Wild fauna as a carrier of Salmonella in Reunion Island: Impact on pig farms

Abstract

Salmonellosis is an economic burden to the livestock industry in Reunion Island. In this study, we wanted to improve our understanding of Salmonella epidemiology by studying the wild fauna of Reunion Island. We assessed Salmonella diversity in small non-flying mammals, birds and cockroaches in order to evaluate their potential role in the epidemiology of Salmonella. A total of 268 samples were collected from cockroaches, small mammals and birds. The bacteriological analyses revealed that 11.7% of non-flying mammals and 25% of cockroaches tested were Salmonella infected; two wild bird species were also detected positive. The 128 Salmonella isolates were distributed in fifteen serotypes and the most predominant were S. 4,[5],12:i:- (21.9% of positive samples) followed by S. Enteritidis (15.6%), S. Typhimurium (15.6%), S. Infantis (12.5%) and S. Weltevreden (12.5%). A total of 27 XbaI profiles were identified using pulsed-field gel electrophoresis. Comparison of these Salmonella strains with our collection of Salmonella isolated from pigs and pig farm environments at the same period revealed 14 strains in common between wild fauna and pigs, especially for cockroaches. Our results suggest that wild fauna of Reunion Island could be infected by strains of Salmonella also isolated from pigs or pig environment. They may play a role in both persistence and spreading of Salmonella and therefore, could be a source of infection in pig farms. Pest control against cockroaches could be a helpful tool in the reduction of Salmonella infection of pigs, limiting contacts between wild fauna and both pigs and pig environment. Special attention should be paid to S. 4,[5],12:i:- since it was predominant in Reunion Island's wild fauna and pigs and was the third most frequently reported serotype in human salmonellosis in Europe.

Identification of Rodent Species That Infest Poultry Houses in Mafikeng, North West Province, South Africa

“…It may also carry important protozoa which are mainly dangerous for immune compromised patients [1]. Bacterial pathogens like Salmonella that are important to both humans and livestock have also been isolated from R. rattus in many countries, i.e., Japan, [25], Reunion Island [26], Pakistan [27], and Canada [14]. In the phylogenetic tree it clustered well with the species found in India, Jordan, Tanzania, and other South African studies.…”

Salmonella spp. in Wild Free-Living Birds from Atlantic Forest Fragments in Southern Bahia, Brazil

“…The research conducted with 62 wild birds, namely 30 Columba livia, 19 Pterodroma baraui, 10 Puffinus lherminieri, and three Phaethon lepturus, from industrial sites and rescue centers, and found that only one specimen of two species each tested positive for Salmonella spp. [31]. The study with 364 Passeriformes and Piciformes found no positive isolate for Salmonella spp.…”

Diversity of Salmonella serotypes from humans, food, domestic animals and wildlife in New South Wales, Australia

“…Given the documented wide host range of S . Typhimurium [ 25 – 27 ], it was unsurprising that it was a common serotype in all livestock and all associated food commodities. Nevertheless, eggs remain the most commonly implicated food in outbreaks of this serotype [ 2 , 15 ].…”