Prevalence Of Salmonella Species, Clostridium Perfringens, And Clostridium Difficile In The Feces Of Healthy Elephants (Loxodonta Species And Elephas Maximus) In Europe

Pathogenic Salmonella spp., Clostridium perfringens, and Clostridium difficile have been reported to infect and cause severe enteritis and enterotoxemia in African (Loxodonta spp.) and Asian elephants (Elephas maximus). However, little information exists on whether healthy elephants carry and possibly shed these gastrointestinal organisms. This study was conducted to investigate the prevalence of all three bacteria in feces from healthy elephants in European zoos. Bacterial identification was performed by selective culture on fecal samples and a polymerase chain reaction (PCR) amplification protocol, on the basis of primers targeting the hilA gene (Salmonella spp.), the cpa gene (C. perfringens), and the tpi gene (C. difficile) from deoxyribonucleic acid extracted from elephant feces. The PCR protocol was validated prior to initiation of the investigation. Fecal samples collected from 50 African and 86 Asian elephants originating from 30 European zoologic institutions were investigated. The PCR validation revealed detection limits ranging from 10 4 to 10 6 colony-forming units per gram of feces of each gene. Only C perfringens (one type A and two type E) was detected in the initial sampling (2.2%, three Asian elephants), whereas no Salmonella spp. or C. difficile was detected. At a follow-up sampling from C. perfringens-positive animals and relatives, 2 mo after the initial sampling, three animals were culture positive for Salmonella enterica spp. enterica. All positive samples were obtained with bacterial culture, whereas no PCR reactions were positive. Despite carrying these pathogens, all culture-positive animals were clinically healthy and did not develop signs of gastrointestinal disease during the study period. The findings indicate that prevalence of Salmonella spp., C. perfringens, and C. difficile in feces from healthy Asian and African elephants in Europe is very low.