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1.
The parthenogenetic Haemaphysalis longicornis larvae engorged on cattle naturally infected with Theileria sergenti were reared at 24 degrees C. The resultant nymphal ticks were incubated at 37 degrees C to clear the effect of incubation on the development and maturation of sporozoites. The sporozoites in the salivary glands of the nymphal ticks exposed to 37 degrees C for 16 days were observed by the methyl green pyronin staining method. The ticks exposed to 37 degrees C were ground up in a mortar and the supernatant of the tick suspension in PBS was inoculated into cattle. The cattle showed parasitemia and specific antibody response 18 days after inoculation. Consequently, the parasites in the tick salivary glands became infective to cattle by incubating infected. H. longicornis nymphs at 37 degrees C.  相似文献   

2.
Lysates prepared from the salivary glands of uninfected Hyalomma anatolicum anatolicum and Rhipicephalus appendiculatus and from ticks of these species infected with 2 strains of Theileria annulata and 1 strain of T. parva respectively have been examined for enzyme polymorphism using thin layer starch gel electrophoresis. Representative enzymes from 3 of the major metabolic pathways, the tricarboxylic acid cycle, the glycolytic pathway and the pentose phosphate pathway were investigated. Only 1 enzyme, glucose phosphate isomerase, showed differences between the host cell activity and the parasite activity and also inter- and intraspecific differences between the parasites. This technique represents a useful complement to the present histochemical methods for identification of Theileria infections in the salivary glands of ticks.  相似文献   

3.
The relative role of male and female Hyalomma anatolicum anatolicum ticks in the epidemiology of Theileria transmission was studied by detecting Theileria sporozoites in the dissected salivary glands of 568 ticks by the methyl green pyronin staining method. Detailed frequency distribution of Theileria-positive acini in the salivary glands of the 264 (46.48%) positive ticks from a field collection in Haryana indicated that the number of infected salivary acini per positive tick was greater in females than in males. This suggests that female ticks have a more important role in Theileria transmission than male ticks. This finding assumes greater significance in the light of the observation that the natural male:female ratio is also in favour of female ticks.  相似文献   

4.
Adult Hyalomma anatolicum anatolicum ticks infected with Theileria annulata (Hissar strain) were incubated at 36 degrees C or fed on rabbits. Tick salivary glands were stained whole with methyl green pyronin or ground up and deposited on microscope slides and stained with Giemsa's solution. Separate batches of ticks from both treatments were ground up, centrifuged and filtered to produce sporozoite suspensions. The suspensions were examined as deposits on microscope slides stained with Giemsa's solution. The Theileria in the salivary glands of the fed ticks matured more completely and rapidly than in the incubated ticks. The peak numbers of sporozoites from the fed ticks was greater by at least tenfold than the peak from the incubated ticks. This peak was on the third day of feeding or on the fourth day of incubation. It was confirmed that fed ticks will be more suitable for sporozoite production for infection of cattle and production of stabilates.  相似文献   

5.
Hyalomma anatolicum anatolicum nymphs were collected from two localities in the Sudan: Eddamer in Northern Sudan and Wad-Medani in Central Sudan. They were allowed to moult to adult ticks, which were assessed for Theileria infection in their salivary glands using Feulgen stain. At Eddamer, 49.6% of 123 ticks examined were infected with Theileria and the mean intensity of infection was 1.3 (i.e. the number of infected acini/number of infected ticks). At Wad-Medani, 8.6% of 162 ticks were infected and the mean intensity of infection was 7.9. The prevalence of infection was higher in female than in male ticks at both localities. When adult H. a. anatolicum were applied onto two susceptible calves, both animals developed the severe form of theileriosis.  相似文献   

6.
Three cattle, which had been experimentally infected with Theileria parva lawrencei and maintained as carriers of the infection, were each infested simultaneously with clean nymphal Rhipicephalus appendiculatus and Rhipicephalus zambeziensis in ear bags on separate ears. After moulting, the ensuing adult ticks were fed on rabbits for 4 days and their salivary glands were examined for infective stages of the parasite. Microscopic examination revealed significantly higher infection rates in the salivary glands of R. zambeziensis than in R. appendiculatus which may indicate an increased vector efficiency of R. zambeziensis for T. p. lawrencei.  相似文献   

7.
A cDNA expression library from the salivary glands of hard tick, Haemaphysalis longicornis, was constructed. Immunoscreening was performed using sera of the rabbit repeatedly infested with ticks and seventeen positive clones were obtained. A BLASTP search suggested that 8 sequences matched with that of hypothetical H. longicornis sequence and one clone encoded HL35 antigen U from the same tick species. Eight of 17 gave no match to any sequence reported in the database. The proteins expected from these novel sequences possess common characteristics with cement proteins which assist ticks in their attachment to the host during blood feeding. The expression of these genes in salivary glands was confirmed by RT-PCR. Four of the 8 sequences showed to be upregulated upon blood feeding. These immunodominant antigens are of particular interest as candidates for future cement protein based-tick vaccine.  相似文献   

8.
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   

9.
The Theileria parva carrier-state in cattle on commercial farms on Zimbabwe was investigated using parasitological and serological methods. The proportion of cattle showing Theileria piroplasms on two farms, which had recent histories of disease outbreaks, were 64% (n = 106, total of heifers and weaned calves examined) and 71.5% (n = 60) while the proportion of T. parva antibodies for the same animals were 59% and 98.5%, respectively. On four farms where no cases of the disease occurred for over 10 years, the average proportion of animals showing piroplasms and antibodies were 55.4% (range 32-82, n = 223) and 73% (range 47-91, n = 223), respectively. However, on another three farms which had no history of theileriosis outbreaks these proportions were very low, being 11.4% (0-24, n = 157) for piroplasms and 12.2% (5-23, n = 157) for antibodies. The mean infection rate in unfed Rhipicephalus appendiculatus adults collected from farms with a high prevalence of cattle which were carriers of Theileria piroplasms during the tick activity season was 29% (range 12-60%) with 9.3 (range 2-18.7) mean infected acini per infected tick. The infectivity of different tick batches to susceptible cattle produced a wide spectrum of theileriosis reactions. Laboratory controlled experiments were carried out to study the persistence of T. parva (Boleni) piroplasms in cattle immunized with this strain as well as its infectivity for ticks and its subsequent transmissibility to cattle. Examination of the salivary glands of 15 batches of ticks collected from six immunized cattle on three different occasions over 18 months showed that none were infected with Theileria parasites. However, the infectivity of other ticks in the same batches to susceptible animals was demonstrated 6, 10 and 18 months after cattle had been immunized with Boleni stabilate.  相似文献   

10.
Seven healthy sheep and 10 sheep diagnosed with piroplasmosis based on clinical signs were tested for the presence of babesiae and theileriae. Using the molecular techniques, two species of theileriae were detected and characterized. Theileria ovis was present mostly in healthy sheep and in Rhipicephalus ticks collected from infected sheep. Theileria sp. OT3 parasite was detected mostly in ill animals which represent additional evidence to the possible pathogenic nature of Theileria sp. OT3. The presence of babesiae in sheep or in ticks was not determined. The results of this study showed that ovine piroplasmosis due to Theileria is present in Southern Croatia. It was concluded that clinical diagnosis of ovine piroplasmosis should be confirmed by molecular analysis in order to identify the species of piroplasm, to select the appropriate treatment and to exclude the threat for public health.  相似文献   

11.
甘肃省部分牛羊血液原虫传播媒介的实验研究   总被引：4，自引：0，他引：4  
利用蜱传播试验,确定了甘肃省一些牛羊血液原虫的媒介和传播方式。甘肃省牛的双芽巴贝斯虫媒介为微小牛蜱。大巴贝斯虫媒介为长角血蜱。瑟氏泰 勒虫媒介为长角血蜱;绵羊无浆体的媒介为草原革蜱。微小牛蜱、长角血蜱可分别传播双芽巴贝斯虫和大巴贝斯虫,传播方式为经卵传递。将采集于甘肃文县牛体上的微小牛蜱和两当县的长角血蜱饱血雌虫孵育而来的次代幼虫分别叮咬除脾牛体后,２头牛各自感染双芽巴贝斯虫或大巴贝斯虫。将采自崇  相似文献   

12.
The ability of PCR to detect infections of Theileria parva, the cause of East Coast Fever, in field-collected tick and bovine samples from Tanzania was evaluated. PCR-detected infection prevalence was high (15/20, 75%) in unfed adult Rhipicephalus appendiculatus ticks that fed as nymphs on an acutely-infected calf, but low (22/836, 2.6%) in unfed adult R. appendiculatus collected from field sites in Tanzania. Tick infection prevalence was comparable to that in previous studies that used salivary gland staining to detect T. parva infection in field-collected host-seeking ticks. Of 282 naturally-exposed zebu calves, seven had PCR-positive buffy coat samples prior to detection of Theileria spp. parasites in stained buffy coat cells or lymph node biopsies. Evidence of Theileria spp. infections was detected in stained smears of lymph node biopsies from 109 calves (38.6%) and buffy coat samples from 81 (28.7%), while buffy coat samples from 66 (23.4%) were PCR-positive for T. parva. Implications of these findings for the sensitivity and specificity of the PCR are discussed.  相似文献   

13.
The effect of temperature on the transtadial transmission of Theileria annulata in Hyalomma anatolicum anatolicum was studied. Variation in temperature (4-40 degrees C) had a significant effect on moulting rate of the ticks and transmission of theilerial parasites from nymphs to resultant adults. The temperatures above 40 degrees C and below 12 degrees C prevented moulting. Maximum infection levels were obtained in salivary glands of adult ticks when the infected engorged nymphs were incubated at 24-28 degrees C. The infection rate in salivary glands was assessed using a methyl green pyronin technique.  相似文献   

14.
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.  相似文献   

15.
A simplified method for methyl green pyronin staining is described for Theileria parva and T. annulata in whole salivary glands of Rhipicephalus appendiculatus and Hyalomma anatolicum subspecies respectively. The stain gives results comparable with Feulgen staining and can be used after the ticks have been in cold storage for 3 days. There is considerable variability in the rate and intensity of infection of these ticks with theilerial parasites and it is concluded that the method permits large samples (60 ticks per person per day) to be examined to overcome this variability when assessing infection quantitatively.  相似文献   

16.
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   

17.
A total of 2388 cattle and 442 shelters, from two provinces (Elazig and Malatya) endemic for tropical theileriosis in the east of Turkey, were studied for Hyalomma tick populations from July 1993 to July 1995 in Elazig and from May 1998 to January 1999 in Malatya. Four thousand five hundred and eighty one of 7455 Hyalomma ticks were collected from cattle, the other ticks (2874) were collected from shelters. All of the ticks collected from shelters were Hyalomma anatolicum anatolicum. Two thousand eight hundred and ninety five (63.1%) of 4581 Hyalomma ticks collected from cattle were H.a. anatolicum. 23.8% (1047/4581), 11.7% (536/4581) and 0.6% (3/4581) of Hyalomma ticks were Hyalomma anatolicum excavatum, Hyalomma detritum and Hyalomma marginatum marginatum, respectively. A total of 5909 Hyalomma adult ticks collected from cattle (3362/5909) and shelters (2447/5909) were dissected and salivary glands were stained with Methylgreen/Pyronin method. Thousand one hundred and fifty (46.9%) of 2447 H.a. anatolicum collected from shelters and 412 (19.1%) of 2147 H.a. anatolicum collected from cattle were positive for Theileria infection. Twenty (2.4%) of 820 H.a. excavatum and 23 (4.6%) of 495 H. detritum collected from cattle were positive. The mean number of infected acini per infected male and female ticks collected from cattle were 11.3 and 22.4 in H.a. anatolicum, 4 and 6.8 in H.a. excavatum, 17.9 and 18.3 in H. detritum, respectively. In H.a. anatolicum collected from shelters, the above rates were 11.8 and 17.6 in male and female ticks, respectively. The prevalence and intensity of Theileria infection was greater in female ticks than in males.  相似文献   

18.
The aim of this study was to determine the population of ticks in infected cattle and to identify the tick vectors of bovine theileriosis in an endemic area of Iran from 1998 to 1999. A total of 120 suspected cattle suffering from theileriosis were clinically examined and investigated for the presence of Theileria annulata in blood smears and the presence of any tick species on the body of cattle. In this study, 680 ticks were collected from 107 cattle infected with T. annulata. The prevalence of ticks infesting cattle was 92.35% Hyalomma anatolicum excavatum, 5.14% H. marginatum marginatum, 1.17% H. asiaticum asiaticum and 1.32% Rhipicephalus sanguineus. The examination of 510 tick salivary glands revealed that 51% of H. a. excavatum and 1.3% of H. a. asiaticum were infected with sporozoites of T. annulata.  相似文献   

19.
A sporozoite stabilate (St. 199) of Theileria parva was obtained by feeding nymphal Rhipicephalus appendiculatus on an African buffalo (Syncerus caffer) and was used to immunize cattle by the infection and treatment method. Nymphal ticks were applied to one of the steers 90 days later and it was shown that the resultant adult tick had become infected. Using tick/cattle passage, two passage lines of T. parva were established. By the fifth tick/cattle passage, the parasite stocks had changed their behaviour to that of T. parva derived from cattle as the parasite produced relatively high schizont parasitosis and piroplasm parasitaemia in cattle, and had become highly infective to ticks. At various passage levels the parasite populations were characterized by behaviour and by monoclonal antibodies against T. parva schizonts using infected cell culture isolates from cattle during acute infections. The monoclonal antibody profile showed little evidence of antigen change of the parasite during passage through cattle, which was confirmed in a two-way cross-immunity experiment using sporozoite stabilate derived from ticks obtained from the buffalo and fourth passage in cattle. The implication of these results, particularly in relationship to immunization of cattle against T. parva derived from buffalo, is discussed.  相似文献   

20.
A survey was carried in North Khorasan Province, Iran in 2010–2011, designed to identify Theileria spp. infections of both sheep and ticks. The tick species were also examined. Ninety sheep from different flocks were clinically examined, and blood samples and ixodid ticks were collected. Light microscopy of blood smears revealed Theileria spp. infection in 37 (41.1 %), while 74 (82.2 %) of blood samples were positive using semi-nested PCR. Theileria ovis, Theileria lestoquardi, and mixed infection were detected in 63/90 (70 %), 5/90 (5.5 %), and 6/90 (6.6 %) of samples, respectively. Of the 434 ticks that were collected, the most prevalent species was Rhipicephalus turanicus (69.3 %) followed by Hyalomma marginatum turanicum (18.4 %), Dermacentor marginatus (6.4 %), and Rhipicephalus bursa (5.7 %). The ticks were separated into 42 tick pools, and the salivary glands were dissected out in 0.85 % (w/v) saline under a stereomicroscope and examined using semi-nested PCR. Three pools of H. marginatum turanicum salivary glands were infected with T. ovis and T. lestoquardi, and one pool of R. turanicus was infected with T. ovis. Based on these results, it is concluded that the prevalence of T. ovis is higher than T. lestoquardi and that H. marginatum turanicum and R. turanicus are likely vectors of T. lestoquardi and T. ovis in this area.  相似文献   

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