Prevalence of Multidrug Resistance among Salmonella enterica Serovar Typhimurium Isolated from Pig Faeces in Ashanti Region, Ghana

Abstract

Introduction. Salmonella typhimurium is associated with outbreaks of food-borne nontyphoidal salmonellosis (NTS) worldwide with marked multidrug resistance. Objectives. This study aimed to determine the prevalence of antibiotic resistant Salmonella typhimurium in pigs in Ashanti Region, Ghana. Methods. Faeces from 10 pigs per pig farm were collected and mixed to obtain 108 multiply-composite faecal samples. Standard microbiology and biochemical procedures were used to isolate and identify an S. typhimurium isolate from the composite faecal sample of each farm. Antibiotic sensitivity test was carried out to determine the sensitivity of the isolates. Discussion. From the 108 multiply-composite faecal samples, 72 S. typhimurium isolates were obtained from 72 separate composite samples representing 72 different pig farms. Of the 72 faecal isolates, 32 (52.8%) were resistant to at least one antibiotic. Twenty-seven isolates (71.1%) were resistant to amoxicillin and streptomycin. Resistance to tetracycline, doxycycline, and ciprofloxacin was found in 17 (44.7%), 15 (39.5%), and 8 (21.1%) isolates, respectively. Resistance to norfloxacin, sulphamethoxazole-trimethoprim, and gentamicin were expressed in 3 (7.9%), 3 (7.9%), and 0 (0.0%) isolates, respectively. Conclusion. Multiple drug resistance is common in S. typhimurium isolates, many of which could belong to the same clone, from pigs in Ashanti Region, Ghana.