Investigating the contamination rate and antibiotic resistance of Salmonellagallinarum in laying poultry herds of East Azarbaijan province in ۲۰۲۱

Background and Objective: Some species of the genus Salmonella, including Salmonella gallinarum,are the cause of many chronic and acute diseases in industrial and ornamental poultry. Diseases caused bythis bacterium can cause complications such as production drop in the flock, mortality, reduced fertility,and reduced growth among birds. Therefore, every year money and expenses are spent on the control andtreatment of diseases caused by Salmonella gallinarum. Due to the widespread use of antibiotics intreatment, the incidence of drug resistance and gene mutations among bacteria has increased. Therefore,considering the importance of this bacterium in poultry contamination and its effect on human nutrition,the purpose of this research is to investigate and determine the pattern of antibiotic resistance inSalmonella gallinarum isolated from egg-laying poultry.Methods: In this study, first, during a period of approximately three months in ۱۴۰۰, reference layinghens were collected from different farms of East Azarbaijan province, which had disease symptoms.Then, samples were taken from ۱۴ herds suspected of having signs of involvement with Salmonellagallinarum. In order to identify the mentioned bacteria, culture in differential media and biochemical testswere used, after determining the serotype, an antibiogram test in Mueller Hinton agar culture mediumusing imipenem, meropenem, cefepime, ceftazidime discs. Ceftizoxim, ciprofloxacin, amikacin,cefazolin, enrofloxacin, fosfomycin, danofloxacin, tetracycline, doxycycline, sultrim, erythromycin, andamoxicillin were performed.Results: The results show that the positive samples for the presence of Salmonella gallinarum in the egglayingpoultry of East Azarbaijan province, all the suspected samples were clinically positive. Also,during the antibiogram examination, the resistance of the studied samples to ceftazidime ۶۰%, cefepime۵۰%, cefazolin ۴۴%, amikacin ۴۰%, doxycycline ۳۱%, ciprofloxacin ۳۰%, enrofloxacin ۳۰%,erythromycin ۲۷% respectively. , imipenem ۱۵%, ceftizoxime ۱۰%, meropenem ۷%, tetracycline ۷%,danofloxacin ۲%, fosfomycin ۲%, sultrim ۱%, amoxicillin ۱% were reported. Therefore, the results of theantibiogram indicated the resistance of Salmonella gallinarum isolated from the laying hens to someantibiotics.Conclusion: According to the drug resistance obtained in this research, it can be concluded that there is arisk of increasing the antibiotic resistance of Salmonella gallinarum among the poultryflocks of East Azarbaijan province. Therefore, in order to prevent contamination and correct treatment,monitoring and appropriate solutions by the country's health officials are very important.

کلیدواژه ها:

Antibiotic resistance ، East Azerbaijan ، Salmonella gallinarum