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1.
The infectivity rate of Babesia equi in the salivary glands of Hyalomma anatolicum anatolicum was assessed. The hungry nymphs were fed on a donkey experimentally infected with B. equi. The engorged dropped-off nymphs were collected at different levels of parasitaemia and kept in BOD incubator. After ecdysis, the hungry adults were prefed on rabbits for different time intervals, thereafter the salivary glands were dissected out and acini were examined after methyl green pyronin (MGP) staining. A total of 134 male and 139 female ticks were dissected out. Average infected acini per tick were found to be significantly higher (p<0.05) in male as compared to the female ticks. Further, maximum infected acini in both male and female ticks were found at 24h of prefeeding on rabbits and overall infected acini per tick increased with rise in parasitaemia. The release of infected ticks on susceptible donkeys resulted in development of clinical babesiosis.  相似文献   

2.
Yin H  Luo J  Guan G  Lu B  Ma M  Zhang Q  Lu W  Lu C  Ahmed J 《Veterinary parasitology》2002,108(1):21-30
Experiments on the transmission of an unidentified Theileria sp. infective for small ruminants by Haemaphysalis qinghaiensis and Hyalomma anatolicum anatolicum were carried out. Three Theileria-free batches of adult, larvae, and nymphs of laboratory reared H. qinghaiensis and Hy. a. anatolicum ticks were infected by feeding them on sheep infected with Theileria sp. The Theileria sp. was originally isolated from adult ticks of H. qinghaiensis, by inoculation of blood stabilates or tick transmission. H. qinghaiensis has been shown to be capable of transmitting the Theileria sp. infective for small ruminants transstadially to sheep and goats. The nymphs developed from the larvae engorged on the sheep infected with the parasite transmitted the pathogen to splenectomized sheep with prepatent periods of 30, 31 days, respectively; but the subsequent adult ticks of H. qinghaiensis derived from the nymphs did not transmit the pathogen to sheep. However, adults developed from the nymphs engorged on the sheep infected with the parasite transmitted the pathogen to sheep with prepatent periods of 24-27 days. The larvae, nymphs and adult ticks derived from female H. qinghaiensis ticks engorged on infected sheep were not able to transmit the parasite transovarially. The same experiments were done with Hy. a. anatolicum, but examination for presence of piroplasma of Theileria sp. from all animals were negative, demonstrating that Hy. a. anatolicum could not transmit the organism to sheep or goats.  相似文献   

3.
A crossbred calf (3 months old) obtained from a farm where regular control of ticks was practised and found to be free of blood parasites was inoculated with 20 ml pooled blood collected from four field cattle which had very low Trypanosoma theileri parasitaemias (one parasite per 70 microl blood as determined by the haematocrit centrifugation technique). Trypanosoma theileri was present in the blood 6 days after injection and a peak parasitaemia of 42 parasites per 70 microl blood was recorded by day 12. Hyalomma anatolicum anatolicum nymphs were applied on the ears of the calf on day 8 and they dropped engorged by days 13 and 14. The resulting adult ticks were examined for the presence of T. theileri by severing a leg and making a smear of the clear haemolymph which exuded from the wound. The smear was fixed in methanol and stained with Giemsa stain. The infection rate with T. theileri in the ticks was 43.3% (26 out of 60). The intensity of infection was very high and various developmental stages of the flagellates were observed (epimastigotes, sphaeromastigotes, trypomastigotes and other intermediate stages). The haemolymph from 12 ticks was also collected in tissue culture medium and the trypanosomes survived for 25 weeks before eventually dying. The results demonstrated unequivocally the high vectorial capacity of the tick H. a. anatolicum for T. theileri.  相似文献   

4.
Sixty three cross-bred (Bos taurus X Bos indicus) 4-5-day-old calves were divided into 16 groups (A-P). Each calf in Groups A and B was given ground-up-tick supernate prepared from Theileria annulata-infected or non-infected Hyalomma anatolicum anatolicum (GUTS) equivalent to 5 ticks (50 infected acini). Groups D and E received infected GUTS equivalent to 2 ticks (20 infected acini) and Groups G and H were given infected GUTS equivalent to 1 tick (10 infected acini). Each calf in Groups J, K and L received infected GUTS equivalent to 5 infected acini (0.035 tick), and Group O was inoculated with non-infected GUTS equivalent to 5 ticks. Each calf in Groups A, D, G, J, K and O was also given a single intramuscular injection of long acting oxytetracycline, 20 mg kg-1 body weight just after inoculation of GUTS. Severe reactions resulted in the death of five of eight, three of eight, five of six, one of five and one of five calves in Groups A, D, G, J and K respectively and all of the calves in Groups B, E, H, and L. The surviving calves of Groups A, D, G, J, K and O were challenged on Day 45 post-immunization along with freshly introduced susceptible control calves of Groups C, F, I, M, N and P. All the calves of Groups A, G, J and K withstood the challenge dose; in Group D four of five and in Groups C, F, I, M, N, O, and P all the calves died of theileriosis. It is concluded that though the infection and treatment method of immunization may be used for neonatal bovines, the dose of immunogen should be based on actual counts of infected salivary acini of ticks instead of the number of ticks.  相似文献   

5.
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   

6.
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   

7.
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   

8.
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   

9.
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   

10.
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   

11.
Sun M  Ren Q  Guan G  Liu Z  Ma M  Gou H  Chen Z  Li Y  Liu A  Niu Q  Yang J  Yin H  Luo J 《Veterinary parasitology》2011,180(3-4):389-393
The tick is a common ectoparasite of livestock and humans, and is responsible for the transmission of pathogens among hosts. Direct and indirect impacts of ticks include limiting the sustainable development of the animal husbandry industry and detrimental effects on human health. Despite these negative effects, the main method of controlling ticks remains the application of chemical acaricides, which can lead to ambient pollution and the development of tick resistance to them. The biocontrol of ticks is one of the alternative control methods that has received recent research attention. The present study used Tenebrio moliter bait methods to collect 13 species of entomopathogenic fungi from different areas in China that were then tested to observe their effects on engorged female Hyalomma anatolicum anatolicum ticks. The results showed that more than half of the isolates had some pathogenic effects on the ticks; in particular, two Beauveria bassiana strains (B.bAT01, B.bAT17) and one Metarhizium anisopliae strain (M.aAT26) were highly virulent, causing up to 90% mortality. In addition, H. anatolicum anatolicum females were treated with B. bassiana B.bAT17 using different concentrations of the fungus. Results revealed that B. bassiana B.bAT17 is highly pathogenic against engorged H. anatolicum anatolicum females. This is the first report of the pathogenic effect of entomopathogenic fungi on engorged H. anatolicum anatolicum females. However, studies of the efficiency of this fungus against ticks in the field are required before it can be used for tick management in practice.  相似文献   

12.
During feeding of ticks of the species Hyalomma anatolicum anatolicum, most of the proteins in salivary gland extracts (SGEs) remained unchanged from the unfed to the fully fed state (from day 1 to day 7 of the experiment), as revealed by SDS-PAGE. However, a 45-kDa protein band disappeared and 26-, 32- and 33-kDa bands appeared when feeding commenced. Some of the protein bands changed their intensity. When probed with anti-H. anatolicum anatolicum hyperimmune sera, transblotted SGE proteins of unfed H. anatolicum anatolicum and Hyalomma dromedarii revealed two common bands of 105 and 80 kDa. A 36-kDa protein band present in H. anatolicum anatolicum SGE could not be detected in H. dromedarii. None of these proteins were detected in partly fed Boophilus microplus when probed with anti-H. anatolicum anatolicum hyperimmune serum. This H. anatolicum anatolicum specific 36-kDa protein was strongly recognized throughout feeding, and thus may be an immunogen of importance for the development of an H. anatolicum anatolicum specific serodiagnostic assay.  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.
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   

15.
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   

16.
Studies were undertaken to determine the effect of repeated pure infestations with Boophilus microplus on susceptibility to subsequent pure infestations with Hyalomma anatolicum anatolicum, and the effects of pure infestations with both species of tick on susceptibility to a series of mixed infestations. Crossbred (Bos indicus X Bos taurus) calves were infested with Boophilus microplus (17 times), H. a. anatolicum (four times), followed by five mixed infestations of B. microplus and H. a. anatolicum. The decline in B. microplus engorgement from a mean yield of 274.4 +/- 60.3 ticks per host after the first exposure, to a mean yield of 9 +/- 4.6 per animal after the seventeenth exposure, was observed in animals exposed to only B. microplus. This might be due to acquired resistance. However, these animals were found to be as susceptible to H. a. anatolicum as animals which had never been exposed to ticks of either species. A decline in the yield of H. a. anatolicum from a mean yield of 92.1 +/- 10.7 after the first exposure to 54.7 +/- 11.3 after the fourth exposure, indicated that the cattle could also acquire resistance to repeated pure infestations with this species. After repeated pure infestations with both tick species, cattle reacted to five mixed infestations showing a high degree of resistance to B. microplus and low resistance to H. a. anatolicum (mean yield for B. microplus was only 10 +/- 8.1 ticks per host after the first mixed exposure and declined to 1.3 +/- 1.7 after the fifth, whereas the mean yield for H. a. anatolicum was 71.4 +/- 11.3 ticks per host following the first exposure and declined to 37.3 +/- 7.8 after the fifth). Host responses elicited to one species do not provide cross-resistance to the second species used in this study.  相似文献   

17.
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   

18.
本研究旨在建立小亚璃眼蜱、亚洲璃眼蜱和残缘璃眼蜱的分子生物学鉴定方法,并探讨它们的系统发生关系。在新疆、内蒙古从动物体表采集寄生蜱,形态学鉴定后,PCR扩增测序获得3种璃眼蜱的16S rRNA及线粒体色素氧化酶亚基Ⅰ基因(cytochrome oxidaseⅠ,COⅠ)序列后进行同源性分析。用Mega 5.0和Mrbayes 3.2软件分别构建系统进化树,亚洲璃眼蜱、小亚璃眼蜱样本16S rRNA序列与GenBank中已知相应蜱虫16S rRNA序列聚类,而残缘璃眼蜱COⅠ序列与GenBank中已知残缘璃眼蜱COⅠ序列聚类,与形态学鉴定结果一致。在传统形态学分类的基础上,结合分子生物学鉴定方法能简易、准确鉴定小亚璃眼蜱、亚洲璃眼蜱和残缘璃眼蜱。  相似文献   

19.
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   

20.
Eighteen seven to 21-day-old crossbred (Bos taurus cross Bos indicus) calves were allocated to four groups (A to D). Groups A and B each consisted of six calves and groups C and D three calves each. Each calf in groups A, B and C was inoculated with ground-up tick supernate (GUTS) equivalent to two infected acini prepared from Theileria annulata-infected Hyalomma anatolicum anatolicum. Each calf in group A was also given a single intramuscular injection of buparvaquone, 2.5 mg kg-1 bodyweight simultaneously with GUTS, whereas each calf in group B was given a single intramuscular injection of long-acting oxytetracycline, 20 mg kg-1 bodyweight following inoculation of GUTS. In calves of group A clinicopathological reactions were negligible, whereas in calves of group B mild to severe reactions were observed resulting in the death of three of the six calves. All the calves of group C (infected, untreated controls) died of acute theileriosis. All the surviving calves of groups A and B withstood a lethal homologous challenge given on day 30 after immunisation, indicating no difference in the immune status of the surviving calves of the two groups. Group D, challenge control, all calves died of theileriosis within 18 days of challenge.  相似文献   

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