Prevalence of hemoplasma infection among cattle in the western part of Japan

Hemopathogens in naturally infected bovine fetuses in Brazil

The transplacental transmission of parasites and hemoparasites is crucial for understanding the epidemiology of diseases. This study aimed to assess the prevalence of hemopathogens in bovine fetuses at various gestational periods. Samples were obtained from a slaughterhouse in the state of Minas Gerais, Brazil, and a total of 236 fetuses were collected. DNA extracted from blood samples (145) and organ samples (a pool of brain and spleen) (236) underwent a nested PCR (nPCR) assay to detect Babesia spp., Theileria spp., Trypanosoma vivax, Anaplasma marginale, Anaplasma bovis, Anaplasma phagocytophilum, Ehrlichia minasensis, and hemotropic Mycoplasma spp. Additionally, serological analysis of 145 plasma samples was conducted using the indirect fluorescent antibody test-IFAT to detect IgG against Babesia bovis, Babesia bigemina, A. marginale, and Trypanosoma vivax. The observed prevalence of transplacental transmission was 19.3 %, 6.2 %, 42.7 % and 2.7 %, for A. marginale, B. bigemina, 'Candidatus M. haemobos', and Mycoplasma wenyonii, respectively. The prevalence of A. marginale by gestational trimester was 16 % (13/81) in the second trimester and 23 % (14/60) in the third trimester, with no positive samples in the first trimester. Regarding the species B. bovis and B. bigemina, all evaluated animals tested negative by nPCR, and no serological evidence for B. bovis was found by the IFAT. Babesia bigemina demonstrated an overall seroprevalence of 6.2 % (9/145), with 4.8 % (7/145) in the last trimester and 1.3 % (2/145) in the second trimester of pregnancy. In total, 42.7 % (62/145) of blood samples were positive for 'Candidatus M. haemobos', with 42 % (34/81) in the middle trimester, and 43 % (26/60) in the final trimester of pregnancy. Mycoplasma wenyonni was detected in 2.7 % (4/145) blood samples, all in coinfection with 'C. M. haemobos'. The prevalence by pregnancy trimester was 25 % (1/4) in the first trimester; 1.2 % (1/81) in the second trimester and 3.3 % (2/60) in the third trimester of pregnancy. Hemopathogen DNA was detected in fetus blood samples but not the brain or spleen samples. All the samples were negative for T. vivax, Theileria spp., Anaplasma spp. and Ehrlichia spp. Overall, in this study, approximately 70 % of fetuses were positive for one or more of the studied parasites. No significant associations were observed between pairs of pathogens, except 'C. M. haemobos' and A. marginale.

Apparent prevalence of hemotropic mycoplasma in dairy calves and replacement heifers on Michigan farms

The bovine hemoplasmas include Mycoplasma wenyonii and Candidatus Mycoplasma haemobos, which are increasingly recognized as infecting cattle throughout the world. Infection with hemotropic mycoplasma has been reported to be widespread in mature dairy cows, but little is known about its prevalence in calves and heifers. The objective of this study was to investigate the prevalence and dynamics of infection with M. wenyonii and C. M. haemobos in calves and replacement heifers on Michigan dairy farms and assess the potential associations between infection status and hematological values. The study was designed as a prospective cross-sectional study with a longitudinal component. A convenience sample of 11 farms agreed to participate and were visited twice between March and September 2022. During the first farm visit, researchers collected blood samples from up to 94 animals per farm distributed among newborn and preweaning calves (n ≤ 31), weaned calves (n = 21), pre-breeding heifers (n = 21), and pregnant heifers (n = 21). During the first visit, blood samples (n = 174) were also collected from a convenience sample of mature cows to confirm the herd infection status. The same calves and heifers were sampled again ∼95 d (±3.0) later. During the first visit, blood samples were collected from 797 calves and replacement heifers, whereas 675 samples were collected during the second visit due to the inability to locate some animals. Detection of M. wenyonii and C. M. haemobos was based on results of real-time PCR. The hematocrit was determined using microcentrifugation, and the concentration of leukocytes using an automated cell counter. In all herds, most mature cows that were sampled tested positive for infection. The within-herd apparent prevalence of hemoplasma in calves and replacement heifers was 100% for both M. wenyonii and C. M. haemobos. The apparent prevalence of hemoplasma in youngstock was associated with age. In calves that were 1 to 6 mo old, the prevalence of infection was 6% to 8% but sharply increased to 31% by 8 mo of age. In older animals, the prevalence remained high, and was almost 100% in animals greater than 17 mo of age. Based on calves and heifers sampled twice, the cumulative incidence varied widely among herds, ranging from 3.7% to 96.0%, and increased with the age of the animals. We found no difference in hematocrit or number of lymphocytes, monocytes, neutrophils, or total leukocytes based on infection status. The number of eosinophils was greater in infected animals. This is the first study to report the prevalence of hemoplasmas in calves and replacement heifers in the United States. It indicates that young calves can be infected with hemoplasmas, but the rate of infection is low. The likelihood of infection increases as animals age, with a notable rise in the proportion of infected heifers occurring by 8 mo old, and the prevalence eventually reaching nearly 100% in older animals. Once infected, heifers appear to remain chronic carriers. Hemoplasma infection alone does not usually lead to the development of clinical signs, and most of the animals remain apparently healthy.

Graduate Student Literature Review: Hemotropic mycoplasmas in cattle

The objective of this narrative literature review is to better understand bovine hemoplasmosis, an emerging disease that threatens dairy animal health. Several species of hemotropic mycoplasma are known to infect both animals and humans, and Mycoplasma wenyonii and Candidatus Mycoplasma haemobos are the species that infect red blood cells of cattle. These microorganisms are associated with clinical signs in dairy cattle, but the effects of infection on health and productivity of dairy cows are poorly understood. In this paper, we review information about the epidemiology of bovine hemoplasmosis in different countries, including clinical signs associated with hemoplasmosis in cattle, methods of diagnosis, treatment, possible routes of transmission, risk factors for infection, and disease progression. Although hemoplasmas have been reported to infect cattle in many countries, and methods used to detect these organisms have improved, numerous gaps in knowledge were identified. The pathogenesis of the disease and potential effect on animal health and productivity remain unclear. With this review, we seek to contribute to the understanding of hemoplasmosis in cattle and provide insights for further research to improve disease management strategies and overall animal health in the dairy industry.

High diversity, novel genotypes, and vertical transmission of hemotropic Mycoplasma in micromammals

Hemotropic mycoplasmas (hemoplasmas) are emerging zoonotic pathogens. Micromammals have received little attention as hosts for hemoplasmas despite their ubiquitous presence, high population abundances, and close association with humans. A PCR protocol targeting a fragment of the 16 S rRNA gene and direct sequencing in blood samples of 189 adult specimens and 35 fetuses belonging to three species of Eulipotyphla (shrews) and seven species of Rodentia, captured in three ecologically diverse habitats in North-Eastern Spain (Steppe, High Mountain, Mediterranean) yielded and occurrence of 26%, including 36% of 39 shrews and 23% of 150 rodents. Sequencing revealed the presence of 14 nucleotide sequence types (ntST) among the 56 readable sequences. In general, each ntST was associated with a given host species, although in some cases, the same ntST was sequenced in different species (chiefly rodents). Most ntST were closely related to rodent and/or bat hemoplasmas, but one was identical with Mycoplasma haemocanis/haemofelis, and others can be considered novel genotypes. High sequence diversity was detected in rodents, whereas in the white-toothed shrew (Crocidura russula), 9/11 sequences from two distant areas were identical. Phylogenetic and network analyses classified our sequences in different clades including hemoplasmas of rodents, carnivores, bats, and humans. Twelve of the fetuses (34.2%) of 9/12 litters (75.0%) of shrews and rodents were hemoplasma-positive, indicating frequent vertical transmission. Our study contributes to expanding our knowledge about the distribution, diversity, and transmission of hemoplasmas.

Preliminary report of Mycoplasma Wenoynii and Candidatus Mycoplasma haemobos infection in Korean native cattle

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.

An Update of Bovine Hemoplasmas Based on Phylogenetic and Genomics Analysis

Mycoplasma wenyonii and ‘Candidatus Mycoplasma haemobos’ are bacteria that have been described as significant hemoplasmas that infect cattle worldwide. Currently, three bovine hemoplasma genomes are known. This work aimed to describe the main genomic characteristics and the evolutionary relationships between hemoplasmas, and provide a list of epitopes predicted by immunoinformatics as diagnostic candidates for bovine hemoplasmosis. Thus far, there is no vaccine to prevent this disease that economically impacts cattle production worldwide. Additionally, there is a lack of vaccines against bovine hemoplasmosis. In this work, we performed a genomic characterization of hemoplasmas, including two Mexican strains reported in bovines in the last few years. The generated information is a new scenario about the phylogeny of hemoplasmas. Also, we show genomic features among hemoplasmas that strengthen their characteristic genome plasticity of intracellular lifestyles. Finally, the elucidation of antigenic proteins in Mexican strains represents an opportunity to develop molecular detection methods and diagnoses.

Molecular detection of haemophilic pathogens reveals evidence of Candidatus Mycoplasma haemobos in dogs and parasitic ticks in central China

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.

Mo­lecular evidence and epidemiology of “Candidatus Mycoplasma haemobos” among cattle in Peninsular Malaysia using the 16S rRNA gene

Haemotropic Mycoplasma infection among cattle has not been seriously looked into, despite the fact it is associated with poor weight gain and depression. One thousand and forty-five blood samples from apparently healthy cattle from forty-three farms within the entire Peninsular Malaysia were exa­mined over a one-year period. Using polymerase chain reaction to amplify the 16S rRNA gene, the presence of “Candidatus Mycoplasma haemobos” as one of the haemotropic Mycoplasma species that affects cattle in the country was detected. Forty-seven percent of the sampled population was positive for “C. M. haemobos”, with the antigen present in all herds sampled. Breed of cattle, gender, age, production type, physiological status, herd size, management system, farm size, farm age, prophylactic treatment against blood parasites, presence of ticks, frequency of de-ticking, zone, closeness to forest, closeness to waste area, closeness to human settlement and closeness to body of water were all significantly associated (P<0.05) with the detection of “C. M. haemobos”. The findings from this study will be pivotal in government policy on this blood Mycoplasma infection, as the study happens to be the first comprehensive molecular survey of the microorganism in the country.

Detection of Mycoplasma wenyonii and "Candidatus Mycoplasma haemobos" from Japanese Black breeding cows in Kyushu and Okinawa region, southern part of Japan

This study aimed to elucidate the epidemiological status of hemoplasma infection and investigate the interaction between Theileria orientalis and hemoplasmas in Japanese Black breeding cows raised in the Kyushu and Okinawa regions. Blood samples were collected from 400 cows from 80 different farms in eight prefectures (five samples per farm and 10 farms per prefecture). Mycoplasma wenyonii (Mw), “Candidatus Mycoplasma haemobos” (CMh), and T. orientalis were examined by polymerase chain reaction (PCR) assay using whole blood samples. PCR results showed that 91.5% (366/400) of cows were positive for bovine hemoplasma: 40.3% were infected with Mw only, 9.5% with CMh only, and 41.8% with both species. T. orientalis was detected in 36% (144/400) of cows. The infection rate of T. orientalis was higher in the grazing group (P<0.001) than in the housed group, while the rate of CMh infection was higher (P<0.05) in the housed group than in the grazing group, suggesting that not only the tick but also other arthropod vectors may contribute to hemoplasma transmission. Although the cows with hemoplasma dual infection showed higher (P<0.05) white blood cell counts compared with hemoplasma-negative cows, there was no difference in hematologic parameters related to the anemia between the hemoplasma-positive and -negative animals. This may indicate that Japanese Black cattle could have resistance to the anemia caused by infection with hemoplasma.

Molecular Survey and Genetic Diversity of Hemoplasmas in Rodents from Chile

Even though hemotrophic mycoplasma (hemoplasma) infections are well documented in a wide variety of hosts worldwide, there is a gap in the knowledge aobut hemoplasmas in rodents. This study aimed to molecularly survey and investigate the genetic diversity of hemoplasmas in rodents from Chile. Synanthropic and wild rodents (n = 74) were captured in the southern province of Valdivia (Corral, Valdivia, Riñihue, and Reumén localities). Spleen samples were submitted to a conventional PCR for hemotrophic Mycoplasma spp. targeting the 16S rRNA gene (800 bp), followed by sequencing, phylogenetic, and genetic diversity analyses. The overall occurrence of hemotrophic mycoplasmas in rodents from Valdivia was 24.5% (18/74) [95% CI (14.5; 34.1)]. Hemoplasmas were detected in Mus musculus (1/4), Rattus norvegicus (1/16), Abrothrix longipilis (7/13), A. olivaceo (6/8), and Oligoryzomys longicaudatus (3/10). The nucleotide polymorphism analysis of the targeted 16S rRNA region showed low diversity, with two genotypes and a high identity to the variants detected in wild rodents from Brazil. Hemoplasmas are described for the first time in rodents from Chile with a moderate occurrence and low 16S rDNA genetic diversity within the sampled rodent population. The detected hemoplasma genotypes were specific to rodents and were not shared with other mammals.

Comparison of Light Microscopy and Polymerase Chain Reaction for the Detection of Haemoparasites in Cattle in Nigeria

PURPOSE

Haemoparasitic diseases are among the important factors that threaten cattle health and productivity especially in the sub-Saharan region. In Nigeria, their detection using sensitive molecular techniques is scanty. This study was designed to investigate and to reevaluate the repertoire of haemoparasites of cattle in Ibadan, Nigeria with a comparative evaluation of light microscopy (LM) and polymerase chain reaction (PCR) methods.

METHODS

Blood samples from 100 cattle slaughtered at Ibadan abattoirs were examined using LM and PCR techniques for haemoparasite detection. The PCR reactions using three primer sets targeting the 16S rRNA genes for Hemoplasma spp. and Anaplasma/Ehrlichia spp. and 18S rRNA genes of Babesia/Theleiria spp. were done. A few randomly selected amplicons from each set were sequenced and analysed.

RESULTS

A total infection rate of 34% by LM including Hemoplasma spp. (17%), Anaplasma spp. (16%), microfilaria (5%) and Trypanosoma spp. (12%) was recorded. While, 86% positivity was recorded with PCR amplification as follows: Hemoplasma spp. (64%), Babesia/Theleiria spp. (46%) and Anaplasma/Ehrlichia spp. (5%). Comparison of LM and PCR findings showed that no LM Anaplasma spp.-positive samples and 7 out of the 17 LM hemoplasma-positive cattle were confirmed by PCR. In addition, LM led to misdiagnosis of 46 Babesia/Theleiria spp.-positive samples. Amplicon sequencing and phylogenetic analysis of Babesia/Theileria spp.-positive samples revealed Theileria velifera and Theileria annulata. In the Anaplasma/Ehrlichia spp.-positive samples, only Anaplasma marginale was characterized. Mycoplasma wenyonii, "Candidatus Mycoplasma haemobos" and Pseudomonas fluorescens like were characterized among the hemoplasma-infected cattle.

CONCLUSIONS

The first report of "Candidatus Mycoplasma haemobos" and Pseudomonas fluorescens like in Nigerian cattle is herewith documented. The alarming LM misdiagnosis of haemoparasites during this study confirms its limitations as it fails to identify many parasites and emphasizes the need for inclusion of molecular techniques to improve their detection. The study also shows for the first time the high prevalence of haemotropic mycoplasma in Nigerian cattle via molecular diagnostic methods, thus indicating a strong need for the investigation of their zoonotic implications.

Occurrence and genetic diversity of hemoplasmas in beef cattle from the Brazilian Pantanal, an endemic area for bovine trypanosomiasis in South America

Hemotropic mycoplasmas (hemoplasmas) are Gram-negative bacteria that parasitize the erythrocyte surface of a wide variety of mammals. The present study aimed at investigating the occurrence of hemoplasmas in beef cattle in the Brazilian Pantanal, an area endemic for bovine trypanosomiasis in South America. Additionally, the objective of this study was to characterize molecularly the genotypes of the found hemoplasmas. For this purpose, blood and serum samples of 400 beef cattle were collected from five properties in Corumbá, Nhecolândia sub-region, Mato Grosso do Sul, in Midwest Brazil. Blood samples underwent DNA extraction and standard 16S rRNA gene-based PCR assays for hemoplasmas. The sequences obtained were submitted to phylogenetic inferences, distance analysis, and genotype diversity. The Indirect Enzyme-Linked Immunoabsorbent Assay (iELISA) indicated the presence of anti-Trypanosoma vivax IgG antibodies in 89.75% of the animals sampled, confirming the endemicity of said agent in the studied region. Among the 400 bovine blood samples tested, 2.25% (9/400) were positive for hemoplasmas in cPCR. The phylogenetic analysis of the obtained sequences confirmed the presence of 'Candidatus Mycoplasma haemobos' and Mycoplasma wenyonii DNA in 0.5% (2/400) and 1.75% (7/400) animals, respectively. Five genotypes of M. wenyonii and one of 'Candidatus M. haemobos' were detected among the sequenced amplicons. The present study showed low molecular occurrence of haemoplasmas in beef cattle sampled in the Brazilian Pantanal, an area endemic for bovine trypanosomiasis. Despite of the conservation of the 16S rRNA gene, there was considerable diversity of hemoplasma genotypes infecting the sampled beef cattle.

First detection of Mycoplasma wenyonii in France: Identification, evaluation of the clinical impact and development of a new specific detection assay

Mycoplasma wenyonii, a hemoplasma infecting cattle, was never detected in France. In 2014, evocative inclusions were observed in erythrocytes from cattle presenting milk drops, anemia, and edema in Brittany (France). A survey was then initiated to investigate the epidemiological situation and correlate mycoplasma detection with clinical signs. For this purpose, a new PCR assay targeting polC gene was designed. Comparative results with published PCR assays place this new one as more specific, allowing a one-step diagnosis without further sequencing. A total of 181 cows were included in this study and 4.97% (n = 9) were positive, resulting in the first molecular identification of M. wenyonii in France. All positive animals presented anemia, edema and milk drop. When selecting animals presenting evocative clinical signs, the prevalence of M. wenyonii in Brittany was estimated to 25.6%. Further studies are needed to evaluate the importance of the infection, the implication of arthropods and the existence of asymptomatic carriers.

Hemotrophic mycoplasma in Simmental cattle in Bavaria: prevalence, blood parameters, and transplacental transmission of 'Candidatus Mycoplasma haemobos' and Mycoplasma wenyonii

Background

The significance of hemotrophic mycoplasma in cattle remains unclear. Especially in Europe, their epidemiological parameters as well as pathophysiological influence on cows are lacking. The objectives of this study were: (1) to describe the prevalence of ‘Candidatus Mycoplasma haemobos’ (‘C. M. haemobos’) and Mycoplasma wenyonii (M. wenyonii) in Bavaria, Germany; (2) to evaluate their association with several blood parameters; (3) to explore the potential of vertical transmission in Simmental cattle; and (4) to evaluate the accuracy of acridine-orange-stained blood smears compared to real-time polymerase chain reaction (PCR) results to detect hemotrophic mycoplasma. A total of 410 ethylenediaminetetraacetic acid-blood samples from cows from 41 herds were evaluated by hematology, acridine-orange-stained blood smears, and real-time PCR. Additionally, blood samples were taken from dry cows of six dairy farms with positive test results for hemotrophic mycoplasma to investigate vertical transmission of infection.

Results

The period prevalence of both species was 60.24% (247/410), C. M. haemobos 56.59% (232/410), M. wenyonii 8.54% (35/410) and for coinfection 4.88% (20/410). Of the relevant blood parameters, only mean cell volume (MCV), mean cell hemoglobin (MCH), and white blood cell count (WBC) showed differences between the groups of infected and non-infected individuals. There were lower values of MCV (P < 0.01) and MCH (P < 0.01) and higher values of WBC (P < 0.05) in ‘C. M. haemobos’-infected cows. In contrast, co-infected individuals had only higher WBC (P < 0.05). In M. wenyonii-positive blood samples, MCH was significantly lower (P < 0.05). Vertical transmission of ‘C. M. haemobos’ was confirmed in two calves. The acridine-orange-method had a low sensitivity (37.39%), specificity (65.97%), positive predictive value (63.70%) and negative predictive value (39.75%) compared to PCR.

Conclusions

‘Candidatus Mycoplasma haemobos’ was more prevalent than M. wenyonii in Bavarian Simmental cattle, but infection had little impact on evaluated blood parameters. Vertical transmission of the infection was rare. Real-time PCR is the preferred diagnostic method compared to the acridine-orange-method.

Haemoplasmas in wild rodents: Routes of transmission and infection dynamics

The way that some parasites and pathogens persist in the hostile environment of their host for long periods remains to be resolved. Here, longitudinal field surveys were combined with laboratory experiments to investigate the routes of transmission and infection dynamics of such a pathogen-a wild rodent haemotropic bacterium, specifically a Mycoplasma haemomuris-like bacterium. Fleaborne transmission, direct rodent-to-rodent transmission and vertical transmission from fleas or rodents to their offspring were experimentally quantified, and indications were found that the main route of bacterial transmission is direct, although its rate of successful transmission is low (~20%). The bacterium's temporal dynamics was then compared in the field to that observed under a controlled infection experiment in field-infected and laboratory-infected rodents, and indications were found, under all conditions, that the bacterium reached its peak infection level after 25-45 days and then decreased to low bacterial loads, which persist for the rodent's lifetime. These findings suggest that the bacterium relies on persistency with low bacterial loads for long-term coexistence with its rodent host, having both conceptual and applied implications.

Quantitative analysis of Mycoplasma wenyonii and 'Candidatus Mycoplasma haemobos" infections in cattle using novel gapN-based realtime PCR assays

Hemotrophic mycoplasmas (HMs) are associated with anemia and other disease complexes in a wide range of livestock and wild animals. Two bovine HM species have been identified to date, i.e. Mycoplasma wenyonii and 'Candidatus Mycoplasma haemobos'. The study aim was to develop quantitative real-time PCR assays (qPCRs) to detect and quantify M. wenyonii and 'C. M. haemobos' and to apply these assays to DNA samples extracted from bovine blood collected in Germany (n = 220) from 22 herds. The qPCR assays specific for M. wenyonii and 'C. M. haemobos' were designed using the gapN of the respective hemoplasma species as gene target which encodes the NADP-dependent glyceraldehyde 3-phosphate dehydrogenases (GAPN). The sensitivity of both assays was 10 genome equivalents per reaction, corresponding to 2500 genome equivalents per ml blood. No cross-reactivity with non-target bovine HMs. and other bovine pathogens was observed. Bovine HM DNA was detected in 137 samples (62.27%) with 118 samples (53.64%) being positive for 'C.M. haemobos' and 19 samples (8.64%) being positive for M. wenyonii. Thereof, 11 animals (5.00%) were co-infected with both bovine HM species. The found herd prevalence for `C. M. haemobos` was 100.00%, and for M. wenyonii 36.36% with mean bacterial loads of 3.7 × 10⁷ `C. M. haemobos`/mL blood and of 4.29 × 10⁵M. wenyonii/mL blood respectively. Clinical and economic relevance of bovine HM species should be goal of future studies for which the novel gapN qPCR assays can serve as a valuable diagnostic tool.

Novel hemotropic mycoplasmas are widespread and genetically diverse in vampire bats

Bats (Order: Chiroptera) have been widely studied as reservoir hosts for viruses of concern for human and animal health. However, whether bats are equally competent hosts of non-viral pathogens such as bacteria remains an important open question. Here, we surveyed blood and saliva samples of vampire bats from Peru and Belize for hemotropic Mycoplasma spp. (hemoplasmas), bacteria that can cause inapparent infection or anemia in hosts. 16S rRNA gene amplification of blood showed 67% (150/223) of common vampire bats (Desmodus rotundus) were infected by hemoplasmas. Sequencing of the 16S rRNA gene amplicons revealed three novel genotypes that were phylogenetically related but not identical to hemoplasmas described from other (non-vampire) bat species, rodents, humans, and non-human primates. Hemoplasma prevalence in vampire bats was highest in non-reproductive and young individuals, did not differ by country, and was relatively stable over time (i.e., endemic). Metagenomics from pooled D. rotundus saliva from Peru detected non-hemotropic Mycoplasma species and hemoplasma genotypes phylogenetically similar to those identified in blood, providing indirect evidence for potential direct transmission of hemoplasmas through biting or social contacts. This study demonstrates vampire bats host several novel hemoplasmas and sheds light on risk factors for infection and basic transmission routes. Given the high frequency of direct contacts that arise when vampire bats feed on humans, domestic animals, and wildlife, the potential of these bacteria to be transmitted between species should be investigated in future work.

Molecular characterization of hemotropic mycoplasmas (Mycoplasma ovis and 'Candidatus Mycoplasma haemovis') in sheep and goats in China

BACKGROUND

Hemotropic mycoplasmas (hemoplasmas) are emerging zoonotic pathogens with a worldwide distribution that can cause mild to severe hemolytic anemia, icterus, ill-thrift, infertility, and poor weight gain. However, understanding of the molecular epidemiology of hemoplasmas (Mycoplasma ovis and 'Candidatus Mycoplasma haemovis') is limited in sheep and goats, and the hemoplasma strain/species/variant 'Candidatus M. haemovis' was poorly studied throughout the world and had never been detected in China until now. Thus, the aim of the present study was to determine the molecular prevalence of hemoplasmas, including M. ovis and 'Candidatus M. haemovis' in sheep and goats from seven provinces and one autonomous region of China.

METHODS

A total of 1364 blood samples were collected from sheep and goats in seven provinces and one autonomous region of China. All blood samples were tested for hemoplasmas (M. ovis and 'Candidatus M. haemovis') by nested PCR amplification based on 16S rRNA gene. Positive specimens underwent nucleotide sequencing and phylogenetic analysis.

RESULTS

Overall, 610 specimens (44.7%, 610/1364) were shown to be hemoplasmas (M. ovis and 'Candidatus M. haemovis') -positive by nested PCR amplification based on 16S rRNA gene. The prevalence in goats was 44.1% (379/860), and 45.8% (231/504) in sheep, while that in grazing small ruminants was 54.4% (396/728) and 33.6% (214/636) in house feeding small ruminants. Sequencing of the nearly complete 16S rRNA gene was successful for the 103 randomly selected positive specimens from different farms in different sampling sites of China. Among them, analysis of the 16S rRNA gene sequences identified M. ovis (n = 56) and 'Candidatus M. haemovis' (n = 47). Two (KU983740 and KU983746) of the four novel genotypes obtained in this study were closely related to M. ovis, while the other two genotypes (KU983748 and KU983749) had high identity with 'Candidatus M. haemovis'. Remarkably, the genotype (KU983740) of M. ovis in sheep and goats in this study fell in a clade with two human hemoplasmas from USA (KF313922 and GU230144) and shared 99.8%-99.9% with them.

CONCLUSIONS

In this study, 'Candidatus M. haemovis' was first detected in Chinese sheep and goats and hemoplasmas (M. ovis and 'Candidatus M. haemovis') are highly prevalent, and widely distributed in China.

Risk factors of different hemoplasma species infections in cats

Background

Hemoplasma species (spp.) commonly cause infections in cats worldwide. However, data on risk factors for infections are limited. The aim of this study was to determine the prevalence of hemoplasma spp. infections in cats in Southern Germany and to assess risk factors associated with infection.

Results

DNA was extracted from blood samples of 479 cats presented to different veterinary hospitals for various reasons. DNA of feline hemoplasmas was amplified by use of a previously reported PCR assay. Direct sequencing was used to confirm all purified amplicons and compared to hemoplasma sequences reported in GenBank. Results were evaluated in relation to the age, sex, housing conditions, feline leukemia virus (FeLV) and feline immunodeficiency virus (FIV) status of the cats.

The overall hemoplasma prevalence rate was 9.4% (45/479; 95% CI: 7.08–12.36). ‘Candidatus Mycoplasma (M.) haemominutum’ (Mhm) DNA was amplified from 42 samples, M. haemofelis from 2, and M. haemocanis from 1 sample. There was a significantly higher risk of hemoplasma infection in cats from multi-cat households, in outdoor cats, as well as in cats with FIVinfection and in cats with abortive FeLV infection, but not in cats with progressive or regressive FeLV infection.

Conclusions

Mhm infection is common in cats in Southern Germany. Higher prevalence in multi-cat households and associations with FeLV infection likely reflect the potential for direct transmission amongst cats. Outdoor access, male gender, and FIV infection are additional risk factors that might relate to aggressive interactions and exposure to vectors.

Hemotropic mycoplasmas in little brown bats (Myotis lucifugus)

Background

Hemotropic mycoplasmas are epicellular erythrocytic bacteria that can cause infectious anemia in some mammalian species. Worldwide, hemotropic mycoplasmas are emerging or re-emerging zoonotic pathogens potentially causing serious and significant health problems in wildlife. The objective of this study was to determine the molecular prevalence of hemotropic Mycoplasma species in little brown bats (Myotis lucifugus) with and without Pseudogymnoascus (Geomyces) destrucans, the causative agent of white nose syndrome (WNS) that causes significant mortality events in bats.

Methods

In order to establish the prevalence of hemotropic Mycoplasma species in a population of 68 little brown bats (Myotis lucifugus) with (n = 53) and without (n = 15) white-nose syndrome (WNS), PCR was performed targeting the 16S rRNA gene.

Results

The overall prevalence of hemotropic Mycoplasmas in bats was 47%, with similar (p = 0.5725) prevalence between bats with WNS (49%) and without WNS (40%). 16S rDNA sequence analysis (~1,200 bp) supports the presence of a novel hemotropic Mycoplasma species with 91.75% sequence homology with Mycoplasma haemomuris. No differences were found in gene sequences generated from WNS and non-WNS animals.

Conclusions

Gene sequences generated from WNS and non-WNS animals suggest that little brown bats could serve as a natural reservoir for this potentially novel Mycoplasma species. Currently, there is minimal information about the prevalence, host-specificity, or the route of transmission of hemotropic Mycoplasma spp. among bats. Finally, the potential role of hemotropic Mycoplasma spp. as co-factors in the development of disease manifestations in bats, including WNS in Myotis lucifugus, remains to be elucidated.

Novel hemotropic Mycoplasma species in white-tailed deer (Odocoileus virginianus)

Globally, hemotropic Mycoplasma spp. are emerging or re-emerging zoonotic pathogens that affect livestock, wildlife, companion animals, and humans, potentially causing serious and economically important disease problems. Little is known about hemotropic Mycoplasma spp. prevalence, host-specificity, or route of transmission in most species, including wildlife. DNA amplification by PCR targeting the 16SrRNA and the RNaseP genes was used to establish the presence and prevalence of hemotropic Mycoplasma spp. in a white-tailed deer (O. virginianus) population in eastern North Carolina. Sixty-five deer (89%) tested positive for hemotropic Mycoplasma spp. where sequence analysis of the 16SsRNA and the RNaseP genes indicated the presence of at least three distinct species. This study represents the first detection of three distinct hemotropic Mycoplasma species in white-tailed deer and the first report of two novel hemotropic Mycoplasma species.

Complete genome sequence of Mycoplasma wenyonii strain Massachusetts

Mycoplasma wenyonii is a hemotrophic mycoplasma that causes acute and chronic infections in cattle. Here, we announce the first complete genome sequence of this organism. The genome is a single circular chromosome with 650,228 bp and G+C% of 33.9. Analyses of M. wenyonii genome will provide insights into its biology.

Prevalence and risk factor analysis of bovine hemoplasma infection by direct PCR in Eastern Hokkaido, Japan

The prevalence and risk factors of 2 bovine hemoplasma species-Mycoplasma wenyonii (Mw) and "Candidatus Mycoplasma haemobos" (CMh)-were examined by direct PCR using whole blood samples collected from 343 cattle in Eastern Hokkaido, Japan. The sensitivity of the direct PCR assay was 10-fold higher than the standard PCR assay, detecting 5 copies of bovine hemoplasma DNA per reaction. An epidemiological survey of sampling location, living conditions, age and bovine leukemia virus antibody was performed to assess infection risk factors. The prevalence rates were 38.5% for Mw and 39.1% for CMh, respectively, with an overall prevalence rate of 64.7% for all bovine hemoplasma infections. Significant differences were found in sampling location, living conditions and age. Compared with pastured cattle, farmed cattle were significantly more susceptible to infection with total hemoplasma species (P<0.001), and were particularly susceptible to CMh (P<0.001). Cattle that were 1-3 years of age were more susceptible to infection with hemoplasma compared with other age groups. Bovine leukemia virus infection status was not significantly associated with hemoplasma infections. Blood examination revealed significantly lower RBC, Hb, and PCV levels, and a higher MCV in infected cattle than in noninfected cattle.