Evolution of clinical, haematological and biochemical findings in young dogs naturally infected by vector-borne pathogens

Longitudinal studies evaluating the evolution of clinical, haematological, biochemical findings in young dogs exposed for the first time to multiple vector-borne pathogens have not been reported. With the objective of assessing the evolution of clinical, haematological and biochemical findings, these parameters were serially monitored in naturally infected dogs throughout a 1-year follow-up period. Young dogs, infected by vector-borne pathogens based on cytology or polymerase chain reaction, were examined clinically and blood samples were obtained at seven different follow-up time points. Dogs were randomized to group A (17 dogs treated with a spot-on formulation of imidacloprid 10% and permethrin 50%) or to group B (17 dogs untreated). In addition, 10 4-month-old beagles were enrolled in each group and used as sentinel dogs. At baseline, Anaplasma platys was the most frequently detected pathogen, followed by Babesia vogeli, Bartonella spp., Ehrlichia canis and Hepatozoon canis. Co-infections with A. platys and B. vogeli, followed by E. canis and B. vogeli, A. platys and H. canis and A. platys and Bartonella spp. were also diagnosed. In dogs from group B, abnormal clinical signs were recorded at different time points throughout the study. No abnormal clinical signs were recorded in group A dogs. Thrombocytopenia was the most frequent haematological alteration recorded in A. platys-infected dogs, B. vogeli-infected dogs and in dogs co-infected with A. platys and B. vogeli or A. platys and Bartonella spp. Lymphocytosis was frequently detected among dogs infected with B. vogeli or co-infected with A. platys and B. vogeli. Beagles were often infected with a single pathogen rather than with multiple canine vector-borne pathogens. There was a significant association (p<0.01) between tick infestation and A. platys or B. vogeli, as single infections, and A. platys and B. vogeli or A. platys and Bartonella spp. co-infections. This study emphasizes the clinical difficulties associated with assigning a specific clinical sign or haematological abnormality to a particular canine vector-borne disease.     

Serologic and molecular evidence of coinfection with multiple vector-borne pathogens in dogs from Thailand

Forty-nine dogs from Thailand were evaluated for serologic evidence of exposure or polymerase chain reaction (PCR) evidence of infection with vectorborne pathogens, including Ehrlichia sp. (Ehrlichia canis, Ehrlichia chaffeensis, Ehrlichia equi, and Ehrlichia risticii), Bartonella vinsonii subsp. berkhoffi (Bvb), spotted fever group (SFG) rickettsiae (Rickettsia rickettsii), Typhus group (TG) rickettsiae (Rickettsia canada, Rickettsia prowazekii, and Rickettsia typhi), and Babesia sp. (Babesia canis and Babesia gibsonii). All study dogs had at least 1 of 3 entry criteria: fever, anemia, or thrombocytopenia. By immunofluorescence antibody (IFA) testing, seroreactivity was most prevalent to E chaffeensis (74%) and E canis (71%) antigens, followed by E equi (58%), Bvb (38%), E risticii (38%), R prowazekii (24%), B canis (20%), R rickettsii (12%), R canada (4%), and B gibsonii (4%) antigens. There was 100% concordance between E canis IFA and Western blot immunoassay (WI) for 35 of 35 samples; 2 samples were IFA and WI reactive only to E equi antigens. By PCR amplification, 10 dogs were found to be infected with E canis, 5 with Ehrlichia platys, and 3 with B canis. Sequencing of PCR products was undertaken to compare Ehrlichia strains from Thailand to strains originating from the United States. Partial DNA sequence analysis confirmed infection with E canis and E platys, with identical 16S rRNA sequence alignment to E canis (U26740) and to E platys (M83801), as reported in GenBank. Partial E canis P28.1 and P28.2 amino acid sequences from Thai dogs were divergent from analogous sequences derived from North American E canis (AF082744) strains, suggesting that the Thai dogs were infected with a geographically distinct strain of E canis compared to North American strains. The results of this study indicate that dogs in Thailand have substantial exposure to vectorborne diseases and that coinfection with these pathogens may be common.     

Detection of Anaplasma platys and Babesia canis vogeli and their impact on platelet numbers in free-roaming dogs associated with remote Aboriginal communities in Australia

OBJECTIVE: To detect Anaplasma platys and Babesia canis vogeli infection, using polymerase chain reaction (PCR)-based assays, in free-roaming dogs associated with eight Aboriginal communities in remote areas of Australia and to determine the impact of infection through the assessment of platelet numbers. PROCEDURES: Blood samples from 215 dogs were screened by PCR for A platys and B canis vogeli using established genus-specific DNA primers for the 16S and 18S rRNA genes respectively. Both A platys DNA and B canis vogeli DNA were confirmed from the screening PCR either by sequencing or by the use of species-specific primers. Peripheral blood films from 92 of the 215 dogs were used to estimate platelet numbers through an indirect method. RESULTS: Of 215 dogs, 69 (32%) were positive for A platys, 22 (10%) for B canis vogeli and 24 (11%) for both. The two organisms were detected singularly and as coinfection in all communities. For the 92 dogs in which peripheral blood films were examined, the mean estimated platelet counts for the non-infected dogs was 318 x 10(9)/L, those infected with A platys alone was 256 x 10(9)/L, those with B canis vogeli alone was 276 x 10(9)/L and those infected with both parasites was 169 x 10(9)/L. In young dogs, infection produced significantly decreased mean platelet counts when compared to uninfected dogs. Thrombocytopenia (< 200 x 10(9)/L) was detected in 18 (51%) dogs infected with A platys alone, 3 (33%) dogs infected with B canis vogeli alone, 13 (72%) dogs coinfected, and 8 (27%) uninfected dogs. CONCLUSIONS: A platys and B canis vogeli infection, either singularly or together, was widespread in free roaming dogs associated with remote Aboriginal communities in the Northern Territory and north-western New South Wales. Moreover, both A platys and B canis vogeli infections were associated with a reduction in mean platelet numbers in dog populations, particularly in young dogs. The fact that 51% of dogs infected with A platys alone and 72% dogs coinfected were thrombocytopenic compared to 27% of uninfected dogs suggests that the organism alone or in combination with B canis vogeli has the potential to cause thrombocytopenia and perhaps contribute to a clinical bleeding disorder in infected dogs.     

Molecular and serological detection of Ehrlichia canis and Babesia vogeli in dogs in Colombia

Ehrlichiosis and babesiosis are tick-borne diseases, caused mainly by Ehrlichia canis and Babesia canis, respectively, with a worldwide occurrence in dogs, whose main vector is the brown-dog tick, Rhipicephalus sanguineus. The present work aimed to detect the presence of E. canis and Babesia sp. in 91 dog blood samples in Colombia, by molecular and serological techniques. We also performed sequence alignment to indicate the identity of the parasite species infecting these animals. The present work shows the first molecular detection of E. canis and B. vogeli in dogs from Colombia. Immunoglobulin-G (IgG) antibodies to E. canis and Babesia vogeli were found in 75 (82.4%) and 47 (51.6%) sampled dogs, respectively. Thirty-seven (40.6%) and 5 (5.5%) dogs were positive in PCR for E. canis and Babesia sp., respectively. After sequencing, amplicons showed 99% of identity with isolates of E. canis and B. vogeli. The phylogenetic trees based on 16S rRNA-Anaplasmataceae sequences and 18S rRNA-piroplasmid sequences supported the identity of the found E. canis and B. vogeli DNAs, respectively. The present work shows the first molecular detection of E. canis and B. vogeli in dogs in Colombia.     

Canine babesiosis in Slovenia: molecular evidence of Babesia canis canis and Babesia canis vogeli

Canine babesiosis, caused by intraerythrocytic Babesia spp., is a tick-borne disease of worldwide importance. No information on canine babesiosis has been documented in Slovenia. Therefore, 238 dogs admitted to the Small animal clinic in Ljubljana from the years 2000 to 2002 were tested for the presence of babesial parasites in the blood. Based on clinical, microscopic and molecular investigations, 14 dogs (5.9%) were determined as being infected with babesiae. Clinical signs relating to acute haemolysis, fever, anorexia, depression and haematological abnormalities such as anaemia and thrombocytopenia were noticed in most of the 14 infected dogs. The morphology of the parasites was indicative of Babesia canis infection. Two subspecies were detected, namely B. canis canis (11 dogs, 4.6%) and B. canis vogeli (3 dogs, 1.3%) using PCR and subsequent sequence analysis of portions of nns rRNA gene. In addition, based on nucleotide sequence analysis, the 11 isolates of B. c. canis could be subdivided into three groups, whereas the three B. c. vogeli isolates were genetically identical. The results of this study demonstrate the presence of canine babesiosis due to B. c. canis and B. c. vogeli in Slovenia.     

Prevalence of Ehrlichia canis infection in thrombocytopenic dogs from Rio de Janeiro, Brazil

BACKGROUND: Infection with Ehrlichia canis causes a highly variable, multisystemic disease in dogs. Nevertheless, many clinicians in Rio de Janeiro, Brazil, use the presence of only thrombocytopenia to make a presumptive diagnosis of E canis infection. OBJECTIVE: The objective of this study was to determine the prevalence of E canis in thrombocytopenic dogs from Rio de Janeiro, Brazil, using polymerase chain reaction (PCR). METHODS: Following DNA extraction of whole blood samples from 226 dogs, PCR assays were done using primers for rickettsial DNA (including Ehrlichia spp, Anaplasma platys and A phagocytophilum) and using E canis-specific primers (16S rRNA gene). Dogs were grouped as thrombocytopenic and nonthrombocytopenic based on platelet counts. The null hypothesis that there was no difference in the prevalence of E canis in these groups was rejected at P<.05. RESULTS: Thirty-six (32.1%) of the thrombocytopenic dogs and 4 (3.5%) of the nonthrombocytopenic dogs were positive for rickettsial gene sequences (P<.0001). Further, 30 (26.8%) of thrombocytopenic dogs and 4 (3.5%) nonthrombocytopenic dogs were positive for E canis-specific gene sequences (P<.0001). CONCLUSIONS: Although the prevalence of E canis infection was higher in thrombocytopenic dogs, less than one third of these dogs had demonstrable E canis infection. Thus, thrombocytopenia is not specific for the detection of E canis infection and should not be used solely to establish a diagnosis of canine ehrlichiosis, even in a geographic area with relatively high disease prevalence.     

New advances in molecular epizootiology of canine hematic protozoa from Venezuela, Thailand and Spain

The prevalence of hematozoan infections (Hepatozoon canis and Babesia sp., particularly Babesia canis vogeli) in canids from Venezuela, Thailand and Spain was studied by amplification and sequencing of the 18S rRNA gene. H. canis infections caused simultaneously by two different isolates were confirmed by RFLP analysis in samples from all the geographic regions studied. In Venezuela, blood samples from 134 dogs were surveyed. Babesia infections were found in 2.24% of the dogs. Comparison of sequences of the 18S rRNA gene indicated that protozoan isolates were genetically identical to B. canis vogeli from Japan and Brazil. H. canis infected 44.77 per cent of the dogs. A representative sample of Venezuelan H. canis isolates (21.6% of PCR-positives) was sequenced. Many of them showed 18S rRNA gene sequences identical to H. canis Spain 2, albeit two less frequent genotypes were found in the sample studied. In Thailand, 20 dogs were analyzed. No infections caused by Babesia were diagnosed, whereas 30 per cent of the dogs were positive to hematozoan infection. Two protozoa isolates showing 99.7-100% identity to H. canis Spain 2 were found. In Spain, 250 dogs were studied. B. canis vogeli infected 0.01% of the animals. The sequence of the 18S rRNA gene in Spanish isolates of this protozoa was closely related to those previously deposited in GenBank (> 99% identity). Finally, 20 red foxes were screened for hematozoans employing semi-nested PCR and primers designed to detect Babesia/Theileria. Fifty percent of the foxes were positive to Theileria annae. In addition, it was found that the PCR assay was able as well to detect Hepatozoon infections. Thirty five percent of the foxes were infected with two different H. canis isolates showing 99.8-100% identity to Curupira 1 from Brazil.     

Babesia canis canis and Babesia canis vogeli clinicopathological findings and DNA detection by means of PCR-RFLP in blood from Italian dogs suspected of tick-borne disease

The aims of this study were to determine the presence of Babesia spp. in blood samples from Italian dogs with clinical signs compatible with tick-borne diseases by means of PCR-restriction fragment length polymorphism (RFLP) and describe the clinicopathological findings of dogs with Babesia infection. We evaluated the majority of canine babesiosis cases by means of clinical history, physical examination, hematological, biochemical, serum electrophoresis, urinalysis and hemostatic tests. Forty-five out of 164 canine blood samples studied were positive to Babesia PCR-RFLP with the following results: Babesia canis canis (n=34) and Babesia canis vogeli (n=11). The majority of B. c. canis infections were detected in Northern Italy (29.1%; 30/103). B. c. vogeli cases were detected mainly in Central and Southern Italy (16.3%; 10/61). Only one B. c. vogeli was detected in Northern Italy (0.9%; 1/103). Three positive samples to B. c. canis and four positive samples to B. c. vogeli were selected for sequencing of a fragment of the 18S rRNA gene (410bp) for further molecular characterization. The sequence obtained from all seven dogs was 99/100% homologous to sequences from B. c. canis and B. c. vogeli, respectively, present in GenBank. Sixty-two percent of dogs infected with B. c. canis had recently travelled on a hunting trip to East European countries. The main acute clinical signs were dehydration, apathy, anorexia and fever. The majority of dogs infected with B. c. canis presented at initial clinical examination mild to severe thrombocytopenia, hyperfibrinogenemia, mild to moderate normocytic-normochromic non-regenerative anemia, hemolysis and neutropenia. The urinalysis showed hemoglobinuria in 13/19 dogs suggesting intravascular hemolysis. Dogs with B. c. canis infection had high levels of C-reactive protein. Hypoalbuminemia was present in 17/26 dogs. The 11 cases of B. c. vogeli infection did not present a homogenous clinicopathological pattern. B. c. vogeli infections were observed in young dogs causing hemolytic anemia and in adult/old does that frequently presented predisposing factors such as splenectomy or immunocompromised conditions. In conclusion, this study demonstrates the presence of B. c. canis and B. c. vogeli in Italian sick dogs and differences in clinicopathological pattern in these two species of B. canis.     

Application of 10% imidacloprid/50% permethrin to prevent Ehrlichia canis exposure in dogs under natural conditions

Canine monocytic ehrlichiosis (CME) caused by Ehrlichia canis is the most known canine tick-borne disease (TBD) spread throughout the world. Preventing tick bites is a priority to reduce the risk of TBDs and it was the aim of the present study to evaluate the efficacy of a combination of imidacloprid 10% and permethrin 50% (ImPer) (Advantix; Bayer AG, Germany) in a spot-on formulation to control CME under field conditions. On January-March 2005, 845 dogs from two kennels in southern Italy (kennels of Bari (KB)- and Ginosa (KG)), with a history of tick infestation were initially tested by serology and PCR assay for E. canis infection. Data on Leishmania infantum infection were also available from a previous study carried out on the same dog population. One hundred twenty-six dogs (14.9%) presented anti-E. canis antibodies with a relative prevalence of 15.6% (n=65 dogs in KB) and 14.2% (n=61 dogs in KG). Five hundred thirty-five animals found negative both for E. canis and L. infantum infections were enrolled in three groups (Group A--treated with ImPer once a month; Group B--treated every 2 weeks; and Group C--untreated control animals) and monitored for E. canis infection by serology and PCR in November 2005 (first follow-up) and in March 2006 (second follow-up). The E. canis infection was serologically revealed, at the first and/or second follow-up, in 26 animals from Group C in KB and KG (mean incidence density rate (IDR), 13.24%) while in none of the animals from Group A (KB and KG) and only in one animal from Group B (IDR 1.13%) in KG. The final protection efficacy of ImPer ranged from 95.57% to 100% in Groups B and A. At PCR only 15 dogs from KG were positive for Rickettsiales only at the first follow-up and at the sequence analysis two (both in Group C) revealed 100% homology with E. canis sequences while 13 with Anaplasma platys. Four out of 13 A. platys PCR-positive dogs were also seropositive for E. canis at one or both follow-ups. ImPer, by virtue of its repellent and acaricidal activity against ticks, has been shown to be efficacious to prevent E. canis infection in treated dogs living under natural conditions in endemic areas.     

Babesia canis canis and Babesia canis vogeli infections in dogs from northern Portugal

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.     

Detection and molecular characterization of Babesia canis vogeli from naturally infected dogs and Rhipicephalus sanguineus ticks in Tunisia

Canine babesiosis, caused by intra-erythrocytic Babesia, is a tick-borne disease of worldwide importance. No information on canine babesiosis has been documented in Tunisia. Detection and analysis of Babesia species from naturally infected dogs and ticks recovered from dogs were attempted by reverse line blot hybridization and nucleotide sequence analysis based on 18S rRNA gene. Out of 180 blood samples collected from domestic dogs in 4 villages situated in different bioclimatic zones, 12 were positive for Babesia canis vogeli. In addition, a total of 160 Rhipicephalus sanguineus were analysed; only one male was infected by B. canis vogeli. This is the first report on the detection of DNA belonging to B. canis vogeli in domestic dogs and in R. sanguineus in Tunisia.     

Epidemiological survey of Anaplasma platys and Ehrlichia canis using ticks collected from dogs in Japan

Detection of Anaplasma platys and Ehrlichia canis in ticks recovered from dogs in Japan was attempted using a species-specific nested PCR based on the 16S rRNA gene. A total of 1211 ticks recovered from 1211 dogs from all over Japan were examined for A. platys and E. canis. Four tick samples from Fukushima, Miyazaki and Kagoshima Prefectures recovered from four different dogs showed a positive reaction for A. platys. Although the four dogs did not show any clinical signs and no blood examination data were available, it is possible that A. platys has already been spread widely in Japan. No positive reactions were observed in any ticks examined for E. canis.     

Antibodies to Ehrlichia canis, Ehrlichia platys, and Spotted Fever Group Rickettsiae in Louisiana Dogs

Antibodies to Ehrlichia canis, Ehrlichia platys, and spotted fever group (SFG) rickettsiae were detected by indirect immunofluorescence in sera from 27 ill individually owned thrombocytopenic dogs (platelet concentrations less than 200,000 platelets/microliters) and 59 healthy kenneled dogs located in southern Louisiana. Platelet concentrations less than 100,000 platelets/microliters were detected in 63% of ill thrombocytopenic dogs and 6.8% of healthy kennel dogs. One ill thrombocytopenic dog had intracytoplasmic E platys morulae detected within platelets. The prevalence of increased serum antibody titers to E canis and E platys was 25.9% and 40.7% for the ill thrombocytopenic dogs and 20.3% and 54.2% for the healthy kennel dogs, respectively. All dogs with seropositivity to E canis had increased antibody titers of greater than or equal to 1:100 to E platys. Simultaneous examination of increased serum antibody titers (greater than or equal to 1:64) to four SFG rickettsiae indicate that Rickettsia rhipicephali and Rickettsia montana accounted for the majority of the antibodies detected in these dogs. Of 86 dogs tested, 44.2% were seronegative to E canis, E platys, and SFG rickettsiae.     

Detection of Ehrlichia canis by PCR in different tissues obtained during necropsy from dogs surveyed for naturally occurring canine monocytic ehrlichiosis

A molecular study for the detection of Ehrlichia canis was carried out on tissues obtained at necropsy from randomly selected dogs with the intention of investigating naturally-occurring canine ehrlichiosis. The tissues evaluated for the presence of E. canis included lymph nodes, spleen, liver, bone marrow, and blood. Eight of the 18 dogs included were found to be positive for E. canis by polymerase chain reaction (PCR) and sequencing of the 16S rRNA gene. Two dogs were positive for Anaplasma platys of which one dog was co-infected with E. canis and A. platys. Blood (5/8) and lymph nodes (5/8) were the tissues found to yield the highest number of positive E. canis PCR results with 7/8 dogs positive in the blood or lymph node. E. canis and A. platys DNA could be amplified by PCR when tissue samples were obtained 72h after the time of death.     

Chronic canine ehrlichiosis (Ehrlichia canis): a retrospective study of 19 natural cases

Nineteen dogs from Greece with chronic ehrlichiosis were studied. The dogs exhibited bicytopenia or pancytopenia, bone marrow hypoplasia, seroreactivity to Ehrlichia canis (E. canis) antigens, and had no history of drug or radiation exposure. Anorexia, depression, severe bleeding tendencies, hypoalbuminemia, and increased serum alanine aminotransferase activity were also hallmarks of the disease. All these animals eventually died, irrespective of the treatment applied. Some dogs were also serologically positive for Rickettsia conorii, Leishmania infantum (L. infantum), and Bartonella vinsonii subspp. berkhoffii. Polymerase chain reaction testing of bone marrow samples revealed E. canis, Anaplasma phagocytophilia, Anaplasma platys, and L. infantum in some dogs. Concurrent infections did not appear to substantially influence the clinical course and final outcome of the chronic canine ehrlichiosis.     

Assessment of primers designed for the subspecies-specific discrimination among Babesia canis canis, Babesia canis vogeli and Babesia canis rossi by PCR assay

Canine babesiosis is an infectious disease caused by either Babesia gibsoni or Babesia canis protozoans. The latter is also classified under three different phylogenetic groups, referred to as subspecies B. canis canis, B. canis vogeli and B. canis rossi. The objective of the present study was to validate and standardize a PCR assay to discriminate the organisms at the subspecies level. First, the reference sequences of the 18S rRNA, 5.8S rRNA and 28S rRNA genes, including the internal transcribed spacer 1 (ITS1) and 2 (ITS2) of the most common species and subspecies of the genus Babesia were retrieved from the GenBank database. Subspecies-specific primers (BAB3, BAB4 and BAB5) and one genus-specific primer were designed from the alignment of the sequences. The PCR assays were evaluated in three different combinations of primer pairs in order to assure complete specificity for each reaction. The results of the tests had demonstrated effectiveness of the novel primer pairs BAB1/BAB3, BAB1/BAB4 and BAB1/BAB5 for the amplification of the subspecies-specific target fragments of 746 bp (B. c. canis), 546 bp (B. c. vogeli) and 342 bp (B. c. rossi) by PCR. The original enzymatic amplification assays with novel primers reported in this paper were confirmed to be a reliable tool for the specific discrimination among B. canis subspecies by single-step PCR assays.     

Use of a Real Time PCR for detecting subspecies of Babesia canis

This paper reports the development and use of a Real Time PCR for detection of Babesia canis canis, B. canis rossi, and B. canis vogeli in endemic areas of Brazil. The sequences of the internal transcribed spacer (ITS) of several organisms were aligned and five primers and four probes were designed for amplification of a fragment (around 125 bp) which differentiates subspecies of B. canis. Blood samples collected from dogs living in farms in three distinct rural regions within the State of Minas Gerais (Lavras, Belo Horizonte and Nanuque) were tested. Blood samples had been collected during a dry season (Lavras, n=100; Belo Horizonte, n=50; Nanuque, n=102); the dogs were re-sampled in the subsequent rainy season (Lavras, n=71; Belo Horizonte, n=29; Nanuque, n=66). From each sample, DNA was extracted and Giemsa stained smears were microscopically examined for direct detection of Babesia parasites. B. canis vogeli was the only subspecies found, with an overall prevalence of 9.9% during the dry season and 10.8% during the rainy season. Dogs living in Nanuque and Belo Horizonte showed significantly higher prevalence rates than those living in Lavras (13.7%, 12.0% and 5.0%, respectively). The Real Time PCR developed proved to be appropriate to detect B. canis subspecies in endemic areas.     

Serologic prevalence of Dirofilaria immitis,Ehrlichia canis,and Borrelia burgdorferi infections in Brazil

Dogs infected with Dirofilaria immitis, Ehrlichia canis, or Borrelia burgdorferi may show nonspecific clinical signs or may be asymptomatic. In Brazil, E. canis and D. immitis infections are frequently diagnosed based on the presence of classical signs; however, serologic tests are seldom performed to confirm the presence of infection. To estimate the seroprevalence of these three canine diseases in Brazil, 2,553 dogs presented at veterinary practices for various tests, routine treatments, or examinations were evaluated by an in-office commercial ELISA test kit (SNAP 3Dx, IDEXX Laboratories). Each dog was examined by the veterinarian, and a whole-blood sample was collected and immediately tested for the simultaneous detection of B. burgdorferi and E. canis antibodies and D. immitis antigen. D. immitis infection was detected in 51 dogs (2.0%) and E. canis antibodies were present in 505 dogs 19.8%). Only one dog tested positive for B. burgdorferi antibodies.     

Molecular survey of Babesia canis in dogs in Nigeria

An epidemiological study of Babesia canis in dogs in Nigeria was performed. Four hundred blood samples collected from dogs in Nigeria were investigated using nested PCR and sequence analysis. On nested PCR screening, nine samples (2.3%) produced a band corresponding to a 698-bp fragment indicative of B. canis infection. Sequence analysis of the PCR products identified eight samples (2.0%) as B. canis rossi and the ninth (0.3%) as B. canis vogeli. This is the first report of the prevalence of B. canis rossi and B. canis vogeli in dogs in Nigeria.     

Ehrlichial infection in Cameroonian canines by Ehrlichia canis and Ehrlichia ewingii

Ehrlichia chaffeensis and Ehrlichia ewingii are agents of emerging human ehrlichioses in North America and are transmitted primarily by Amblyomma americanum ticks, while Ehrlichia canis is the globally distributed cause of canine monocytic ehrlichiosis (CME) and is transmitted by the brown dog tick, Rhipicephalus sanguineus. Although E. canis and Ehrlichia ruminantium are endemic in Africa, the presence of ehrlichial agents in dogs and ticks in Cameroon has not been investigated. The objective of this study was to determine the prevalence of ehrlichial infections in Cameronian dogs using a combination of serologic and molecular methods. Peripheral blood was collected, clinical signs and the presence or absence of ticks on dogs (n=104) presenting for various reasons at local veterinary clinics around the Mount Cameroon region were noted. IFA identified 33 dogs (32%) with antibodies reactive with E. canis, and reactivity of these sera with all major E. canis antigens (200, 140, 95, 75, 47, 36, 28, and 19-kDa) was confirmed by immunoblotting. Multicolor real-time PCR detected ehrlichial DNA (E. canis (15) and E. ewingii (2)) in 17 dogs (16.3%), all of which had attached ticks at time of presentation. The dsb amplicons (378 bp) from E. canis and E. ewingii were identical to gene sequences from North American isolates. This study identifies canine ehrlichiosis as a prevalent unrecognized cause of disease in Cameroonian canines.