Rhipicephalus bursa is a common tick parasite of small-to-medium size ungulates, principally in warm, temperate, and subtropical areas. Although common in livestock and showing a wide geographic distribution, its epidemiological role in tick-borne bacterial disease is barely known. This study addressed the knowledge gap and aimed to screen for the presence of Anaplasmataceae and spotted fever group (SFG) Rickettsia species in R. bursa ticks collected from domestic animals in Romania, Eastern Europe. A total of 64 pools of R. bursa ticks collected from small ungulates were tested by PCR for Anaplasmataceae DNA presence using group-specific primers. Specific testing was performed for Anaplasma marginale/A. centrale/A. ovis, A. platys, A. phagocytophilum, Ehrlichia canis, and SFG Rickettsia. The positive samples were purified and sequenced, and sequences analysis was used to identify the species and to confirm the PCR results. The only pathogen identified in this study was E. canis. The obtained sequences confirmed the PCR results. The presence of E. canis in R. bursa in Romania and in ticks from sheep was shown for the first time in this study. Based on these findings, it may be presumed that the E. canis DNA originated from ticks; however, the vectorial role of R. bursa (and other arthropod species) in the transmission of E. canis should be proved experimentally.

A total of 103 blood samples from pet dogs around Ipoh were screenedfor common blood protozoa. A total of 14 samples were found positive for Erhlichia canis and one sample was found positive for microfilaria of Dirofilaria immitis. Both these diseases are transmitted by vectors; ticks (Rhipicephalus sangiuneus) and mosquitoes respectively. In the hot and wet tropical environment where vectors are abundant, pet care, hygiene and regular screening will help veterinarians detect these infections early to facilitatetreatment.

Objective: To determine the prevalence of perinuclear antineutrophil cytoplasmic autoantibodies (pANCA) in dogs with confirmed or suspected immune-mediated hemolytic anemia (IMHA) or dogs infected with various vector-borne pathogens, including Rickettsia rickettsii, Bartonella henselae, Bartonella vinsonii subsp berkhoffii, Ehrlichia canis, Borrelia burgdorferi, and Leishmania infantum. Animals: 55 dogs with confirmed or suspected IMHA, 140 dogs seroreactive for vector-borne pathogens, and 62 healthy dogs and dogs seronegative for vector-borne pathogens. Procedures: Samples were allocated to subgroups on the basis of the health status of the dogs and the degree of seroreactivity against various vector-borne pathogens. Serum samples were tested retrospectively via indirect immunofluorescence assay to determine pANCA status. Results: 26 of 55 (47%) dogs with confirmed or suspected IMHA and 67 of 140 (48%) dogs seroreactive for vector-borne pathogens had positive results when tested for pANCA. Serum samples with the highest antibody concentrations against L infantum antigen had the highest proportion (28/43 [65%]) that were positive for pANCA. One of 20 (5%) dogs seronegative for tick-borne pathogens and 8 of 22 (36%) dogs seronegative for L infantum had positive results for pANCA. One of 20 (5%) healthy dogs had serum antibodies against pANCA. Conclusions and Clinical Relevance: pANCA were detected in a high percentage of dogs with IMHA and vector-borne infectious diseases. Therefore, pANCA may be a relatively nonspecific marker for dogs with inflammatory bowel disease, although they could represent a biomarker for immune-mediated diseases and infections.

The antigenic profile of Ehrlichia canis, E risticii, E sennetsu, and E equi was investigated by the use of protein (western) immunoblot technique. Results of analysis of serum from acutely and chronically infected animals indicated that the 4 Ehrlichia species share a unique 25-kD polypeptide in addition to other peptides. Immune sera from dogs inoculated with E canis recognized a wide range of E canis polypeptide antigens, as determined by western blot analysis. A larger number of E sennetsu polypeptides were detected when homologous antiserum and antiserum to E equi were used. The latter antiserum did not recognize antigens of E canis or E risticii. Antisera to E canis, E risticii, and E sennetsu detected E equi antigens. Data indicate that a 25-kD protein is a common antigen among the species of the genus Ehrlichia and that the ascending order of abundance of immunodominant determinants in the 4 species of Ehrlichia studied would be: E risticii leads to E equi leads to E sennetsu leads to E canis. Implications of these findings for diagnosis of ehrlichial infections and prophylaxis are evident.

OBJECTIVE To compare the performance of 5 synthetic peptide–based ELISAs with that of 3 commercially available immunofluorescent assays (IFAs) for serologic diagnosis of anaplasmosis and ehrlichiosis in dogs. SAMPLE A convenience set of 109 serum samples obtained before and at various times after inoculation for 23 dogs that were experimentally infected with Anaplasma phagocytophilum, Anaplasma platys, Ehrlichia canis, Ehrlichia chaffeensis, or Ehrlichia ewingii and 1 uninfected control dog in previous studies. PROCEDURES All serum samples were assessed with 5 synthetic peptide–based ELISAs designed to detect antibodies against A phagocytophilum, A platys, E canis, E chaffeensis, and E ewingii and 3 whole organism–based IFAs designed to detect antibodies against A phagocytophilum, E canis, and E chaffeensis. The species-specific seroreactivity, cross-reactivity with the other tick-borne pathogens (TBPs), and diagnostic sensitivity and specificity were calculated for each assay and compared among assays. RESULTS All serum samples obtained from dogs experimentally infected with a TBP yielded positive results on a serologic assay specific for that pathogen. In general, sensitivity was comparable between ELISAs and IFAs and tended to increase with duration after inoculation. Compared with the IFAs, the corresponding ELISAs were highly specific and rarely cross-reacted with antibodies against other TBPs. CONCLUSIONS AND CLINICAL RELEVANCE Results suggested that peptide-based ELISAs had enhanced specificity relative to whole organism–based IFAs for detection of antibodies against Anaplasma and Ehrlichia spp, which should facilitate accurate diagnosis and may help detect dogs coinfected with multiple TBPs.

Ranked among the top threats to conservation worldwide, infectious disease is of particular concern for wild canids because domestic dogs (Canis familiaris) may serve as sources and reservoirs of infection. On British Columbia’s largely undeveloped but rapidly changing central and north coasts, little is known about diseases in wolves (Canis lupus) or other wildlife. However, several threats exist for transfer of diseases among unvaccinated dogs and wolves. To gain baseline data on infectious agents in this area, including those with zoonotic potential, we collected blood and stool samples from 107 dogs in 5 remote communities in May and September 2007. Serology revealed that the dogs had been exposed to canine parvovirus, canine distemper virus, Bordetella bronchiseptica, canine respiratory coronavirus, and Leptospira interrogans. No dogs showed evidence of exposure to Ehrlichia canis, Anaplasma phagocytophilum, Borrelia burgdorferi, Dirofilaria immitis, or Cryptococcus gattii. Of 75 stool samples, 31 contained at least 1 parasitic infection, including Taeniid tapeworms, the nematodes Toxocara canis and Toxascaris leonina, and the protozoans Isospora sp., Giardia sp., Cryptosporidium sp., and Sarcocystis sp. This work provides a sound baseline for future monitoring of infectious agents that could affect dogs, sympatric wild canids, other wildlife, and humans.

This study was conducted to survey of Ehrlichia (E.) canis and Borrelia (B.) burgdorferi antibodies among clinically healthy German shepherd dogs (116 females and 120 males) using a ELISA kit (SNAP 3Dx; IDEXX Laboratories, USA) in Korea. Whole blood samples are collected from the 236 dogs and are tested to detect E. canis and B. burgdorferi antibodies by using ELISA kit (SNAP 3Dx; IDEXX Laboratories, USA). Confidence interval comparisions revealed that dogs of 4-6 years have higher prevalence with a seropositive result (CI = 0.17 - 0.45) in E. canis than the other age groups but there are no differences among age groups in B. burgdorferi.

Canine granulocytic ehrlichiosis was diagnosed in 37 dogs by finding ehrlichial morulae in 0.1 to 26.2% of their blood neutrophils and eosinophils. All 37 dogs had clinical signs of arthritis or muscular stiffness. Titer to Ehrlichia canis was determined in sera from 31 of the 37 dogs; 25 dogs had titer ranging from 1:20 to 1:5,120. In the other 6 dogs, titer to E canis was < 1:10. The most common hematologic abnormality in these dogs, other than rickettsiemia, was thrombocytopenia. Granulocytes infected with ehrlichial organisms were not found in another 10 dogs that had clinical signs of arthritis or muscular stiffness. Of these 10 dogs, 3 had titer to E canis ranging from 1:40 to 1:320. Titer in the other 7 dogs was < 1:10. Ehrlichial morulae were not found in the granulocytes of 18 healthy dogs. Of these 18 dogs, 9 had titer to E canis ranging from 1:20 to 1:5,120. Titer in the other 9 dogs was < 1:10. Titer to Borrelia burgdorferi was determined in dogs with granulocytic ehrlichiosis, arthritic dogs without detected rickettsiemia, and in healthy dogs. Low titer determined by 2 laboratories was considered to be nonspecific reaction in all 3 groups of dogs and, thus, did not indicate that the arthritic disorders were attributable to canine borreliosis.

Ehrlichia chaffeensis, the newly recognized agent of human ehrlichiosis, is closely related to E canis, the causative agent of canine ehrlichiosis. Eight pups were inoculated IV with E chaffeensis-, or with E canis-infected DH82 cells, or organisms released from these host cells. Two additional pups served as nonexposed controls. Marked thrombocytopenia was observed in the E canis-infected pups, but not in those infected with E chaffeensis. Homologous serologic response was observed in the E chaffeensis-exposed pups by postinoculation day (PID) 14 and in the E canis-exposed pups by PID 21. Ehrlichia chaffeensis and E canis were reisolated from the respective inoculated pups on each of 8 attempts from PID 7 to 26. One E chaffeensis-exposed pup that was challenge exposed with E canis via blood transfusion, developed fever, anorexia, and thrombocytopenia, suggesting lack of cross protection against E canis.