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Mycoplasma hyopharyngis is a commensal bacterium in the upper respiratory tract of swine. As it is recognized to be apathogenic, examinations regarding this species are scarce, compared to other swine mycoplasmas. However, in a few cases, M. hyopharyngis was detected in lesions of different organs. This report presents a case study in which M. hyopharyngis (along with other bacteria) was isolated from the joint of a pig showing lameness. A Hungarian farm was repopulated with 250 gilts and 1,700 finishers after undergoing a complete depopulation and disinfection. Two days later, cases of diarrhoea and septicaemia caused by Salmonella enterica serovar typhimurium were seen in the finishers. At the same time, following the first farrowing, swollen joints were observed in 21–25 days old piglets. Joint samples were collected, and isolation of Mycoplasma sp. and other bacteria was attempted. Analysis of the joint samples revealed the presence of Staphylococcus haemolyticus, Staphylococcus hyicus, Aerococcus viridans, Trueperella pyogenes, Streptococcus agalactiae and M. hyopharyngis. This is the second isolation of M. hyopharyngis from joints, which highlights the necessity of a better understanding the biology of this often-overlooked species, and its role in the progress of arthritis or other lesions. [ABSTRACT FROM AUTHOR]

The aim of the present study was to monitor the dynamics and to measure the safety and efficacy of a live, attenuated, thermosensitive Mycoplasma anserisalpingitidis vaccine candidate, namely MA271, in geese breeder flocks under field conditions. Two rearing flocks were vaccinated with MA271 at 4 weeks of age and boosted at 24 weeks of age by cloaca inoculation (1 ml) and eye-dropping (60 µl). The geese then were transported to multi-aged breeding farms. Two breeding flocks served as controls. Colonization of the cloaca by MA271 showed 75% maximum prevalence between 4 and 6 weeks after the first vaccination. Then the prevalence decreased to 25% until the cooler, humid fall months which coincided with the booster vaccination. Boosting raised cloacal colonization to 100%. No clinical signs were observed in the vaccinated birds. After transportation to five multi-aged breeding farms, the wild-type strain appeared as well as MA271 in three flocks. In one flock, the wild-type strain completely displaced MA271, while in one flock only MA271 was detected. Only wild-type strains were detected in the control flocks; however, due to an HPAI outbreak, both flocks were exterminated before the end of the study. Based on the available data, the median percentage of infertile eggs was 3.7-5.1% in the MA271 vaccinated flocks, and 7.7% in the non-vaccinated flock. In conclusion, MA271 can colonize the cloaca of geese under field conditions. MA271 proved to be safe and presumably protects against M. anserisalpingitidis-induced reproduction losses. [ABSTRACT FROM AUTHOR]

Introduction: Mycoplasma anserisalpingitidis is one of the most important waterfowl-pathogenic mycoplasmas. Due to inadequate antibiotic treatment, many strains with high minimal inhibitory concentration (MIC) values for multiple drugs have been isolated lately. Decreased antibiotic susceptibility in several Mycoplasma species are known to be associated with mutations in topoisomerase and ribosomal genes, but other strategies such as active efflux pump mechanisms were also described. The scope of this study was the phenotypic and genetic characterization of the active efflux mechanism in M. anserisalpingitidis Methods: We measured the MIC values in the presence and absence of different efflux pump inhibitors (EPIs), such as carbonyl cyanide m-chlorophenylhydrazine (CCCP), orthovanadate (OV), and reserpine (RSP). Moreover, bioinformatic tools were utilized to detect putative regulatory sequences of membrane transport proteins coding genes, while comparative genome analysis was performed to reveal potential markers of antibiotic resistance. Results: Out of the three examined EPIs, CCCP decreased the MICs at least twofold below the original MICs (in 23 cases out of 36 strains). In the presence of OV or RSP, MIC value differences could be seen only if modified dilution series (10% decrease steps were used instead of two-fold dilutions) were applied (in 24/36 cases with OV and 9/36 with RSP). During comparative genome analysis, nonsynonymous single nucleotide polymorphisms (nsSNPs) were identified in genes encoding ABC membrane transport proteins, which were displayed in higher percentages in M. anserisalpingitidis strains with increased MICs. In terms of other genes, a nsSNP was identified in DNA gyrase subunit A (gyrA) gene which can be related to decreased susceptibility to enrofloxacin. The present study is the first to highlight the importance of efflux pump mechanisms in M. anserisalpingitidis. Discussion: Considering the observed effects of the EPI CCCP against this bacterium, it can be assumed, that the use of EPIs would increase the efficiency of targeted antibiotic therapy in the future control of this pathogen. However, further research is required to obtain a more comprehensive understanding of efflux pump mechanism in this bacterium. [ABSTRACT FROM AUTHOR]