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ABSTRACT A major risk to the poultry industry is antimicrobial resistance (AMR), specifically with regard to Mycoplasma gallisepticum (MG) infections. The sensitivity patterns of 100 MG isolates to biocides and antibiotics were examined in this study to clarify the interactions between antimicrobial agents and resistance mechanisms. The antimicrobial activity against MG was assessed using broth microdilution, and the results are shown as the minimum inhibitory concentration (MIC) for each strain, the MIC distribution (range), the MIC50, and/or the MIC90. The statistical associations between the MICs of the antibiotics and biocides were investigated using regression model analysis and correlation coefficients. The absence of a cell wall in MG inherently confers resistance to beta‐lactams, thereby necessitating the utilization of enrofloxacin, difloxacin, flumequine, oxytetracycline, chlortetracycline, doxycycline, tylosin, tilmicosin, tylvalosin, erythromycin, spiramycin, tiamulin, lincomycin, spectinomycin and dihydrostreptomycin. These antibiotics exhibited MIC50 values of 0.5, 0.5, 0.12, 0.062, 0.12, 0.031, 0.016, 0.016, 0.062, 16, 1, 0.008, 2, 0.5 and 32, respectively. In addition to antibiotics, disinfectants have garnered attention for their contribution to the development of AMR in MG. Notably, formalin, phenol, NADES, Halamid, Virkon‐S, MicroSet and SteriSet exhibited MIC50 values of 125, 500, 31.25, 15.63, 15.63, 7.81 and 62.5, respectively. Significant positive correlations and direct associations were identified between various biocides and the development of antibiotic resistance, with coefficients ranging from 0.098 to 1.176. This research highlights the intricate nature of resistance profiles in MG and underscores the necessity for a thorough understanding of antimicrobial interactions. This finding emphasizes the importance of managing emerging AMR stemming from disinfectant misuse in the poultry farms to prevent additional constraints on antibiotic treatment options.

ABSTRACT: The incidence of chronic respiratory disease (CRD) due to Mycoplasma gallisepticum (MG) contamination in hatching eggs poses a serious threat to poultry health and hatchability. Implementing effective sanitization methods while safeguarding the hatching potential of embryos is crucial. This study aimed to explore novel techniques for sanitizing hatching-fertile eggs to prevent and manage MG-associated CRD. The primary objective was to assess the efficacy of acidic electrochemically stimulated water (ECS), focusing on MG disinfection. Additionally, the study investigated 2 application methods, 1) electrostatic disinfection (ED) and 2) cold fog (CF) disinfection, to evaluate their bactericidal effects against MG-contaminated eggs. Deliberately infected MG strains were used for the experimental design, which compared the disinfection efficacy of ECS with its acidic properties. The comparison involved ED, which applies an electrostatic charge to water particles, and CF disinfection, a cold mist technique. Both methods aimed to target MG without compromising egg-hatching potential. The results indicated a significant (p < 0.05) reduction in colony-forming units per milliliter (CFU/mL). However, both application methods demonstrated distinct bactericidal effects. Eggs treated with electrostatic disinfection showed a significant (p < 0.001) reduction in embryonic mortality during incubation (10%) compared to control untreated eggs (18%). Similarly, the CF method exhibited a significant (p < 0.001) decrease in embryonic mortality (13%). The ECS potential in reducing embryonic mortality within the pH range of 2.5 to 6.5 was noted. Both the ED and CF methods show promise for preventing MG-induced hatchery infection while maintaining egg-hatching potential. This study presents innovative techniques to control MG in hatching eggs, contributing to improved poultry health and reduced CRD incidence.