Search Results (8)

Microbiomes have become an increasingly important field of study in the past decade, with data supporting microbial roles in disease control, metabolic efficiency, and more. Microbial DNA is detectable outside the digestive tract, including in blood. Bloodborne pathogens such as hemotrophic Mycoplasma are endemic in cattle. Hemoplasmas are associated with reduced male fertility and decreased milk production in dairy cattle, but their impact on beef cattle remains unclear. Strain variability, such as between the Massachusetts and INFAP01 strains of Mycoplasma wenyonii, may complicate detection. Coinfection with multiple species likely contributes to disease progression from latent to acute infection. To assess microbial DNA in blood and quantify erythrocytic M. wenyonii, blood was collected from 120 beef cattle in Erath County, Texas: 61 cows, 55 calves, and 4 bulls. DNA was extracted and used to prepare 16S rRNA V4 libraries and perform PCR. After rarefaction, ASVs were analyzed and separated into four groups: adult females (n = 61), adult males (n = 4), juvenile males (n = 27), and juvenile females (n = 28). Statistical analysis revealed differences in Actinobacteria by sex (p < 0.001) and higher Bartonella and Mycoplasma abundances in adults (p < 0.001). PCR revealed that M. wenyonii infection was more frequent in adult females (p = 0.006), suggesting age-related variation in infection. Full article

The emerging field of study of blood microbiota reveals the presence of bacteria in the blood of healthy animals. In endangered species such as the American bison (Bison bison), the analysis of this microbiota is crucial for conservation, as changes in these communities or the development of pathogens may affect their health and compromise herd viability. Here, we analyzed and compared the bacterial blood microbiota of healthy adult and juvenile bison in Mexico (Janos, Chihuahua), identifying those bacterial taxa with potential pathogenicity for these individuals. Blood samples were collected from 12 juvenile and 12 adult bison. The V3–V4 region of the 16S rRNA gene was amplified, and next-generation sequencing was subsequently performed on the Illumina NovaSeq platform. The bacterial taxa observed in the blood of these individuals (Firmicutes, Proteobacteria, Bacteroidota, Actinobacteria, Fusobacteriaceae, Lachnospiraceae, Oscillospiraceae, and Ruminococcaceae) have been previously reported to be abundant in the rumen and feces of bison. The most notable difference was observed for Mycoplasma wenyonii, which was significantly enriched in juveniles compared with adults. New sequencing technologies can be practically applied to improve the management and conservation of vulnerable species such as the American bison. Full article

This study aimed to describe the bacterial composition of the surgical site during elective caesarean sections (CSs) using the 16Sr DNA amplicon sequencing performed in parallel to bacterial culture. The study involved 13 Belgian blue cows of a previous dataset of 76 animals. Bacteriology was performed on swabs sampled from visceral and parietal peritoneum during the CS. Amplicon sequencing was performed in six samples chosen randomly among the swabs positive for bacteriology and seven among the culture-negative swabs. A total of 2542 bacterial operational taxonomic units belonging to 567 genera were identified. The most often identified genus and species were Mycoplasma (44%) and Mycoplasma wenyonii (36%), respectively. Results showed no difference in microbiota composition between the culture-positive and -negative samples. However, a difference was observed between the bacteriology and amplicon sequencing results. Indeed, seven out of nine cultured strains were not identified by amplicon sequencing in the samples in which they were cultured. In contrast to bacteriology, amplicon sequencing unveiled the presence of bacterial DNA in all elective CSs. The most identified DNA is most likely derived from the haematogenous spread of bacteria to the surgical site. Furthermore, the cultured bacteria were not the dominant species in the sample from which they were cultured. Full article

An outbreak of disease in a Swedish beef cattle herd initiated an in-depth study to investigate the presence of bacteria and viruses in the blood of clinically healthy (n = 10) and clinically diseased cattle (n = 20) using whole-genome shotgun sequencing (WGSS). The occurrence of infectious agents was also investigated in ticks found attached to healthy cattle (n = 61) and wild deer (n = 23), and in spleen samples from wild deer (n = 30) and wild boars (n = 10). Moreover, blood samples from 84 clinically healthy young stock were analysed for antibodies against Anaplasma phagocytophilum and Babesia divergens. The WGSS revealed the presence of at least three distinct Mycoplasma variants that were most closely related to Mycoplasma wenyonii. Two of these were very similar to a divergent M. wenyonii variant previously only detected in Mexico. These variants tended to be more common in the diseased cattle than in the healthy cattle but were not detected in the ticks or wild animals. The DNA of A. phagocytophilum was detected in similar proportions in diseased (33%) and healthy (40%) cattle, while 70% of the deer, 8% of ticks collected from the cattle and 19% of the ticks collected from deer were positive. Almost all the isolates from the cattle, deer and ticks belonged to Ecotype 1. Based on sequencing of the groEL-gene, most isolates of A. phagocytophilum from cattle were similar and belonged to a different cluster than the isolates from wild deer. Antibodies against A. phagocytophilum were detected in all the analysed samples. In conclusion, uncommon variants of Mycoplasma were detected, probably associated with the disease outbreak in combination with immune suppression due to granulocytic anaplasmosis. Moreover, A. phagocytophilum was found to be circulating within this cattle population, while circulation between cattle and deer occurred infrequently. Full article

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. Full article

Fleas are considered as hosts for a wide range of pathogens that cause emerging and re-emerging zoonotic diseases worldwide. Data on fleas and flea-borne pathogens (FBPs) in the international literature are limited in Vietnam. This study aimed to investigate the species of fleas and the presence of pathogens of interest in fleas in northern Vietnam using PCR and sequence analysis. Out of 200 dogs enrolled in this study, 20% were infested by the flea species Ctenocephalides felis felis. In total, 62 fleas (35 females and 27 males) collected from domestic dogs were molecularly screened for the detection of pathogens. Out of the screened fleas, 39 were positive for Rickettsia felis (62.9%), 9 for Candidatus Mycoplasma hemobos (14.52%), and 6 for Mycoplasma wenyonii (9.68%). This study shows the first molecular detection of the above-mentioned pathogens in fleas collected from the studied areas and the potential risk of infection with examined FBPs in northern Vietnam. Full article

Arthropod-borne hemoparasites represent a serious health problem in livestock, causing significant production losses. Currently, the evidence of Anaplasma spp., Theileria spp., Babesia spp., and hemotropic Mycoplasma spp. in Algeria remains limited to a few scattered geographical regions. In this work, our objectives were to study the prevalence of these vector-borne pathogens and to search other agents not yet described in Algeria as well as the identification of statistical associations with various risk factors in cattle in the northeast of Algeria. Among the 205 cattle blood samples tested by PCR analysis, 42.4% positive results were obtained for at least one pathogen. The overall rates of Anaplasma spp., Theileria/Babesia spp., and Mycoplasma spp. in the cattle sampled were respectively 30.7%, 18.5%, and 2.9%; co-infections with multiple species was also detected. Anaplasma spp. and Theileria/Babesia spp. were detected at a higher rate in cattle under 3 years old, according to univariate analysis. Anaplasma spp. DNA was detected more frequently in our sample in cattle living in semi extensive farming. Our study provides additional data about Anaplasma spp., Theileria/Babesia spp. and reveals for the first time that Mycoplasma wenyonii and ‘Candidatus Mycoplasma hemobos are present in cattle in Northeast Algeria. Full article

Hemoplasmas (hemotropic mycoplasmas) are small pleomorphic bacteria that parasitize the surface of red blood cells of several mammalian species including cattle, goats, and humans, causing infectious anemia. However, studies on hemoplasmas have been neglected and to date, there are no studies on bovine and caprine hemoplasmas in Uganda or the entire East African region. In this study, a polymerase chain reaction (PCR) assay targeting the 16S rRNA gene was used to investigate the presence of hemoplasma in 409 samples (cattle = 208; goats = 201) collected from Kasese district, western Uganda. Results showed that 32.2% (67/208) of cattle samples and 43.8% (88/201) of goat samples were positive for hemoplasmas. Sequencing analysis identified Candidatus Mycoplasma haemobos and Mycoplasma wenyonii in cattle, while Candidatus Mycoplasma erythrocervae and Mycoplasma ovis were identified in goats. Statistical analysis showed that goats were at a higher risk of infection with hemoplasmas compared with cattle. To the best of our knowledge, this is the first molecular evidence of hemoplasmas in bovine and caprine animals in Uganda and the entire east African region. Full article