PREVALENCE OF SALMONELLA SPECIES, CLOSTRIDIUM PERFRINGENS, AND CLOSTRIDIUM DIFFICILE IN THE FECES OF HEALTHY ELEPHANTS (LOXODONTA SPECIES AND ELEPHAS MAXIMUS) IN EUROPE

Conserved core microbiota in managed and free-ranging Loxodonta africana elephants

The gut microbiota plays a crucial role in animal health and homeostasis, particularly in endangered species conservation. This study investigated the fecal microbiota composition of European captive-bred African savanna elephants (Loxodonta africana) housed in French zoos, and compared it with wild African savanna elephants. Fecal samples were collected and processed for DNA extraction and amplicon sequencing of the 16S rRNA gene. The analysis of α and β diversity revealed significant effects of factors such as diet, daily activity, and institution on microbiota composition. Specifically, provision of branches as part of the diet positively impacted microbiota diversity. Comparative analyses demonstrated distinct differences between captive and wild elephant microbiomes, characterized by lower bacterial diversity and altered co-occurrence patterns in the captive population. Notably, specific taxa were differentially abundant in captive and wild elephants, suggesting the influence of the environment on microbiota composition. Furthermore, the study identified a core association network shared by both captive and wild elephants, emphasizing the importance of certain taxa in maintaining microbial interactions. These findings underscore the impact of environment and husbandry factors on elephant gut microbiota, highlighting the benefits of dietary enrichment strategies in zoos to promote microbiome diversity and health. The study contributes to the broader understanding of host-microbiota interactions and provides insights applicable to conservation medicine and captive animal management.

Salmonellosis in elephants in managed care: report of 2 cases and literature review

In animals, salmonellosis is seen typically as enteritis and/or septicemia. Subclinical infection also occurs, and outwardly healthy animals can serve as reservoirs of infection. Reports of salmonellosis in elephants are rare, limited to a few serovars, and the gross and microscopic lesions of enteric salmonellosis in this species have not been described in detail. We present here, in 2 elephants in managed care settings, cases of salmonellosis that resulted from infection by Salmonella enterica serovar Muenchen and S. enterica serovar Montevideo, serovars that have not been described previously as the cause of salmonellosis in elephants, to our knowledge. We also review the literature on salmonellosis in elephants. Animal A, an adult Asian elephant that was euthanized because of gastrointestinal hemorrhage, had multifocal, necrotizing, suppurative enterocolitis, and necrotizing gastritis. Animal B, an adult African elephant with chronic, recurrent colic, followed by death, had necrotizing typhlocolitis. The origin of infection was not determined in either case. The animals came from different facilities and did not have a common feed source. Previously reported cases of salmonellosis in elephants were caused by Salmonella Dublin, Salmonella Typhimurium, or Salmonella Enteritidis. The definitive diagnosis of salmonellosis is made based on compatible gross and microscopic lesions, coupled with the detection of Salmonella spp. in the affected tissues. Effective biosecurity should be adopted to minimize the risk of salmonellosis in elephants in managed care.

Colonic sand impaction with cecal rupture and peritonitis in an adult African savanna elephant, and review of noninfectious causes of gastrointestinal disease in elephants

Gastrointestinal disorders are among the most common disease processes in captive elephants. Colic is a frequent clinical presentation and may have several infectious and noninfectious causes. Ingestion of sand has been reported in elephants living in enclosures with loose sandy soils. Similar to the situation in horses, sand ingestion can cause intestinal impaction and colic in elephants. Here we describe a case of colonic sand impaction with cecal rupture and peritonitis in an African savanna elephant from a zoologic collection that died after several days of colic. On autopsy, abundant, gritty, sandy material was found within a segment of colon immediately aboral to the cecum. There was a full-thickness tear in the cecal wall, free intestinal contents within the abdominal cavity, and peritonitis. To our knowledge, the postmortem examination of an elephant with sand impaction and cecal rupture has not been reported previously; this condition should be included among the differential diagnoses in elephants with colic. We review the reports of noninfectious causes of gastrointestinal disease in elephants, which include cases of small intestinal and colonic torsion and of intestinal obstruction by fecal boluses.

Elephant Endotheliotropic Herpesvirus 4 and Clostridium perfringens Type C Fatal Co-Infection in an Adult Asian Elephant (Elephas maximus)

Elephant endotheliotropic herpesvirus hemorrhagic disease (EEHV-HD) is an acute, often fatal, multisystemic hemorrhagic disease and one of the most significant causes of mortality of Asian elephants in captivity. Most fatal cases of EEHV-HD are associated with EEHV1A and EEHV1B in juveniles. This case report describes the clinical and pathological features of a fatal co-infection of Clostridium perfringens type C and EEHV-HD, caused by EEHV4, in an adult female Asian elephant. Although fatal clostridial enterotoxemia has been occasionally reported in elephants, this report highlights the importance of having both EEHV-HD and clostridial enterotoxemia as potential differential diagnoses in cases of widespread tissue necrosis and internal hemorrhage in elephants, regardless of the animal age group, due to their macroscopic similarities, frequent co-occurrence and cumulative morbid potential.