General Veterinary

Abstract Background Hemotropic mycoplasmas or hemoplasmas are bacteria that attach to the erythrocyte surface and cause bovine hemoplasmosis. Two species, Mycoplasma wenyonii and Candidatus Mycoplasma haemobos, have been identified and shown to be distributed worldwide. However, there is currently no information available on hemoplasmas in cattle in the Republic of Korea. The aim of this study was to investigate the presence of hemoplasmas in Korean native cattle and to evaluate the association between hemoplasma infection and anemia. Methods One farm was selected, at which blood samples were collected from 104 Korean native cattle [grazing cattle (n = 89) and housed cattle (n = 15)]. Hemoplasmas were detected via polymerase chain reaction analysis and complete blood counts were also performed. Results The overall prevalence of hemoplasmas was 34% (35/104); 20.2% (21/104) for M. wenyonii, 3.8% (4/104) for C. M. haemobos, and 9.6% (10/104) for co-infection. Candidatus Mycoplasma haemobos was detected only in grazing cattle. Of red blood cell (RBC) parameters, C. M. haemobos-infected cattle had lower RBC and hematocrit, and higher mean cell volume than hemoplasma-negative cattle, although none of these differences were statistically significant. This is the first study to report the occurrence of M. wenyonii and C. M. haemobos. Mycoplasma wenyonii is more prevalent than C. M. haemobos in Korean native cattle. The results did not show an association between hemoplasma infection and anemia. Conclusions Considering the infection rate of hemoplasmas shown in this study, further studies, such as on the pathogenicity and clinical significance of hemoplasmas are necessary.

The recent emergence of anaplasmosis in camels has raised global interest in the pathogenicity and zoonotic potential of the pathogen causing it and the role of camels as reservoir hosts. In the United Arab Emirates (UAE), molecular studies and genetic characterization of camel-associated Anaplasma species are limited. This study aimed to characterize molecularly Anaplasmataceae strains circulating in dromedary camels in the UAE. Two hundred eighty-seven whole-blood samples collected from dromedary camels across regions of the Abu Dhabi Emirate were received between 2019 and 2023 at the Abu Dhabi Agriculture and Food Safety Authority (ADAFSA) veterinary laboratories for routine diagnosis of anaplasmosis. The animals were sampled based on field clinical observation by veterinarians and their tentative suspicion of blood parasite infection on the basis of similar clinical symptoms as those caused by blood parasites in ruminants. The samples were screened for Anaplasmataceae by PCR assay targeting the groEL gene. Anaplasmataceae strains were further characterized by sequencing and phylogenetic analysis of the groEL gene. Thirty-five samples (35/287 = 12.2%) tested positive for Anaplasmataceae spp. by PCR assay. Nine positive samples (9/35 = 25.7%) were sequenced using groEL gene primers. GenBank BLAST analysis revealed that all strains were 100% identical to the Candidatus A. camelii reference sequence available in the GenBank nucleotide database. Phylogenetic analysis further indicated that the sequences were close to each other and were located in one cluster with Candidatus A. camelii sequences detected in Saudi Arabia, Morocco, and the UAE. Pairwise alignment showed that the UAE sequences detected in this study were completely identical and shared 100% identity with Candidatus A. camelii from Morocco and Saudi Arabia and 99.5% identity with Candidatus A. camelii from the UAE. This study demonstrates the presence of Candidatus A. camelii in UAE dromedary camels. Further critical investigation of the clinical and economical significance of this pathogen in camels needs to be carried out.

Abstract Background The appearance of the novel porcine haemotrophic mycoplasma (HM) species ‘Candidatus Mycoplasma haemosuis’ was reported in apparently healthy but also in clinically sick animals in China, Korea and in a case report from Germany. Outside of Asia, however, nothing further is known about the frequency of ‘Ca. M. haemosuis’ in pigs to date. To investigate the distribution of this novel HM species in Germany, fattening pigs, sows and pre-suckling piglets were examined using a herein developed quantitative real-time PCR assay (qPCR). Because the piglets were sampled before the first colostrum uptake, additional information on a possible vertical transmission from dams to their offspring was obtained. Results Our novel qPCR assay successfully detected ‘Ca. M. haemosuis’ in all blood samples from the ‘Ca. M. haemosuis’-infected pigs. No cross-reactivity was detected when DNA from non-target Mycoplasma spp. and other bacterial species representing 105 bacteria/reaction were used as a template. The lower limit of detection of the qPCR was thus 10 gap gene copies per reaction and 2.5 x 103 genome equivalents (GE) per mL blood. ‘Candidatus M. haemosuis’ was detected by this qPCR in blood samples from a total out of 6.25% sows (13/208), 4.50% pre-suckling piglets (28/622) and 17.50% fattening pigs (35/200). On farm level, 3 out of 21 piglet producing farms (14.28%) and 9 out of 20 fattening farms (45.00%) were positive for ‘Ca. M. haemosuis’. Co-infections with M. suis were evident in all age groups. Conclusion ‘Candidatus M. haemosuis’ infection is present in German pig farms and the detection of the novel porcine HM species in piglets immediately after birth before colostrum intake indicates vertical transmission. The novel qPCR assay specific for ‘Ca. M. haemosuis’ described herein will be a prerequisite for future studies on the prevalence, epidemiology as well as the clinical and economic impact of ‘Ca. M. haemosuis’ infections.

This study presents the molecular detection of Candidatus Rickettsia andeanae and Ehrlichia sp. in Amblyomma pseudoconcolor Aragão, 1908 (Acari: Ixodidae) collected on a large hairy armadillo (Chaetophractus villosus (Desmarest, 1804)). On 12 October 2020, a specimen of C. villosus was found dead on the road in Río Negro province, Argentina. Molecular detection of Rickettsia and Ehrlichia agents was performed amplifying the gltA and 16S rRNA gene, respectively. One tick, determined morphologically and genetically as A. pseudoconcolor, was collected on C. villosus. The rickettsial agent detected in A. pseudoconcolor was identified as Candidatus Rickettsia andeanae. The Ehrlichia sp. strain showed high sequence similarity to different uncultured Ehrlichia sp. detected in horses, capybaras and Ixodes ornithorhynchi from Nicaragua, Brazil and Australia, respectively. The results of this study and previous findings suggest that A. pseudoconcolor may be a potential vector of some Rickettsia and Ehrlichia bacteria of unknown pathogenicity.

Health monitoring programs in animals used as experimental models are essential, since only disease-free subjects are considered suitable for research purposes. In laboratory-kept animals, hemoplasmas have been described as an important confounding variable. Different hemoplasma species have been detected infecting non-human primates (NHP) from Brazil. However, the occurrence of hemoplasma species in laboratory-kept NHP in Brazil has not-yet been assessed. Accordingly, this study aimed (i) to screen laboratory-kept rhesus monkeys for hemoplasmas, (ii) to verify if any of the hemoplasma-positive animals demonstrate hematological abnormalities, and (iii) to assess the genotype diversity of hemoplasma species in NHP from Brazil. Five out of eight (62.5%; 95% CI: 3.05–8.63) rhesus monkeys tested positive for hemotropic Mycoplasma spp. by PCR. Sequencing, phylogenetic, distance, and genotype diversity analyses of partial 16S rRNA gene demonstrate that rhesus monkeys were infected by ‘Candidatus Mycoplasma haematomacacae’ (formerly ‘Candidatus Mycoplasma haemomacaque’). Assessments of partial 16S rRNA diversity of hemoplasma species in NHP suggest that at least four genetically diverse groups may occur in Brazil. Although no hematological abnormalities were demonstrated in rhesus monkeys evaluated herein, future studies are needed to elucidate the influence of ‘Ca. M. haematomacacae’ as a confounding variable on research studies.

Abstract Background In addition to Mycoplasma haemocanis and Candidatus Mycoplasma haematoparvum, a few hemoplasma species that mainly infect other livestock have been detected in dogs. ‘Candidatus Mycoplasma haemobos’ (Ca. M. haemobos) has been found in a variety of animals in China. The present study was aimed to investigate the occurrence of ‘Ca. M. haemobos’ infections in dogs and ticks collected from the Henan province, China. Results Overall, 55 dog blood samples and 378 ticks on skins were collected from anemic and healthy dogs, and these samples were subjected to PCR, sequence analysis, and identification. The results showed that Haemaphysalis longicornis (266) and Rhipicephalus (Boophilus) microplus (112) were the only two parasitic ticks on dogs. Molecular detection revealed that 163 M. haemocanis, 88 ‘Ca. M. haemobos’ and 32 Anaplasma platys positive amplicons could be amplified from dogs, H. longicornis and R. (B.) microplus. In addition, co-infections (M. haemocanis + A. platys and ‘Ca. M. haemobos’+ A. platys) could be also detected. Conclusions To the best of our knowledge, this is the first molecular evidence of ‘Ca. M. haemobos’ natural infection in dogs and tick species identified as H. longicornis and R. (B.) microplus from China.