Reduction of Salmonella Typhimurium Cecal Colonisation and Improvement of Intestinal Health in Broilers Supplemented with Fermented Defatted ‘Alperujo’, an Olive Oil By-Product

SIMPLE SUMMARY: Salmonella spp. is a bacterium that places human health at risk by consuming eggs and poultry. In the European Union, the use of antimicrobials to treat salmonellosis in aviculture is no longer permitted due to the resistance to treatment of some bacteria, such as Salmonella spp. For this reason, compounds derived from natural food sources are being increasingly tested to assess their efficacy against Salmonella spp. In this study, chickens were given dietary supplements in the form of fermented defatted ‘alperujo’, a modified olive oil by-product, after which they were infected with Salmonella Typhimurium. The chickens given the supplement showed a healthy gut and a reduction in the amount of Salmonella spp. in the cecum. In conclusion, this olive oil by-product may contribute to preventing and controlling salmonellosis in farms, as well as reducing environmental contamination. ABSTRACT: Salmonella spp. contaminates egg and poultry meat leading to foodborne infections in humans. The emergence of antimicrobial-resistant strains has limited the use of antimicrobials. We aimed to determine the effects of the food supplement, fermented defatted ‘alperujo’ (FDA), a modified olive oil by-product, on Salmonella Typhimurium colonisation in broilers. One hundred and twenty 1-day-old broilers were divided into four experimental groups—two control groups and two treated groups, and challenged with S. Typhimurium at day 7 or 21. On days 7, 14, 21, 28, 35, and 42 of life, duodenum and cecum tissue samples were collected for histopathological and histomorphometric studies. Additionally, cecum content was collected for Salmonella spp. detection by culture and qPCR, and for metagenomic analysis. Our results showed a significant reduction of Salmonella spp. in the cecum of 42-day-old broilers, suggesting that fermented defatted ‘alperujo’ limits Salmonella Typhimurium colonization in that cecum and may contribute to diminishing the risk of carcass contamination at the time of slaughter. The improvement of the mucosal integrity, observed histologically and morphometrically, may contribute to enhancing intestinal health and to limiting Salmonella spp. colonisation in the host, mitigating production losses. These results could provide evidence that FDA would contribute to prophylactic and therapeutic measures to reduce salmonellosis prevalence in poultry farms.