Phylogenetic analysis of Theileria sp. from sika deer, Cervus nippon, in Japan

Molecular detection and characterization of a novel Theileria genotype in Dama Gazelle (Nanger dama)

Wild animals play a critical role in maintenance and transmission of various tick-borne pathogens. It is essential to identify these wild host species that can serve as important reservoirs of tickborne diseases. In the present study we investigated Dama gazelle (Nanger dama) as a potential novel reservoir of Theileria spp. A total of 53 blood samples collected from Dama gazelle as part of the Al Ain Zoo preventive medicine program were screened for Theileria spp. by qPCR using a commercial assay, followed by additional studies using conventional PCR targeting an approximate 450-base pair (bp) fragment of the V4 hypervariable region of the 18S ribosomal RNA (rRNA) gene. Sequencing and phylogenetic analysis of a subset (20) of PCR amplicons revealed Theileria isolates from gazelles of Al Ain Zoo clustered closely to Theileria sp. Dama Gazelle (AY735115) from USA and were far away or did not cluster with the known Theileria spp. of ruminants namely T. annulata, T. ovis, T. orientalis, T. luwenshuni, T.parva and T.sinensis. Theileria genotypes detected in gazelles of present study were clearly distinct from the other common theileria species of ruminants. The present finding throws light on the critical role of reservoir host in maintenance and transmission of pathogen.

Theileria infection with severe anemia and unhealed fracture in a sika deer Cervus nippon aplodontus (Cervidae: Cetartiodactyla)

An adult female sika deer (Cervus nippon aplodontus) inhabiting Nara Park, Nara, Japan, had broken bone injuries from a car accident. During its treatment, we found that the sika deer had severe anemia and the fracture remained unhealed throughout. Peripheral blood smear revealed piroplasms in the erythrocytes, which were identified as merozoites of undescribed Theileria species, widely found in sika deer in Japan. This is the report of a clinical case of Theileria infection, accompanied by severe anemia in a sika deer.

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 of tick-borne protozoan parasites in sika deer (Cervus nippon) from western regions of Japan

The sika deer (Cervus nippon) is one of the most common species of wildlife in Japan. This study aimed to reveal the prevalence of tick-borne protozoan parasites in wild sika deer living in western Japan. We used nested polymerase chain reaction (PCR) to detect the 18S rRNA gene of tick-borne apicomplexan parasites (Babesia, Theileria, and Hepatozoon spp.) from 276 blood and liver samples from sika deer captured in the Yamaguchi, Oita, Kagoshima, Okayama, Ehime, Kochi, and Tokushima Prefectures. In total, 259 samples (259/276; 93.8%) tested positive in the nested PCR screening. Gene sequencing revealed that 99.6% (258/259) of positive samples contained Theileria sp. (sika 1), while Theileria sp. (sika 2), another Theileria species, was detected in only 3 samples. We also found that one sample from a sika deer captured in Kagoshima contained the gene of an unidentified Babesia sp. related to Babesia sp. Kh-Hj42, which was previously collected from tick in western Siberia. In conclusion, we found a high prevalence of piroplasms in sika deer from western Japan, and DNA analysis revealed that Theileria sp. (sika 1) had the highest infection rate.

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 detection and identification of tick-borne bacteria and protozoans in goats and wild Siberian roe deer (Capreolus pygargus) from Heilongjiang Province, northeastern China

BACKGROUND

Small ruminants are important hosts for various tick species and tick-associated organisms, many of which are zoonotic. The aim of the present study was to determine the presence of tick-borne protozoans and bacteria of public health and veterinary significance in goats and wild Siberian roe deer (Capreolus pygargus) from Heilongjiang Province, northeastern China.

METHODS

The occurrence of piroplasms, Anaplasma phagocytophilum, A. bovis, A. marginale, A. capra, A. ovis, Ehrlichia spp. and spotted fever group rickettsiae was molecularly investigated and analyzed in 134 goats and 9 free ranging C. pygargus living in close proximity.

RESULTS

Piroplasm DNA was detected in 16 (11.9%) goats and 5 C. pygargus. Sequence analysis of 18S rRNA sequences identified 3 Theileria species (T. luwenshuni, T. capreoli and T. cervi). Four Anaplasma species (A. ovis, A. phagocytophilum, A. bovis and A. capra) were identified in goats and C. pygargus. Anaplasma ovis and A. bovis were detected in 11 (8.2%) and 6 (4.5%) goats, respectively; A. phagocytophilum, A. bovis and A. capra were found in 3, 7 and 3 C. pygargus, respectively. Sequence analysis of 16S rRNA sequences revealed the presence of 5 different genetic variants of A. bovis in goats and C. pygargus, while the analysis of 16S rRNA and gltA sequence data showed that A. capra isolates identified from C. pygargus were closely related to the genotype identified from sheep and Haemaphysalis qinghaiensis, but differed with the genotype from humans. Anaplasma/Theileria mixed infection was observed in 2 (1.5%) goats and 5 C. pygargus, and co-existence involving potential zoonotic organisms (A. phagocytophilum and A. capra) was found in 2 C. pygargus. All samples were negative for A. marginale, Ehrlichia spp. and SFG rickettsiae.

CONCLUSIONS

These findings report the tick-borne pathogens in goats and C. pygargus, and a greater diversity of these pathogens were observed in wild animals. Three Theileria (T. luwenshuni, T. capreoli and T. cervi) and four Anaplasma species (A. ovis, A. phagocytophilum, A. bovis and A. capra) with veterinary and medical significance were identified in small domestic and wild ruminants. The contact between wild and domestic animals may increase the potential risk of spread and transmission of tick-borne diseases.

Differential diagnosis and molecular characterization of Theileria spp. in sika deer (Cervus nippon) in Hokkaido, Japan

Sika deer (Cervus nippon) is widely distributed in Asian countries and is one of the most common wildlife animals in Hokkaido, Japan. Previous studies identified Theileria spp. in sika deer in Japan including Theileria sp. Thrivae belonging to T. cervi group and Theileria sp. sola belonging to T. capreoli group. However, the studies failed to differentiate these two species without sequencing. Therefore, epidemiological information on cervine theileriosis in Hokkaido, Japan is limited. This study differentiated the two Theileria spp. using restriction fragments length polymorphism (RFLP). Based on the PCR-RFLP, Theileria spp. were identified in 103 (88.0%) of 117 samples, and the prevalence of each parasites were 86.3% (n = 101) and 57.3% (n = 67) for Theileria sp. Thrivae and T. capreoli-like, respectively. Phylogenetic analysis based on the 18S rRNA showed a close relationship between Theileria sp. Thrivae and T. cervi in China. In addition, phylogenetic analysis of internal transcribed spacer regions also showed a close relationship between Theileria sp. Thrivae and T. cervi.

The Babesia divergens Asia Lineage Is Maintained through Enzootic Cycles between Ixodes persulcatus and Sika Deer in Hokkaido, Japan

Parasites of the Babesiadivergens Asia lineage, which are closely related to B. divergens in Europe and Babesia sp. strain MO1 in the United States, were recently reported in sika deer (Cervus nippon) in eastern Japan. To identify the tick vector(s) for this parasite, we conducted a field survey in Hokkaido, Japan, where the infection rate in sika deer is the highest in the country. A specific PCR system which detects and discriminates between lineages within B. divergens and between those lineages and Babesia venatorum showed that Ixodes persulcatus (11/822), but not sympatric Ixodes ovatus (0/595) or Haemaphysalis sp. (0/163) ticks, carried B. divergens Asia lineage. Genomic DNA was archived from salivary glands of partially engorged I. persulcatus females and three isolates of B. divergens Asia lineage were newly described. The 18S rRNA gene sequence of the isolates formed the Asia lineage cluster with those previously described in sika deer isolates. One salivary gland also contained parasites of Babesia microti U.S. lineage, which were subsequently isolated in a hamster in vivoB. venatorum (strain Etb5) was also detected in one I. persulcatus tick. The 18S rRNA sequence of Etb5 was 99.7% identical to that of B. venatorum (AY046575) and was phylogenetically positioned in a taxon composed of B. venatorum isolates from Europe, China, and Russia. The geographical distribution of I. persulcatus is consistent with that of B. divergens in sika deer in Japan. These results suggest that I. persulcatus is a principal vector for B. divergens in Japan and Eurasia, where I. persulcatus is predominantly distributed.IMPORTANCE The Babesiadivergens Asia lineage of parasites closely related to B. divergens in Europe and Babesia sp. MO1 in the United States was recently reported in Cervus nippon in eastern Japan. In this study, specific PCR for the Asia lineage identified 11 positives in 822 host-seeking Ixodes persulcatus ticks, a principal vector for many tick-borne disease agents. Gene sequences of three isolates obtained from DNA in salivary glands of female ticks were identical to each other and to those in C. nippon We also demonstrate the coinfection of B. divergens Asia lineage with Babesia microti U.S. lineage in a tick salivary gland and, furthermore, isolated the latter in a hamster. These results suggest that I. persulcatus is the principal vector for B. divergens as well as for B. microti, and both parasites may be occasionally cotransmitted by I. persulcatus This report will be important for public health, since infection may occur through transfusion.

Molecular identification and characterization of piroplasm species in Hokkaido sika deer (Cervus nippon yesoensis), Japan

Babesia and Theileria species are tick-borne protozoan parasites that have a veterinary and zoonotic importance. In order to investigate the prevalence and genetic diversity of these parasites, a total of 269 sika deer blood DNA samples collected from Hokkaido, Japan, were examined for Babesia and Theileria species by touch-down PCR targeting the 18S rRNA gene. Reverse line blot (RLB) hybridization was then used to detect 12 piroplasm species. The results revealed that 95.5% (257/269), 94.1% (253/269), 14.1% (38/269), 87.7% (236/269) and 11.5% (31/269) of the examined PCR products hybridized with the probes which were designed to detect all Babesia and Theileria spp., all Theileria spp., all Babesia spp., Theileria sp. Thrivae and Babesia divergens-like, respectively. The 18S rRNA gene partial sequences were divided into Theileria sp. Thrivae, T. capreoli, B. divergens-like and an undescribed Babesia species. This study showed the first detection of the undescribed Babesia sp. from Japan. Therefore, more studies are required to understand the ecology of the newly detected tick-borne pathogens in Hokkaido.

Detection and molecular characterization of Babesia, Theileria, and Hepatozoon species in hard ticks collected from Kagoshima, the southern region in Japan

To reveal the distribution of tick-borne parasites, we established a novel nested polymerase chain reaction (PCR) system to detect the most common agents of tick-borne parasitic diseases, namely Babesia, Theileria, and Hepatozoon parasites. We collected host-seeking or animal-feeding ticks in Kagoshima Prefecture, the southernmost region of Kyusyu Island in southwestern Japan. Twenty of the total of 776 tick samples displayed a specific band of the appropriate size (approximately 1.4-1.6kbp) for the 18S rRNA genes in the novel nested PCR (20/776: 2.58%). These PCR products have individual sequences of Babesia spp. (from 8 ticks), Theileria spp. (from 9 ticks: one tick sample including at least two Theileria spp. sequences), and Hepatozoon spp. (from 3 ticks). Phylogenetic analyses revealed that these sequences were close to those of undescribed Babesia spp. detected in feral raccoons in Japan (5 sequences; 3 sequences being identical), Babesia gibsoni-like parasites detected in pigs in China (3 sequences; all sequences being identical), Theileria spp. detected in sika deer in Japan and China (10 sequences; 2 sequences being identical), Hepatozoon canis (one sequence), and Hepatozoon spp. detected in Japanese martens in Japan (two sequences). In summary, we showed that various tick-borne parasites exist in Kagoshima, the southern region in Japan by using the novel nested PCR system. These including undescribed species such as Babesia gibsoni-like parasites previously detected in pigs in China. Importantly, our results revealed new combinations of ticks and protozoan parasites in southern Japan. The results of this study will aid in the recognition of potential parasitic animal diseases caused by tick-borne parasites.

Molecular detection and identification of piroplasms in sika deer (Cervus nippon) from Jilin Province, China

Background

Piroplasmosis is an important disease of domestic animals and wildlife and is caused by organisms from the genera Theileria and Babesia. Wildlife such as sika deer play an important role as reservoir hosts for several species of Theileria and Babesia. Using blood samples collected from sika deer, we investigated the epidemiology of Theileria spp. and Babesia spp. in sika deer from Jilin Province in China and identified those species that cause pathogenic infections in sika deer.

Methods

Sixty-eight blood samples of sika deer were collected from three areas of the Jilin Province in Northeast China. Genomic DNA was extracted, and the V4 hypervariable region of the 18S rRNA of the piroplasms was amplified using the nested PCR method. The selected positive samples were sequenced to identify species of Babesia and Theileria.

Results

PCR detection revealed that 24 samples were positive for Theileria and Babesia spp. (35.29 %, 95 % CI = 11.8-46.8). After alignment, a sequenced fragment for Theileria cervi was found to be the most prevalent from the obtained samples (22.06 %, 95 % CI = 11.8-49.6). Six sika deer samples were identified as being infected with a Theileria sp. that was similar to a Theileria sp. found from spotted deer in India. In addition to the results above, for the first time, we identified T. annulata infection from one sample of sika deer and Babesia sp. from two samples, which showed high identity with Babesia motasi found in sheep from China.

Conclusion

The present study offers new data on the pathogens of piroplasmosis in sika deer in northeastern China. For the first time, sika deer was confirmed as a reservoir host for the T. annulata of cattle and the B. motasi of sheep, which was found in China.

Report of Theileria luwenshuni and Theileria sp. RSR from cervids in Gansu, China

Theileria parasites are important tick-borne pathogens of animals and cause huge economic losses worldwide. Here, we undertook to assess the prevalence of Theileria spp. in cervids in Gansu, China, based on PCR analysis and sequencing of the 18S rRNA genes. Molecular survey showed that Theileria luwenshuni and Theileria sp. RSR were frequently found in Gansu cervids, and the prevalence of T. luwenshuni was 66.7% (n = 9, 6/9) in roe deer in Zhengning County, 58.3% (n = 12, 7/12) in sika deer in Ningxian County, 50% (n = 10, 5/10) in sika deer and 42.9% (n = 14, 6/14) in red deer in Weiyuan County. The prevalence of Theileria sp. RSR was 77.8% (n = 9, 7/9) in roe deer in Zhengning County, 75% (n = 12, 9/12) in sika deer in Ningxian County, 60.0% (n = 10, 6/10) in sika deer, and 50.0% (n = 14, 7/14) in red deer in Weiyuan County. The co-prevalence of the two T. luwenshuni and Theileria sp. RSR was 55.6% (n = 5, 5/9) in roe deer in Zhengning County, 50% (n = 12, 6/12) in sika deer in Ningxian county, 50% (n = 10, 5/10) in sika deer and 35.7% (n = 14, 5/14) in red deer in Weiyuan County, respectively. No other Theileria species was found in these samples. T. luwenshuni and Theileria sp. RSR were detected for the first time in cervids in Gansu, China. Animal experiments showed that four sheep were inoculated with roe deer blood from Zhengning, sika deer blood from Ningxian, sika deer blood, and red deer blood from Weiyuan, respectively, and the Theileria isolated from these inoculated sheep was identified as T. luwenshuni, but Theileria sp. RSR was not detected in these sheep. Our results extend our understanding of the epidemiology of cervine theileriosis in Gansu, China, and will facilitate the implementation of measures to control theileriosis in cervids and small ruminants. This was the first report to demonstrate the occurrence of T. luwenshuni from roe deer, sika deer, and red deer worldwide.

Molecular evidence for piroplasms in wild Reeves' muntjac (Muntiacus reevesi) in China

DNA from liver samples of 17 free-ranging wild Reeves' muntjac (Muntiacus reevesi) was used for PCR amplification of piropalsm 18S rRNA gene. Of 17 samples, 14 (82.4%) showed a specific PCR product which were cloned and sequenced. BLAST analysis of the sequences obtained showed similarities to Babesia sp., Theileria capreoli, Theileria uilenbergi and Theileria sp. BO302-SE. Phylogenetic analysis showed that the Babesia sp. detected in the present study was distantly separated from known Babesia species of wild and domestic animals. Six sequences showed 100% similarity to T. capreoli while five sequences were separated from all known Theileria species and constituted an independent clade with Theileria sp. BO302-SE derived from roe deer in Italy; two sequences were close to T. uilenbergi with 97% similarity. This is the first description of hemoparasite infection in free-ranging wild Reeves' muntjac in China. Our results indicate that wild Reeves' muntjac may play an important reservoir role for hemoparasites.

Molecular identification of Theileria parasites of northwestern Chinese Cervidae

BACKGROUND

Theileria and Babesia protozoan parasites are transmitted mainly by tick vectors. These parasites cause heavy economic losses to the live-stock industry, as well as affecting the health of wild animals in parasite-endemic areas. Identification of infectious agents in wild animals is not only crucial for species preservation, but also provides valuable information on parasite epidemiology. Here, we conducted a molecular surveillance study in Northwestern China to assess the prevalence of blood pathogens in cervids.

METHODS

PCR analysis and microscopic evaluation of blood smears to detect Theileria- and Babesia-related diseases in Cervidae were conducted, in which 22 blood samples from red deer (n = 22) in Qilian Mountain and 20 from sika deer (n = 20) in Long Mountain were collected and tested for the presence of Theileria and Babesia. The 18S rRNA gene was amplified, and selected polymerase chain reaction (PCR)-positive samples were sequenced for species identification.

RESULTS

PCR revealed that 9.1% of the Qilian Mountain samples and 20% of the Long Mountain samples were positive for Theileria uilenbergi; 90.09% of the Qilian Mountain samples (n = 22) were positive for T. capreoli, but all of the Long Mountain samples (n = 20) were negative for T. capreoli; no other Theileria or Babesia species were found. PCR showed that T. uilenbergi and T. capreoli were present in red deer in Qilian Mountain, while only T. uilenbergi was found in sika Deer in Long Mountain. The 18S rRNA gene sequences were aligned against the corresponding GenBank sequences of known isolates of Theileria and Babesia and subjected to phylogenetic analysis. The phylogenetic tree showed that the newly isolated Theileria spp. could be classified as belonging to two clades: one group belonged to the same clade as T. uilenbergi, the other to a clade containing T. capreoli.

CONCLUSIONS

Our results provide important data to increase understanding of the epidemiology of Cervidae theileriosis, and will assist with the implementation of measures to control theileriosis transmission to Cervidae and small ruminants in central China.

Higher sika deer density is associated with higher local abundance of Haemaphysalis longicornis nymphs and adults but not larvae in central Japan

Haemaphysalis longicornis (Acari: Ixodidae) is one of the most common and important arthropod disease vectors in Japan, carrying Japanese spotted fever and bovine theileriosis. The recent expansion of sika deer (Cervus nippon, Artiodactyla: Cervidae) populations, the most common wild host of H. longicornis, has also caused concern about increasing the risk of vector-borne diseases in Japan. We used generalized linear mixed model analysis to determine the relative contribution of deer density and other biological and abiotic factors on the abundance of H. longicornis ticks questing at each developmental stage. A total of 6223 H. longicornis adults, nymphs, and larvae were collected from 70 sites in three regions of central Japan. The abundance of questing adult and nymphal ticks was associated with deer density and other biotic and abiotic factors. However, the abundance of questing larvae showed no association with deer density but did show an association with other biotic and abiotic factors. These findings show that a high density of deer along with other biotic and abiotic factors is associated with increased risk of vector-borne diseases through amplified local abundance of questing nymphal and adult H. longicornis. Further, questing larvae abundance is likely regulated by environmental conditions and is likely correlated with survival potential or the distribution of other host species.

Theileriosis in a reindeer (Rangifer tarandus tarandus) associated with a potentially novel Theileria sp

A 5-year-old male neutered reindeer (Rangifer tarandus tarandus) from Missouri was presented with a 3-week history of anorexia, respiratory distress, lethargy, and weight loss. Blood smear review revealed that a small percentage of RBCs contained small (1-2 μm in length) pleomorphic piroplasms (signet ring, rod- or pear-shaped, and elongate forms) with an eccentric magenta nucleus and basophilic cytoplasm. Nested PCR to specifically amplify a portion of the piroplasm small subunit ribosomal RNA (SSU rRNA) gene was performed on DNA extracted from an EDTA specimen of whole blood. Subsequent sequence analyses showed similarity between the reindeer hemoparasite and Theileria spp SSU rRNA gene sequences in the GenBank database, with highest similarity to those of a Theileria sp in a White-tailed deer from North Texas (AY735132, AY735133). The reindeer and North Texas Theileria sp are genetically distinct from, albeit closely related to, the White-tailed deer Theileria sp (subsequently referred to as T cervi). To the authors' knowledge, this is the first identification of Theileria of this genotype in a reindeer. Historically, T tarandirangiferis infection was found with associated mortality in reindeer in Russia, but reports predate molecular characterization. Hence, the relationship of T tarandirangiferis with either T cervi or this agent remains unknown. T cervi is not typically pathogenic in White-tailed deer in the US unless the animal is immune-compromised by stress or disease; however, mortality from T cervi infection in reindeer has been reported.

Molecular phylogenetic analysis of Theileria species detected from Japanese serows (Capricornis crispus) in Iwate Prefecture, Japan

In the present study, we tried to detect DNA for ribosomal RNA genes of piroplasma parasites from the liver or blood of 43 Japanese serows (Capricornis crispus) in Iwate Prefecture of Japan by polymerase chain reaction. Approximately 500-bp amplicons were obtained in 35 (81.4%) of the 43 samples by amplification for V4 hyper-variable regions of the 18S rRNA gene, and the amplicons were considered to be DNA of Theileria species. The complete nucleotide sequences (1,700 or 1709 bp) of the 18S rRNA gene were determined in 20 samples and were divided into 5 genotypes that were phylogenetically separated into two different lineages showing a polyphyletic relation. The Theileria DNAs of the two different lineages were considered to be those of distinct species.

Detection of Theileria and Babesia in brown brocket deer (Mazama gouazoubira) and marsh deer (Blastocerus dichotomus) in the State of Minas Gerais, Brazil

Intraerythrocytic protozoan species of the genera Theileria and Babesia are known to infect both wild and domestic animals, and both are transmitted by hard-ticks of the family Ixodidae. The prevalences of hemoprotozoa and ectoparasites in 15 free-living Mazama gouazoubira, two captive M. gouazoubira and four captive Blastocerus dichotomus from the State of Minas Gerais, Brazil, have been determined through the examination of blood smears and the use of nested polymerase chain reaction (nPCR). The cervid population was inspected for the presence of ticks and any specimens encountered were identified alive under the stereomicroscope. Blood samples were collected from all 21 animals, following which blood smears were prepared, subjected to quick Romanowsky staining and examined under the optical microscope. DNA was extracted with the aid of commercial kits from cervid blood samples and from tick salivary glands. The nPCR assay comprised two amplification reactions: the first was conducted using primers specific for a 1700 bp segment of the 18S rRNA gene of Babesia and Theileria species, whilst the second employed primers designed to amplify a common 420 bp Babesia 18S rRNA fragment identified by aligning sequences from Babesia spp. available at GenBank. The ticks Amblyomma cajennense, Rhipicephalus microplus and Dermacentor nitens were identified in various of the cervids examined. Of the animals investigated, 71.4% (15/21) were infected with hemoprotozoa, including Theileria cervi (47.6%), Theileria sp. (14.3%), Babesia bovis (4.8%) and Babesia bigemina (4.8%). However, only one of the infected wild cervids exhibited accentuated anaemia (PCV=17%). This is first report concerning the occurrence of Theileria spp. in Brazilian cervids.

Molecular phylogenetic studies on Theileria spp. isolates (China) based on small subunit ribosomal RNA gene sequences

Six Theileria spp. from cattle, buffalo and black goat were identified in the Hubei province of China. In order to study the taxonomic status of these parasites, phylogenetic analysis of 18S rRNA genes were carried out. The 18S rRNA genes from each isolate were amplified by the polymerase chain reaction and the approximate 1.75 kb products were cloned and sequenced. Phylogenetic analysis of these gene sequences revealed that the five parasites from buffalo and cattle belonged to the Theileria sergenti/buffeli/orientalis group. The parasite from the Chinese goat (Macheng-Hubei, DQ286802) was closely related to Theileria luwenshuni isolated from sheep in the north of China. This represent the first report on the use of molecular phylogeny to classify Theileria spp. obtained in the Hubei province, showing that Theileria spp. from ruminants found in Hubei province belongs to the benign group of Theileria spp.

Molecular detection and characterization of piroplasms infecting cervids and chamois in Northern Spain

Wildlife can act as reservoir of different tick-borne pathogens of veterinary and zoonotic importance. To investigate the role of wild ruminants as reservoir of piroplasm infection, 28 red deer, 69 roe deer and 38 chamois from Northern Spain were examined by reverse line blot (RLB) hybridization. The survey detected a prevalence of 85.7% in red deer, 62.3% in roe deer and 28.9% in chamois. Four different piroplasms were identified: Theileria sp. OT3 (previously described in sheep) as the most prevalent (85.7% in red deer, 46.4% in roe deer and 26.3% in chamois); Theileria sp. 3185/02 (previously described in a red deer in Central Spain) more abundant in red deer (53.6%) than in roe deer (10.1%) but absent from chamois; Babesia divergens detected in 6 roe deer; Theileria ovis present in 1 chamois. Mixed infections (Theileria sp. OT3 and Theileria sp. 3185/02) were only found in red and roe deer. Sequencing analysis of the 18S rRNA gene confirmed the RLB results and showed 99.7% identity between Theileria sp. 3185/02 and T. capreoli, suggesting that they are the same species. Tick distribution and contact of wild ruminants with domestic animals are discussed in terms of piroplasm infection. The results suggest that a considerable number of wildlife ruminants are asymptomatic carriers that may serve as reservoirs of the infection posing a serious concern in terms of piroplasmosis control.