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1.
This study was carried out to compare different diagnostic techniques to reveal the presence of piroplasms in asymptomatic cattle kept at pasture. Nineteen blood samples were collected from animals of two different areas of Emilia Romagna Region of Italy and processed for microscopic observation, PCR, serological test (IFAT) for Babesia bovis and Babesia bigemina antibodies and in vitro cultivation. The cultures were performed on both bovine and ovine erythrocytes. Seventeen blood smears (89%) were positive for piroplasms, while PCR was positive on 18 samples (95%). DNA sequencing of 18S rRNA identified the piroplasms as Theileria spp. In vitro cultures were successful for 6 samples (32%) cultured on bovine blood and subsequent identified these as Babesia major by PCR. On IFAT analyses of 16 samples, 36.8% resulted positive for B. bovis and 31.6% positive for B. bigemina. These results show, in the same animals, the co-infection with Babesia spp. and Theileria spp.; the detection of B. major was possible only using the in vitro cultures.  相似文献   

2.
Reverse line blot (RLB) is a hybridization assay that can be used to detect various blood parasites and differentiate between them. Results, using the RLB, showed that Babesia felis and Babesia leo occurred as single or mixed infections in various felid species, but most frequently in domestic cats and lions, respectively. Prevalence of infection in free-ranging cheetahs in Namibia was low (7, 5%), whereas 50% of free-ranging lions in South Africa and Swaziland were infected. A large number (52, 9%) of samples tested positive only for Babesia, neither B. felis nor B. leo. This could be an indication of at least one further, as yet undescribed, Babesia species in felids.  相似文献   

3.
Small piroplasms as a cause of canine babesiosis in southern California were first documented in 1990. Initially these piroplasms were considered to be Babesia gibsoni, the only small Babesia parasite known to infect dogs at that time. In the following decade, the use of molecular analysis made it clear that small canine Babesia in fact are comprised of at least three distinct species, and the isolates from dogs in southern California were not B. gibsoni. Molecular, antigenic, and morphological characteristics of the southern California species of canine piroplasm supported naming it as a distinct species, Babesia conradae. The renaming of this species prompted this literature review of small canine piroplasms in California in order to clarify clinical, diagnostic, epidemiological, and molecular characteristics of B. conradae in comparison to other small canine piroplasms. Clinical symptoms of B. conradae are similar to those of B. gibsoni; however, B. conradae infections may be more pathogenic, resulting in higher parasitaemia and more pronounced anaemia when compared with B. gibsoni-infected dogs. The immunofluorescent antibody test is the most commonly used test to diagnose B. conradae. It is important to specify which small Babesia species to test for since there is little serological cross reactivity between the small canine Babesia antigens or cross-detection in the newer molecular tests. Molecular characterization of B. conradae, based principally on the 18S small subunit rRNA gene, and recently the second internal transcribed spacer region, demonstrate that B. conradae is most closely related to piroplasms recovered from humans and animals in the western United States.  相似文献   

4.
A 5-month-old intact male Boerboel dog, imported from South Africa 1 week previously, was presented to a Texas veterinarian for lethargy, anorexia, and labored breathing. The dog was febrile, anemic, leukopenic, thrombocytopenic, and slightly azotemic. Results of the IDEXX SNAP-4Dx enzyme immunoassay were negative for Dirofilaria immitis antigen and antibodies against Ehrlichia canis, Borrelia burgdorferi, and Anaplasma phagocytophilum. An EDTA blood sample analyzed at Oklahoma State University Center for Veterinary Health Sciences revealed nonregenerative anemia, neutropenia, and large protozoal piroplasms in 0.7% of the RBCs. Piroplasms were 2-5μm long and varied in shape from round to oval to piriform; extracellular merozoites were also observed. Nested PCR was performed on DNA extracted from blood using primers that amplify the 18s rRNA gene from all known Babesia species, and the product was sequenced. Basic Local Alignment Search Tool analysis of the 437 base sequence revealed 99-100% similarity to Babesia canis rossi, 92-93% similarity to Babesia canis canis, and 92% similarity to Babesia canis vogeli. The dog responded well to treatment with imidocarb. PCR analysis of a second blood sample 2 weeks later was negative for Babesia spp. DNA. This case represents the first diagnosis of B. canis rossi infection in the United States.  相似文献   

5.
Equine piroplasmosis due to Theileria equi and Babesia caballi is endemic in Trinidad. A case of equine piroplasmosis due to T. equi was diagnosed in a thoroughbred foal at 10h post-partum. A high parasitaemia (63%) of piroplasms was observed in a Wright-Giemsa(?) stained thin blood smear from the foal. In addition, the 18S rRNA gene for Babesia/Theileria was amplified from DNA extracted from the blood of the foal and the mare. Amplified products were subjected to a reverse line blot hybridization assay (RLB), which confirmed the presence of T. equi DNA in the foal. The mare was negative by RLB but was positive for T. equi using a nested PCR and sequence analysis. In areas where equine piroplasmosis is endemic, severe jaundice in a post-partum foal may be easily misdiagnosed as neonatal isoerythrolysis. Foals with post-partum jaundice should be screened for equine piroplasmosis, which may be confirmed using molecular methods if available.  相似文献   

6.
Canine babesiosis represents an important veterinary medical problem. This study describes the molecular characterization of babesial parasites detected in eight clinically suspected dogs from northern Portugal, affected by lethargy, muscle tremors, weight loss, pale mucous membranes, hyperthermia or red-coloured urine. Microscopic examination of peripheral blood smears showed large intraerythrocytic piroplasms morphologically compatible with Babesia canis in all eight animals. DNA was extracted from blood on filter paper, and a Babesia spp. infection confirmed by polymerase chain reaction (PCR) amplification of a 408bp fragment of the 18S rRNA gene. Analysis of PCR-derived sequences revealed that seven dogs were infected with B. canis canis and one with B. canis vogeli. This is the first molecular identification report of both the species B. canis and the subspecies B. canis canis and B. canis vogeli in dogs from Portugal.  相似文献   

7.
Equine piroplasmosis caused by Babesia caballi and Theileria equi is widespread in Asia. The presence of these haemozoans in Mongolia was previously confirmed in domestic as well as in reintroduced Przewalski horses in which they cause significant pathology. The data on occurrence of piroplasms from Bactrian camels in Asia is lacking. A total of 192 horses, 70 Bactrian camels, and additional 16 shepherd dogs from the Hentiy province were included in our study. No clinical signs typical for piroplasmid infection were observed during the field survey. Microscopic examination revealed the presence of T. equi in blood smears from 67% of examined horses, with camels and dogs being negative. A two step PCR approach was used to detect piroplasms in peripheral blood. In the first "catch all" PCR reaction, amplification of the 496 bp-long fragment of the SSU rRNA gene enabled the detection of Babesia and Theileria spp. Second round multiplex PCR reaction used for species discrimination allowed the amplification of T. equi- and B. caballi-specific 340 bp and 650 bp-long regions of the SSU rRNA, respectively. This assay detected T. equi in 92.7% of horses, while the infections with B. caballi and dual infections were rare. In both PCR setups, camels and dogs were negative indicating that in the studied region, these hosts do not share piroplasms with horses.  相似文献   

8.
This study documents the seroprevalence of feline immunodeficiency virus (FIV) and puma lentivirus (PLV) in free-ranging and captive Florida panthers (Puma concolor coryi) (n = 51) and translocated Texas cougars (P. concolor stanleyana) (n = 10) from 1985 to 1998. The sera were tested for anti-FIV antibodies by enzyme-linked immunosorbent assay (ELISA) and Western blot tests. The ELISAs were read kinetically (KELA) and the sera were retrospectively examined by PLV peptide ELISA. Eleven panthers and one cougar were positive by KELA; 4 panthers and 4 cougars were equivocal; 35 panthers and 5 cougars were negative; and 1 panther had no data. Seven of the 11 KELA-positive panthers were also positive by Western blot tests and all but one were positive by PLV peptide ELISA. Ten KELA-negative and Western blot-negative cats, were positive by PLV peptide ELISA. KELA results varied within cats from one sample period to the next, but PLV peptide ELISA results were consistent. Territorial sympatry and mating behaviour, noted from radiotelemetry location data on the cats, may have contributed to viral transmission between seropositive animals. These findings suggest that Florida panthers and the introduced Texas cougars have been exposed to FIV and/or PLV.  相似文献   

9.
The present paper is the continuation of our previous studies dealing with the genetic characterization of piroplasmid species found in southern Europe. We report in this work new data concerning sequences of the 18s rRNA gene in Spanish piroplasms not studied (or not totally sequenced) in our former surveys. Molecular data analysis indicated that Spanish Cytauxzoon felis (cat isolate) has 98% identity with Cytauxzoon sp. from Mongolia and 95% identity compared to African C. felis. There are at least two main genetic variants of Babesia caballi in Spain: The first variety (isolate Spain 1) shows a relatively low homology with the African genotype (97% identity). The second variety (represented by two isolates, Spain 2 and Spain 3, differing by a single base) shows high genetic similarity with the African genotype (99.7-100% identity). There are also two genetic variants of Babesia equi (isolates Spain 1 and Spain 2, differing by four bases) in Spain, sharing 99% identity with the African genotype. At least one of them (Spain 1) can infect dogs. All of the phylogenetic analysis procedures employed indicated that Spanish isolates of C. felis, B. caballi (Spain 1) and B. equi (Spain 1 and Spain 2) are genetically different from their African relatives, all those dichotomies showing very high bootstrap support. Nonetheless, the lack of information on their morphology and the fact that the sequences were obtained in a single isolate preclude any conclusion about their definitive taxonomic status.  相似文献   

10.
Freshly collected blood and/or spleen homogenate from an experimentally infected Florida bobcat (Lynx rufus floridanus), which had died of feline cytauxzoonosis, was inoculated into domestic cats. All inoculated cats had clinical signs of feline cytauxzoonosis and died within 2 weeks after they were inoculated. Similar material collected from an eastern bobcat (Lynx rufus rufus) carrying an experimentally infected Cytauxzoon felis parasitemia was inoculated into domestic cats. All inoculated cats developed a parasitemia, but none developed clinical signs of disease and none died of the disease. Cats subinoculated with parasitemic cat blood also developed parasitemias and they too did not develop clinical signs of infection nor died. After carrying the blood phase of Cytauxzoon felis for various periods, the domestic cats were then challenge exposed with proven lethal Cytauxzoon inoculum of domestic cat origin. All cats died of cytauxzoonosis.  相似文献   

11.
Specific oligonucleotide probes were designed to develop a new and highly sensitive reverse line blot assay to detect and identify simultaneously different Theileria and Babesia species in horses. The amplified hypervariable V4 region of the 18S rRNA gene was hybridised against different generic and species-specific probes. The survey was conducted over 243 samples of equine blood divided into three different groups: group 1, 24 horses presented as possible clinical piroplasmosis; group 2, 181 clinically healthy free-ranging horses exposed to ticks; group 3, 38 riding horses with unrelated pathologies and low or no contact with ticks. The study demonstrated a high piroplasm prevalence in the first two groups of animals. Two Theileria genotypes sharing 96.8% similarity between their 18S rRNA gene sequences and two Babesia genotypes sharing 97.4% similarity, were identified. The biologic meaning of such genotypes is discussed in terms of their phylogenetic relationships and potential pathogenicity.  相似文献   

12.
Florida manatees (Trichechus manatus latirostris) are endangered aquatic mammals living in coastal and riverine waterways of Florida and adjacent states. Serum or plasma biochemical analyses are important tools in evaluating the health of free-ranging and captive manatees. The purpose of this study was to measure diagnostically important analytes in the plasma of healthy manatees and to determine whether there was significant variation with respect to location (free-ranging versus captive), age class (small calves, large calves, subadults, adults), and gender. No significant differences in plasma sodium, potassium, bilirubin, glucose, alanine aminotransferase, or creatine kinase were found among these classes of animals. Compared to free-ranging manatees, captive animals had significantly lower mean concentrations of plasma chloride, phosphate, magnesium, triglycerides, anion gap, and lactate. Captive manatees had significantly higher mean values of total CO2, calcium, urea, creatinine, alkaline phosphatase, gamma-glutamyltransferase, total protein, albumin, and albumin/globulin ratio than did free-ranging animals. Differences in the environments of these two groups, including diet, temperature, salinity, and stress, might account for some of these results. The higher plasma lactate and anion gap concentrations and lower total CO2 concentrations of free-ranging manatees were probably due to greater exertion during capture, but the lack of elevated plasma creatine kinase activity relative to captive animals indicates that there was no serious muscle injury associated with capture. Plasma phosphate decreased and total globulins increased with age. Plasma cholesterol and triglyceride concentrations were highest in small calves. Plasma aspartate aminotransferase was higher in large calves than in adults and subadults, and the albumin/ globulin ratio was higher in subadults than in adults. Plasma total CO2 was higher and chloride was slightly lower in females than in males.  相似文献   

13.
Some observations are recorded on blood parasites of sable antelopes. Blood smears of 124 of these antelopes from South Africa and Zimbabwe were examined and 7 were found to be positive for a Babesia sp., identified as Babesia irvinesmithi Martinaglia 1936. A total of 70 of the smears were positive for theilerial piroplasms, while 1 smear had macroschizonts (with cytomeres) and microschizonts of a Theileria (= Cytauxzoon) sp. One blood smear was positive for an Anaplasma sp. Attempts to isolate the Babesia sp. by subinoculating blood from sable to splenectomized and intact sable and splenectomized cattle were unsuccessful. Attempts to infect sable with Babesia bovis and Babesia bigemina were likewise unsuccessful. Theilerial piroplasms reached high levels in a splenectomized sable but could not be transmitted with blood to cattle. The Anaplasma sp. was found to be infective for sheep but not for cattle.  相似文献   

14.
Cytauxzoon felis, a protozoan parasite of wild and domestic felids, is the causative agent of cytauxzoonosis in domestic and some exotic felids in the United States. The bobcat (Lynx rufus) is the natural reservoir for this parasite, but other felids such as Florida panthers (Puma concolor coryii) and domestic cats may maintain long-term parasitemias and serve as reservoirs. Experimentally, two tick species, Dermacentor variabilis and Amblyomma americanum, have demonstrated the ability to transmit C. felis. These two tick species have overlapping distributions throughout much of the southeastern United States. The objective of the current study was to determine the distribution and prevalence of C. felis in free-ranging bobcat populations from 13 states including California, Colorado, Florida, Georgia, Kansas, Kentucky, Missouri, North Carolina, North Dakota, Ohio, Oklahoma, South Carolina, and West Virginia. These states were selected because of differential vector presence; D. variabilis is present in each of these states except for the region of Colorado sampled and A. americanum is currently known to be present only in a subset of these states. Blood or spleen samples from 696 bobcats were tested for C. felis infection by a polymerase chain reaction (PCR) assay which targeted the first ribosomal internal transcribed spacer region (ITS-1). Significantly higher prevalences of C. felis were detected from Missouri (79%, n=39), North Carolina (63%, n=8), Oklahoma (60%, n=20), South Carolina (57%, n=7), Kentucky (55%, n=74), Florida (44%, n=45), and Kansas (27%, n=41) compared with Georgia (9%, n=159), North Dakota (2.4%, n=124), Ohio (0%, n=19), West Virginia (0%, n=37), California (0%, n=26), and Colorado (0%, n=67). In addition to bobcats, seven cougars (Puma concolor) from Georgia, Louisiana, and North Dakota and one serval (Leptailurus serval) from Louisiana were tested for C. felis. Only one cougar from Louisiana was PCR positive, which represents the first report of an infected cougar outside of the Florida panther population. These data also indicate that C. felis is present in North Dakota where infection has not been reported in domestic cats. Based on a nonparametric analysis, prevalence rates were significantly higher in states where there are established populations of A. americanum, which supports recent data on the experimental transmission of C. felis by A. americanum and the fact that domestic cat clinical cases are temporally associated with A. americanum activity. Collectively, these data confirm that bobcats are a common reservoir for C. felis and that A. americanum is likely an epidemiologically important vector.  相似文献   

15.
Babesiosis in the Greyhound   总被引：1，自引：0，他引：1  
Babesiosis was diagnosed in five 11- to 18-day old Greyhound pups. In 3 pups, Babesia canis organisms were identified by examination of a Wright's-Giemsa-stained smear of blood. In 2 pups, the diagnosis was established by examination of a splenic impression smear obtained at necropsy. Findings in the 3 clinical cases included depression, weakness, anorexia, pallor, anemia, and thrombocytopenia. Subcutaneous administration of diminazene aceturate resulted in rapid clinical recovery in these cases. In the 2 pups that were necropsied, variable numbers of erythrocytes containing Babesia organisms were observed in the microvasculature of tissues. Subinoculation of blood into an intact dog and a splenectomized dog resulted in parasitemia and B canis serum titers, as determined by indirect fluorescent antibody testing. A site visit to the kennel from which the pups had originated led to identification of numerous Rhipicephalus sanguineus in small buildings and pens. Of 107 dogs from this kennel that were tested, 63 had an indirect fluorescent antibody titer for B canis. A limited serologic survey of Greyhound kennels in West Virginia, Oklahoma, Texas, Mississippi, and Florida identified a large number of dogs with indirect fluorescent antibody titers for B canis.  相似文献   

16.
Liu Q  Zhou YQ  Zhou DN  Liu EY  Du K  Chen SG  Yao BA  Zhao JL 《Veterinary parasitology》2007,143(3-4):260-266
Babesiosis has recently been recognized as an emerging infectious disease of buffalo in China. In order to investigate the epidemiology and enzootic potential of this parasite in Hubei province, we sought to develop a semi-nested PCR to detect Babesia orientalis in buffalo and the potential tick vector-Rhipicephalus haemaphysaloides by amplifying a specific 257bp fragment of B. orientalis 18S rRNA gene. The practical limit of detection showed that it had high sensitivity and an approximate parasitemia of 0.00000012% was detected by the PCR system. The blood samples of 121 asymptomatic buffaloes collected from four babesia endemic counties and that of 71 asymptomatic buffaloes collected from three babesia free counties in Hubei province of China were examined for the presence of B. orientalis using both Wright-Giemsa stained blood smear and semi-nested PCR. Microscopic examination revealed that 5/121 animals were positive, whereas 24/121 animals were positive by the semi-nested PCR assay. Of 378 ticks (R. haemaphysaloides) collected from buffaloes and examined by the semi-nested PCR, 35 were positive. The results showed that the semi-nested PCR was a useful method to investigate the epidemiology of buffalo babesiosis (B. orientalis), which is widely distributed in Hubei province, China.  相似文献   

17.
Haemobartonella felis is an epierythrocytic bacterium suspected to be the causative agent of feline infectious anemia. Previous studies with a polymerase chain reaction assay have identified a mycoplasmal 16S rRNA gene sequence that coincides with clinical disease and the presence of organisms in the blood. Tissues from a cat experimentally infected with H. felis were used for in situ hybridization studies to physically link this 16S rRNA gene to the organisms on the red cells. A biotin-labeled probe was used in conjunction with tyramide signal amplification to visualize the hybridization signal. This study clearly demonstrates a specific hybridization signal on the red cells in the tissues of the H. felis-infected cat. This in situ hybridization study is the final step in fulfilling the molecular guidelines for disease causation and proves that H. felis, a mycoplasmal organism, is the causative agent of feline infectious anemia.  相似文献   

18.
Ovine babesiosis, caused by Babesia ovis, is of major economic importance in Turkey. The changes in the blood profile of infected animals are informative about the course of infection. The aim of the present study was to evaluate the hematological and biochemical changes in the pre- and post-treatment periods of the natural B. ovis infections. The presence of the parasites was confirmed by microscopy and polymerase chain reaction (PCR) analysis. On the basis of the clinical and laboratory findings, the infections were categorized into different groups according to the degree of anemia and the level of parasitemia. All infected sheep were treated with imidocarb dipropionate (IMDP). The blood pictures in the pre- and post-treatment periods were compared.Pancytopenia occurred in animals with severe anemia and very high parasitemia, and bicytopenia in the other groups. The platelet count (PLT), plateletcrit (PCT) and mean platelet volume (MPV) returned to the normal ranges after treatment, except those in the group with severe anemia. In the biochemical profile, B. ovis infection caused an increase in blood urea nitrogen and total bilirubin, and these parameters returned to normal levels after treatment.The indirect fluorescein antibody test (IFAT) results showed that 38.1% of the cases raised specific antibodies during the period of infection, with titers ranging from 1/160 to 1/640. All of 45 animals re-examined after treatment were seropositive, with high titers that rose up to 1/5120.  相似文献   

19.
OBJECTIVE: To characterize clinical and hematologic responses in dogs following experimental inoculation with Babesia gibsoni-like isolates from infected dogs in Oklahoma. DESIGN: Prospective study. ANIMALS: 6 mixed-breed dogs. PROCEDURE: 2 dogs were inoculated with organisms from a naturally infected dog, and 3 were inoculated with organisms from a second naturally infected dog (1 of these 3 dogs was splenectomized 1 week prior to inoculation). One dog was not inoculated. Complete blood counts were performed weekly. RESULTS: In the 5 dogs inoculated with organisms, parasites were initially detected 1 to 5 weeks after inoculation, and severity of parasitemia peaked with 1.9 to 6.0% of RBC infected by 4 to 6 weeks after inoculation. Parasitemia was easily detectable (> 0.1% of RBC infected) for 3 to 4 weeks. Clinical abnormalities included lethargy, fever, and pale mucous membranes but were mild to nearly inapparent in 2 dogs. All dogs developed regenerative anemia and marked thrombocytopenia. Thrombocytopenia developed before and lasted longer than the parasitemia. Profound but transient neutropenia was detected in some dogs. The splenectomized dog developed more severe parasitemia and anemia and more pronounced clinical abnormalities. Three dogs with intact spleens recovered without treatment. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that 2 or more genotypically distinct, but morphologically identical, small Babesia parasites can infect dogs in the United States. Compared with infection with small Babesia parasites from California, infection with these isolates resulted in less severe parasitemia and clinical abnormalities. Parasitemia was transient, indicating that identification of organisms in blood smears may be difficult in some dogs.  相似文献   

20.
Canine babesiosis.   总被引：6，自引：0，他引：6  
Canine babesiosis is a tickborne, protozoal, hemoparasitic disease that can cause varying degrees of hemolytic anemia, splenomegaly, thrombocytopenia, and fever. Babesia organisms frequently are classified as large or small. Large Babesia infections are attributed to one of three subspecies of Babesia canis. All small Babesia infections previously were attributed to B gibsoni, but molecular analysis and DNA sequencing have revealed that there are at least three small piroplasms infecting dogs. Correctly identifying the infectious agent is important for treatment planning and prognosis.  相似文献   

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