Detection and antibiotic resistance of Mycoplasma gallisepticum and Mycoplasma synoviae among chicken flocks in Egypt

Abstract

Background and Aim: Mycoplasma gallisepticum (MG) and Mycoplasma synoviae (MS) are the most significant pathogens of avian mycoplasmosis. This study aimed to isolate and identify MG and MS from chickens and detect the various virulence genes in the isolates. Moreover, the efficacies of different antibiotics were tested to identify suitable treatment regimens. Materials and Methods: We isolated MG and MS from 487 chicken samples of different ages located in different Governorates in Egypt using conventional isolation methods. The isolates were characterized by polymerase chain reaction (PCR) and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and then tested for antibiotic sensitivity by the minimum inhibitory concentration (MIC) method. Results: The prevalence of MG among the isolates was 9.85%, with the highest percentage isolated from air sacs, while the prevalence of MS among the isolates was 1.6%. Moreover, the highest levels of the prevalence of both MG and MS were during the winter and autumn sampling, while the lowest levels were in the summer and spring. Following the 16S rRNA-based detection of Mycoplasma isolates, 14 MG and 5 MS isolates were identified by different PCR-based detection methods for various virulence genes. Nine MG isolates contain the mgc2 gene, six MG isolates contain the gapA gene, and three MS isolates contain the vlhA gene. We validated a duplex PCR method for the simultaneous identification of MG and MS, based on 100% of the MG and MS isolates generating common bands at 55 and 17 kDa, respectively. The MIC method identified tiamulin and spiramycin as the antibiotics of choice for the treatment of MG and MS infections, respectively. Conclusion: For more precise diagnosis of Mycoplasma infections in chicken flocks, conventional isolation methods must be confirmed by PCR. SDS-PAGE analysis helps in epidemiological studies and vaccine preparation. The MIC method can be used to help develop therapies to control avian mycoplasmosis infections.

Mycoplasma gallisepticum: a devastating organism for the poultry industry in Egypt

“…The incidence profiles of the study, as mentioned in the results, is closely nearly to the conclusion of Bharathi et al. (2018) , Erfan and Marouf (2019) , Emam et al. (2020) , Marouf et al.…”

“…From our results, the highest isolation percentage was 83% from infraorbital sinus aspirates, 79.4% from lung, 72% from air sacs, 67.4% from tracheal bifurcation, 40% from litter samples and 29.4% from tracheal swabs. Also, Mohamed (1997) , Reda and El-Samie (2012) , Emam et al. (2020) showed that the highest isolation percentage was from air sacs as 15.7, 23.3, and 21.5%, respectively.…”

“…The conventional, traditional methods for MG isolation and identification are laborious, time-consuming, less sensitive, and fail to detect Mycoplasma species from treated birds ( Emam et al., 2020 ). Meanwhile, the PCR technique is a quick, sensitive, and accurate method for detecting MG from suspected cases ( Gondal et al., 2015 ).…”

Pharmacokinetic/Pharmacodynamic Modeling of Spiramycin against Mycoplasma synoviae in Chickens

“…In the present study, the PK/PD findings demonstrated that the AUC 24h /MIC had the best correlation with the anti-mycoplasmal activity (correlation coefficient (R 2 ) = 0.9628). In accordance with that of Emam et al [ 55 ], the MIC of spiramycin against M. synoviae strain (MS WVU-1853) was estimated to be 0.0625 µg/mL. On the basis of this MIC, the obtained AUC 24h /MIC for mycoplasmacidal activity (185 h), the evaluated unbound portion of spiramycin in chicken plasma (65.4%), and the oral bioavailability (77.1%), the appropriate daily dosage of spiramycin needed to achieve a mycoplasmacidal effect (2 log 10 decline in the Mycoplasma count) against M. synoviae in chickens was calculated to be 15.6 mg/kg/day.…”

Molecular detection of Mycoplasma gallisepticum in different poultry breeds of Abbottabad and Rawalpindi, Pakistan

“…For in depth study of M. gallisepticum in a specific region to understand the epidemiological niche, transmission of diseases and finding of new track of outbreaks, there is need to adopt a most reliable technique for differentiation the specie in more detail (Loolmani et al, 2014). The mgc2 gene targeted in this study is most specific, and sensitive and can be used as reference only for molecular based identification of M. gallisepticum (Youni et al, 2018;Emam et al, 2020). The particle sequencing and analysis of mgc2 gene showed a 100 percent similarity of local isolates from this study with isolated reported from India.…”