Antibiotic Resistance Patterns of Salmonella enterica Serovar Enteritidis Strains Isolated from Broiler Chickens
Open Access
- Author:
- Linder, Jessica Ellen
- Area of Honors:
- Veterinary and Biomedical Sciences
- Degree:
- Bachelor of Science
- Document Type:
- Thesis
- Thesis Supervisors:
- Dr. Lester C Griel Jr., Thesis Honors Advisor
Subhashinie Kariyawasam, Thesis Supervisor - Keywords:
- Salmonella
Salmonella enteritidis
antibiotics
antibiotic resistance
poultry
broiler
broilers
avian - Abstract:
- Salmonella enterica, a group of rod-shaped, Gram-negative bacteria is a leading cause of foodborne illness in humans. Although more than 2,600 serovars of the bacteria exist, Salmonella enterica serovar Enteritidis is one of the most common causes of foodborne salmonellosis in humans primarily spread through contaminated shell eggs, egg products, and other poultry products. Antimicrobial resistance among foodborne bacterial pathogens like Salmonella species has become an ongoing public health issue. In order to assess the degree of antibiotic resistance in Salmonella Enteritidis (SE), this study sought to analyze antibiotic resistance patterns and several genes known to be involved in the expression of antibiotic resistance in SE. A total of eighty nine SE isolates recovered from diseased broiler chickens submitted to The Pennsylvania State University’s Animal Diagnostic Laboratory were examined for their susceptibility to 26 antibiotics using Kirby Bauer disc diffusion test and for the presence of the marRAB operon (Multiple Antibiotic Resistance) genes, which are known to regulate resistant gene expression in some bacteria, by polymerase chain reaction. The tested isolates were also subjected to pulsed-field gel electrophoresis (PFGE) to determine if there is any association between PFGE fingerprint patterns and antimicrobial resistance profiles of SE. Although all the isolates contained the marRAB operon genes, only very few isolates (4.49%) showed any resistance to the antibiotics used in the study. Furthermore, no correlation was made between antibiotic resistant profiles and PFGE types. Regardless of the lack of relationships found, the study showed that only a small amount of isolates displayed resistance to antibiotics despite the growing threat of antibiotic resistance. Thus, although antibiotic resistance is a prevalent issue in food animal production, the results obtained showed no significant role of resistance in clinical isolates of SE isolated from broiler chickens.