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1.
In a series of experiments, sporozoite stabilates of a Theileria lestoquardi (Lahr) and a T. annulata (Ankara) stock prepared from Hyalomma anatolicum anatolicum ticks, were used to examine the infectivity of both parasite species for sheep and cattle and to study the development of cross-immunity between these parasite species. In the first experiment sheep and cattle were inoculated with T. lestoquardi sporozoites. Surviving animals and naive sheep and cattle were, in the second experiment, inoculated with T. annulata. In the third experiment, naive sheep and sheep previously infected with T. annulata, were inoculated with T. lestoquardi. The following responses to inoculations were monitored: clinical and haematological signs of infection, appearance of parasitic stages of the parasites in lymph node biopsies and in peripheral blood and serological response to T. lestoquardi and T. annulata schizont antigens. While T. lestoquardi readily infected sheep and caused severe disease, it did not infect cattle. On the other hand, T. annulata infected both cattle and sheep. However, whereas cattle became severely affected, infected sheep showed mild clinical symptoms only and piroplasms did not develop. Despite their different behaviour in the host species examined, cross-immunity studies suggested that the parasite species are very closely related. Experiments in sheep indicated that T. lestoquardi infection protected against subsequent T. annulata infection. On the other hand, recovery from T. annulata infection did not prevent infection by sporozoites of T. lestoquardi, resulting in the establishment of schizonts and their subsequent development into piroplasms, although it protected against the major clinical effects of T. lestoquardi infection. 相似文献
2.
M Kachani R A Oliver C G Brown H Ouhelli R L Spooner 《Veterinary immunology and immunopathology》1992,34(3-4):221-234
Western blot analysis of Theileria annulata antigens was carried out using sera collected from cattle which had been immunised and challenged with either T. annulata sporozoites or schizont-infected cells. Three antigens between 71 and 73 kDa proved to be common to the three stages of parasite studied: sporozoites, schizonts and piroplasms. An antigen was found at 32 kDa which was specific to T. annulata piroplasms. Results were reproducible using sera from Morocco and the UK. At least one of the proteins at 71-73 kDa, but not that at 32 kDa were also recognised by sera from animals infected with Babesia species. 相似文献
3.
C M Rubaire-Akiiki 《Veterinary parasitology》1990,34(4):273-288
Two Bos taurus calves were made resistant to tick infestation by exposing them to approximately 500 rabbit-reared nymphs of Hyalomma anatolicum anatolicum twice at a 2-week interval. These two calves, together with a tick-susceptible control calf, were inoculated with a stabilate of Theileria annulata (Ankara). Patent infection resulted in all three calves. Seven-hundred and fifty gerbil-reared nymphs were then applied on each of these calves as well as another tick-susceptible calf that was Theileria free. This infestation was carried out on Day 8 post-inoculation. Ticks that dropped on Day 13 post-inoculation were examined to note the development of T. annulata in them and the histological changes that occurred in the gut and salivary glands. During the second phase of feeding, the gut epithelia of the ticks from the tick-resistant calves were less active. There were no notable differences in the characteristics of the developmental stages of T. annulata between the ticks from the tick-resistant calves and those from the susceptible calf. However, ticks from one calf that acquired a higher level of tick resistance were significantly less susceptible to infection by T. annulata. Bovine tick resistance therefore compromises the vector capacity of H. a. anatolicum and this may be of epidemiological significance in the endemic areas of tropical theileriosis. 相似文献
4.
Groups of Theileria annulata infected Hyalomma anatolicum anatolicum adults prefed on a calf for 1 to 6 days were separately ground in tissue culture medium-199, supplemented with bovine albumin powder, Fraction-V. Supernatant fluid was collected, made up with additional medium, so that each millilitre represented material from 25 ticks, and was injected subcutaneously into groups of cross-bred male calves. The results indicated that ground-up tick supernate (GUTS) prepared from unfed ticks was not infective, whereas that prepared from 1 to 6 days prefed ticks was infective. GUTS prepared from 3 days prefed ticks appeared to contain highest infectivity and 1 ml of it induced fatal theileriosis. 相似文献
5.
Dumanli N Aktas M Cetinkaya B Cakmak A Koroglu E Saki CE Erdogmus Z Nalbantoglu S Ongor H Simşek S Karahan M Altay K 《Veterinary parasitology》2005,127(1):9-15
This study was carried out to determine the prevalence and distribution of tropical theileriosis in cattle in eastern Turkey by microscopical, serological and molecular methods. A total of 1561 whole blood, 1505 serum and 1483 blood smear samples were collected from cattle of various breeds and ages in 11 towns of Eastern Turkey. Theileria annulata piroplasm DNA extracted from cattle blood was amplified by polymerase chain reaction (PCR) using species-specific primers. Serum antibodies against T. annulata were investigated by indirect fluorescence antibody test (IFAT). Blood smears were examined for Theileria piroplasms by microscopical examination (ME). In the examination of DNA extracted from 1561 blood samples, an amplicon with the size of 721bp was obtained in 37.8% (590/1561) of these samples. Serum antibodies against T. annulata and piroplasm of Theileria spp. were detected in 34.9% (526/1505) and 19.7% (293/1483) of the samples, respectively. The differences between ME and PCR results and between ME and IFAT results were statistically significant (P < 0.05). In contrast, there was no significant difference between the PCR and IFAT results. A total of 179 ticks (136 female; 43 male) belonging to Hyalomma spp. were collected from cattle from three towns. Ticks were identified to be Hyalomma anatolicum anatolicum on the basis of morphological features. 相似文献
6.
In an attempt to develop vaccine against Hyalomma anatolicum anatolicum and Theileria annulata, three antigens were expressed in prokaryotic expression system and protective potentiality of the antigens was evaluated in cross bred calves. Two groups (grs. 1 and 4) of male cross-bred (Bos indicus × Bos taurus) calves were immunized with rHaa86, a Bm86 ortholog of H. a. anatolicum, while one group of calves (gr. 2) were immunized with cocktails of two antigens viz., surface antigens of T. annulata (rSPAG1, rTaSP). One group each was kept as negative controls (grs. 3 and 5). The animals of groups 1, 2 and 3 were challenged with T. annulata infected H. a. anatolicum adults while the animals of groups 1, 3, 4 and 5 were challenged with uninfected adult ticks. A significantly high (p<0.05) antibody responses to all the three antigens were detected in immunized calves, but the immune response was comparatively higher with rHaa86 followed by rTaSP and rSPAG1. Upon challenge with T. annulata infected ticks, animals of all groups showed symptoms of the disease but there was 50% survival of calves of group 1 while all non immunized control calves (group 3) and rSPAG1+rTaSP immunized calves died. The rHaa86 antigen was found efficacious to protect calves against more than 71.4-75.5% of the challenge infestation. The experiment has given a significant clue towards the development of rHaa86 based vaccine against both H. a. anatolicum and T. annulata. 相似文献
7.
Shkap V Pipano E Rasulov I Azimov D Savitsky I Fish L Krigel Y Leibovitch B 《Veterinary parasitology》2003,115(3):247-255
A field isolate of Theileria annulata (Uzbek strain) was obtained from calves infected by Hyalomma anatolicum ticks collected from an endemic region in Uzbekistan. Schizont-infected bovine cells that had been established and propagated in cell culture were examined for attenuation both in vivo, by inoculating cells from various passages into calves, and in vitro for metalloproteinase activity. During serial subcultivation a gradual reduction in virulence and in enzyme activity in cells infected with the Uzbek strain were observed. Complete attenuation of the Uzbek isolate was obtained at about passage 80, and only traces of proteolysis were detected in gelatin substrate gels. In contrast, there was no direct correlation between virulence and enzyme levels in an Israeli strain. While schizonts of the Israeli strain were completely attenuated at passage 80, proteolysis in the substrate gels was detected up to passage 197. Solid immunity was observed in calves immunized with attenuated T. annulata schizonts of the Uzbek strain upon challenge with the homologous H. excavatum sporozoites. For a strain to be used for vaccine production, it appears that animal inoculation still remains the most reliable method to assess the degree of attenuation and protection. 相似文献
8.
A survey of Theileria parasites in cattle in eastern Turkey was carried out using specific polymerase chain reaction. A total of 252 blood samples were collected from clinically healthy cattle between June and July 2004. Of 252 blood samples examined, 41 (16%) were positive for piroplasms by microscopy, whereas 114 (45%) were positive for the presence of at least one species of Theileria by PCR. The percentages of positive animals for Theileria annulata and benign Theileria species (Theileria sergenti/buffeli/orientalis) were 39% (99/252) and 7% (18/252), respectively. By allele-specific PCR examination of 18 field isolates which were positive for benign Theileria parasites, 8 samples were only amplified by B-type specific primers and 10 samples were amplified by both of the B and C-type specific primers, indicating a mixed infection with B and C-type of the parasite. None of the field isolates was amplified by I-type specific primers. Three samples were co-infected with T. annulata and benign Theileria parasites. Two of them which were infected with B-type parasite were also infected with T. annulata, the other sample which was infected both of B and C-type parasites was also infected with T. annulata. A total of 724 ixodid ticks were collected from the cattle. Hyalomma anatolicum anatolicum was the dominant species with 32% (230/724) in the region. H. a. excavatum, Boophylus annulatus and Rhipicephalus bursa represented 25% (183/724), 19% (140/724) and 15% (112/724) of the total number of ticks, respectively. R. sanguineus was the minor species and represented 8% (59/724) of the tick population. 相似文献
9.
利用蜱传播试验确定小亚璃眼蜱对中国新分离的牛的巴贝斯虫未定种和环形泰勒虫的传播能力与传播方式，进而明确其在中国牛梨形虫病传播中的流行病学意义。试验结果表明：小亚璃眼蜱可在雌虫阶段受到巴贝斯虫未定种的感染，并可在次代若虫（2／2）和成虫（3／3）阶段将病原传播给试验牛；小亚璃眼蜱幼虫和若虫吸入环形泰勒虫，饱血脱落的幼虫和若虫所蜕化发育的饥饿若虫（2／2）和成虫（2／2）均可将病原传递给敏感动物；感染巴贝斯虫未定种的小亚璃眼蜱饱血雌虫所孵育出的次代幼虫和若虫仍可被环形泰勒虫感染，所发育出的若虫（2／2）和成虫（2／2）可在一次传播试验中将环形泰勒虫和巴贝斯虫未定种同时传播给试验动物。 相似文献
10.
Marc Govaerts Peter Verhaert Frans Jongejan Bruno M Goddeeris 《Veterinary parasitology》2002,104(2):103-117
The immunodominant 33/35kDa antigen of a Theileria isolate from West Java, Indonesia, was characterised and immuno-affinity purified by use of a monoclonal antibody, KUL-a4, and was shown to be representative of the T. orientalis/sergenti/buffeli group. The aminoterminal sequence of the purified 35kDa peptide (20 residues) was determined by automated Edman degradation and found to correspond to the predicted amino acid sequence of a prospective p33 gene previously sequenced from the same isolate. The cleavage site of a putative signal peptide was identified and conforms the (-3, -1) rule for signal peptidases. The existence of dimeric and trimeric forms of the p33/35 antigen is hypothesised from Western blot profiles. KUL-a4 appeared specific for the T. orientalis/sergenti/buffeli group. It did not recognise in indirect fluorescence antibody test (IFAT), intraerythrocytic bodies of Anaplasma marginale or piroplasms and schizonts of T. mutans, T. parva and T. annulata, whereas cattle antisera raised to these species showed cross-reactivity in IFAT. It however, appeared weakly cross-reactive in Western blot and ELISA, with the 34kDa piroplasm antigen of one T. annulata (Gharb) isolate. The present study indicates that the isolated antigen belongs to the p33/34 antigen family described within the T. sergenti/orientalis/buffeli group, and documents the group-specificity of one of its epitopes. 相似文献
11.
Sayin F Karaer Z Dincer S Cakmak A Inci A Yukari BA Eren H Vatansever Z Nalbantoglu S Melrose TR 《Veterinary parasitology》2003,113(2):115-121
In this comparative study unfed nymphs of four Hyalomma tick species (Hyalomma anatolicum anatolicum, Hyalomma anatolicum excavatum, Hyalomma detritum and Hyalomma marginatum marginatum) were allowed to engorge on calves experimentally infected with Theileria annulata. The infection prevalence in the salivary glands of the adult female and male ticks of each Hyalomma species used in the study were assessed. The infection prevalence with T. annulata was high and did not vary markedly in the four Hyalomma tick species. The mean number of infected acini per tick in female and male ticks was different with female ticks having higher numbers of infected acini than the male ticks. The sex difference was more significant between H.a. anatolicum and H.a. excavatum than between H. detritum and H.m. marginatum. This study clarifies the roles of four Hyalomma tick species, and their sex, in the development of T. annulata. 相似文献
12.
Blood from calves infected with Theileria annulata and T parva was freed from host cell elements and the piroplasms liberated from the red cells by ammonium chloride lysis. Lysates of the purified piroplasms and control host cell material were examined electrophoretically for several enzymes. Zymograms stained for glucose phosphate isomerase showed distinct differences between the host cell enzyme pattern and parasite enzyme patterns. The isoenzyme pattern of T annulata piroplasms differed from the isoenzyme pattern of T parva piroplasms. 相似文献
13.
Immunization of cattle with nymphal Hyalomma anatolicum anatolicum extracts: effects on tick biology
Antigens derived from partially engorged nymphs of Hyalomma anatolicum anatolicum were used in immunizing crossbred (Bos indicus×Bos taurus) cattle against larval, nymphal and adult H. a. anatolicum and H. dromedarii. The cattle were either infected with Theileria annulata at low parasitaemia or were uninfected. Whole nymphal extract (WNE), nymphal membrane antigens (NMA) and nymphal soluble antigens (NSA) were used for immunization. The group immunized with WNE showed significant and better rejection of H. a. anatolicum ticks as compared to calves immunized with either NMA or NSA. The moulting rates of both engorged larvae and nymphs remained unaffected. Nymphs which engorged on the immunized calves were fully susceptible to infection by T. annulata as indicated by the intensity and abundance of Theileria infections in the resulting adult ticks from immunized and unimmunized Theileria infected cattle. These ticks also transmitted fatal theileriosis to susceptible calves. 相似文献
14.
The effects of experimental Theileria annulata infection on the i.m. (20 mg/kg) pharmacokinetics of oxytetracycline were investigated in crossbred calves. The serum concentration-time curves of oxytetracycline (OTC-LA), before and after experimental infection, were best described by a one-compartment open model. The experimental infection by subcutaneous administration of ground-up tick supernate (GUTS), equivalent to 30 Hyalomma anatolicum anatolicum ticks infected with Theileria annulata, produced a clear temperature rise and signs of clinical disease in calves. Subsequently, haemoglobin, packed cell volume, total leucocyte count and serum Cu, Fe and Zn concentrations decreased after infection. The absorption and elimination half-lives (t1/2 Ka and t1/2 Ke), mean absorbance time (MAT), time to peak concentration (Tmax), mean residence time (MRT), area under the serum concentration time curve (AUC infinity) and the bioavailability (F) were significantly (P < 0.05) decreased. The peak serum concentration (Cmax), however, remained unchanged after infection. These changes may necessitate alterations in the dosage regimen of oxytetracycline used to treat Theileria annulata infections in cattle under field conditions. 相似文献
15.
Hyalomma anatolicum anatolicum ticks were collected around cattle pens at two locations close to Khartoum. They were assessed for theileria infection by four methods. Salivary glands were stained whole with methyl green pyronin and examined for parasite masses. Adult ticks were partially fed on rabbits, ground up in medium, and the suspensions were examined in Giemsa stained smears and by inoculation into bovine lymphocyte cultures. Ticks were fully fed on calves which were monitored for developing theileriosis. H a anatolicum were found infected with parasite masses similar to those seen in experimental infections with T annulata. At one site 38 per cent of 102 ticks were infected and the mean number of parasite masses per tick for the whole sample was 37. At the other site 86 per cent of 156 ticks were similarly infected and the mean parasite masses per tick was 19.5. Suspensions of sporozoites contained sporozoites typical of those found in experimental preparations of T annulata. Sporozoites harvested from ticks from both locations infected and transformed normal bovine lymphocyte cultures. H a anatolicum ticks from both locations produced fatal theileria infection in susceptible calves. 相似文献
16.
Twenty cross-bred (Bos taurus X Bos indicus) calves, 7-21 days old, were infected by a ground-up tick supernate of Hyalomma anatolicum anatolicum infected with the Hisar isolate of Theileria annulata. Six calves acted as untreated controls and they all died of theileriosis within 17 days of infection. The remaining 14 calves were divided into Group A and B, each consisting of seven calves. All the calves of Groups A and B were treated intramuscularly with buparvaquone (BW 720C) on Day 11 post-infection, when clinical signs of theileriosis were apparent. Each calf received 2.5 mg BW 720 C kg-1 body weight as a single injection. In addition, each calf of Group B was given proprietary haematinics by intramuscular injection, daily for 12 days. In Group A, two calves died of cerebral theileriosis and five were clinically cured. However, four of these five calves later died of anaemia. In Group B, all the calves were clinically cured and none died during the observation period of 1 month. The parasitaemia declined to less than 1% within a fortnight of treatment. The initial declines in haemoglobin concentration and packed cell volume were halted and preinfection values were soon restored. No toxic signs attributable to treatment with buparvaquone were observed. 相似文献
17.
Adhesion to target cells is an essential step in the pathogenesis of many protozoal infections. Some protozoa have been reported to have a lectin activity involved in their attachment to the cell surface. The ligand-receptor interaction involved in Theileria annulata infection is unclear at present, in spite of the fact that some aspects of the process have been investigated. To this end, T. annulata piroplasms have been screened for lectin activity. Blood taken from infected cattle was first depleted of leukocytes and then subjected to ammonium chloride lysis in order to isolate the piroplasms. The piroplasms were homogenised and a crude membrane extract was prepared by centrifugation. To investigate lectin activity in piroplasm proteins, a simple screening procedure was employed for analysing piroplasm proteins binding to various lectin ligands. Numerous immobilised lectin ligands (L-fucose-sepharose, N-acetyl-neuraminic acid-sepharose, N-acetyl-D-galactosamine-agarose, N-acetyl-D-glucosamine-agarose, D-mannose-agarose, beta-D-glucose-agarose, alpha-methyl-D-mannoside-agarose) were incubated with T. annulata piroplasm crude membrane extract. The ligand-bound proteins were eluted and separated by a brief centrifugation and determined by sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE). The present study suggests that a 32 kDa protein of piroplasm binds to D-galactosyl residues of the agarose matrix and that the binding is inhibited by galactose and not by the other monosaccharides tested. 相似文献
18.
The existence of metabolic energy pathways has been studied in extracellular T. annulata sporozoites using chemicals known to inhibit specific energy-generating pathways, and their role during invasion of bovine peripheral blood lymphocytes (PBL) by the sporozoites determined in an in vitro system. An inverse relationship was depicted between the dose of various chemicals and the number of T. annulata sporozoites invading PBL: as the concentrations of the inhibitor drugs increased, the number of T. annulata sporozoites within the lymphocytes decreased. An ultracytochemical study demonstrated the presence of the respective pathway marker enzymes, i.e., lactic dehydrogenase (LDH) in the cytosol and within mitochondria, succinic dehydrogenase (SDH) on the mitochondrial membranes and in the contiguous matrix, and cytochrome oxidase (CO) between the inner and outer mitochondrial membranes, in infective T. annulata sporozoites fixed in situ within whole salivary glands of 3-day fed Hyalomma anatolicum anatolicum ticks. 相似文献
19.
G S Miranpuri 《Veterinary parasitology》1986,22(1-2):9-19
Rabbits immunized with purified sporozoites from Hyalomma anatolicum anatolicum produced antibody to Theileria annulata specific antigens as measured by the indirect fluorescent antibody test. Nonspecific fluorescence which compounded the interpretation of the test was observed. Incorporation of Eriochrome black and Evans blue as a counterstain in the diluent buffer for the conjugate significantly reduced the background fluorescence. 相似文献
20.
Hyalomma anatolicum anatolicum engorged nymphs and flat adults were collected from two areas in northern Sudan. Various developing stages of Trypanosoma theileri-like flagellates were observed in the engorged nymphs, freshly moulted adults and mature adults partially engorged on rabbits. When these ticks were applied to two calves, one calf became infected with the trypanosome. The parasites were observed for one day in the enlarged lymph node nearest to the tick-feeding site 5 days after the tick application. Subsequently the trypanosomes were re-isolated in vitro from the infected calf. Inoculation of a ground-up tick supernatant suspension from the infected batch of ticks containing 10(4) trypanosomes into a calf did not produce a patent infection. 相似文献