis, 0.6% for T. annulata, 1.8% for B. motasi and 0.6% for B. bigemina.

CONCLUSIONS

To the best of our knowledge, this is the first report investigating T. sinensis from cattle by PCR in Wuwei City. In particular, ovine B. motasi has been for the first time detected in cattle in our study and its impact is worth discussing to figure out the potential reasons.

Molecular detection, prevalence and risk factors of Theileria orientalis infection among cattle in Peninsular Malaysia

There is need to confirm the presence of Theileria orientalis among the cattle population in Peninsular Malaysia and to evaluate the risk factors associated with the infection. To this effect, blood samples were collected from 1045 cattle from 43 farms throughout the entire States of Peninsular Malaysia. The collected blood samples were subjected to DNA extraction and subsequent PCR amplification of the major piroplasm surface protein (MPSP) gene of the haemoprotozoan. Representative positive amplicons were purified, sequenced and compared with other sequences of the MPSP gene of T. orientalis curated from the GenBank. A well-structured questionnaire was used to get information about each cattle, it's demography, the bio-security, environmental and management factors. Univariate and multivariate analysis were used for the statistical evaluation, with significance set at p < 0.05. A total prevalence of 49.76% (520/1045; 95% CI: 46.73 - 52.79) was obtained. Types of breeds, age, production type, herd size, level of farm biosecurity, farm size, presence of other animal species in the farm, management systems and prophylaxis were significantly (p < 0.05) associated with the prevalence of T. orientalis. This study confirmed the presence of T. orientalis and establish that the haemoprotozoan is endemic among cattle in Peninsular Malaysia.

Development and evaluation of a novel loop-mediated isothermal amplification (LAMP) method targeting Theileria parasites infecting Yezo sika deer

The increasing Yezo sika deer (Cervus nippon yesoensis) population is creating a large problem. Yezo sika deer are an important blood meal source, and these deer contribute to the maintenance of tick populations. Theileria spp. infections in Yezo sika deer and T. orientalis infections in cows occur at high frequencies, and the same tick species infests both deer and cows. Therefore, a specific detection method to identify deer Theileria spp. is important. In this study, we establish a novel molecular detection method for identifying Theileria spp. from deer and tick samples using loop-mediated isothermal amplification (LAMP). This method targets a metalloprotease/cell division cycle protein gene homologue. Our LAMP protocol was able to detect deer Theileria and did not show cross reactivity with other closely related protozoan parasites, including T. orientalis. The LAMP method showed sensitivity and specificity equivalent to those of nested PCR performed on the same field samples from deer and ticks. These results demonstrate the applicability of LAMP to field surveys in which the detection of deer Theileria spp. is required. In conclusion, due to its simplicity, specificity, and reliability, we suggest our LAMP protocol as an appropriate method for routine surveys to detect Yezo sika deer and ticks infected with deer Theileria spp. parasites. Additionally, this LAMP method offers great promise as a useful tool to distinguish Yezo sika deer Theileria from related Theileria parasites present in livestock.

Molecular prevalence of Theileria infections in cattle in Yanbian, north-eastern China

Bovine Theileria are tick-borne protozoan parasites that invade bovine erythrocytes and lymphocytes. Three main bovine Theileria species have been identified in China: T. orientalis, T. sinensis, and T. annulata. To examine the prevalence of bovine theileriosis in Yanbian, a total of 584 bovine blood samples were collected from five localities from 2017 to 2019 and analyzed by PCR. Six pairs of oligonucleotide primers directed against the 18S rRNA gene of Theileria spp., Tams-1 gene of T. annulata, MPSP gene of T. orientalis, and T. sinensis, were used to detect these parasites. A sequence analysis of the amplified genes confirmed that the Theileria species were T. orientalis and T. sinensis, without T. annulata. The overall prevalence of Theileria in cattle was 42.81% (250/584). Out of the 584 samples, 159 (27.23%) and 157 (26.88%) were positive for T. sinensis and T. orientalis, respectively, and the mixed infection rate was 11.30% (66/584). The total prevalence of bovine Theileria species in Helong, Hunchun, Longjing, Yanji, and Dunhua was 66.28%, 49.68%, 23.81%, 28.15%, and 0%, respectively. These results provide epidemiological data for the prevention and control of bovine Theileria species in Yanbian, China.

Molecular, epidemiological and haematological evaluation in Theileria orientalis infected cattle from an endemic region in India

The objective of the present study was to investigate the epidemiological and haematological parameters with simultaneous molecular detection of Theileria orientalis infection of crossbred jersey (CBJ) cattle. Haematological values like mean hemoglobin (Hb) (7.31 ± 2.3 g/dl), packed cell volume (PCV) (21.69 ± 6.11%), red blood cells count (RBCs) (4.40 ± 1.6 M/μl), white blood cells count (WBCs) (6.93 ± 3.06 103/µl) and mean corpuscular hemoglobin concentration (MCHC) (33.56 ± 3.51 g/dl) were decreased significantly (p < 0.05), whereas mean corpuscular volume (MCV) (51.06 ± 6.14fl) and eosinophil count (0.39 ± 0.44 103/µl) were significantly (p < 0.05) increased in cattle infected with T. orientalis. Analysis of major piroplasm surface protein (MPSP) of 110 blood samples randomly collected from cattle from seven districts by PCR indicated that an average of 70% of cattle was positive for T. orientalis infection. In particular, Puri and Khorda districts were identified as relatively high-risk areas for T. orientalis infection, with infection rates of 76.66% and 72.4%, respectively. The phylogenetic analysis of isolated T. orientalis MPSP gene (MN334767) classified it into type 5. Earlier Indian isolates were classified into three types viz.type 1, type 3 and type 7 and this is the first time to detect type 5 in Odisha, India.

Detection of novel piroplasmid species and Babesia microti and Theileria orientalis genotypes in hard ticks from Tengchong County, Southwest China

To reveal the genetic diversity of Babesia microti and Theileria orientalis in Southwest China, we conducted a molecular survey of piroplasms in hard ticks in a China-Myanmar border county. Host infesting and questing ticks were collected from Tengchong County in 2013 and 2014. Piroplasm infection in ticks was detected by PCR, and then, phylogenetic analysis was conducted to study the genetic diversity of the pathogens identified in ticks. All in all, six piroplasm species comprising of B. microti; B. orientalis; a novel Babesia species designated Babesia sp. Tengchong, China; T. orientalis; T. luwenshuni; and an as yet undescribed piroplasmid species referred to as Piroplasmid sp. Tengchong, China, have been identified after screening goat- and cattle-attached ticks. In addition, B. bigemina has been identified by screening questing ticks. Phylogenetic analysis based on the 18S rRNA and partial β-tubulin gene revealed two novel potentially zoonotic genotypes designated B. microti Tengchong-Type A and B. The T. orientalis genotypes identified in the present study represent the seven known genotypes 1-5, 7, and N3 as revealed by phylogenetic analysis of 18S rRNA and MPSP genes. Importantly, an additional genotype designated N4 has also been identified in this study, which brings the number of recognized T. orientalis genotypes to a total of twelve. Thus, besides the two novel species, Babesia sp. Tengchong, China, closely related to Babesia species isolated from yak and Piroplasmid sp. Tengchong, China, our study demonstrates that additional novel B. microti and T. orientalis genotypes exist in Southwest China.

An appraisal of oriental theileriosis and the Theileria orientalis complex, with an emphasis on diagnosis and genetic characterisation

Oriental theileriosis, a tick-borne disease of bovids caused by members of the Theileria orientalis complex, has a worldwide distribution. Globally, at least 11 distinct genotypes of T. orientalis complex, including type 1 (chitose), type 2 (ikeda), type 3 (buffeli), types 4 to 8, and N1-N3, have been described based on the sequence of the major piroplasm surface protein (MPSP) gene. Of these 11 genotypes, mainly ikeda and chitose are known to be pathogenic and cause considerable morbidity (including high fever, anaemia, jaundice and abortion), production losses and/or mortality in cattle. Mixed infections with two or more genotypes of T. orientalis is common, but do not always lead to a clinical disease, posing challenges in the diagnosis of asymptomatic or subclinical forms of oriental theileriosis. The diagnosis of oriental theileriosis is usually based on clinical signs, the detection of piroplasms of T. orientalis in blood smears, and/or the use of serological or molecular techniques. This paper reviews current methods used for the diagnosis of T. orientalis infections and the genetic characterisation of members of the T. orientalis complex, and proposes that advanced genomic tools should be established for investigations of these and related haemoparasites.