Soluble plantain (Musa paradisiaca) nonstarch polysaccharides (NSPs) have previously been shown to prevent pathogenic interaction with the intestinal epithelium. Here, we examined whether plantain NSP could prevent the invasion of the intestinal mucosa by Salmonella enterica Gallinarum, a causative agent of fowl typhoid. In vitro assays using B1OXI cells were performed with monolayers pretreated with/without plantain NSP, before inoculation with Salm. Gallinarum 287/91. Chicks were fed from hatch on a pellet diet containing 50 mg day−1 plantain NSP, followed by oral inoculation with Salm. Gallinarum 287/91 at the age of 6 days. Bacteria were enumerated from the liver, spleen and caecal contents 3 days postinfection. Adhesion and invasion of Salm. Gallinarum to B1OXI cells were inhibited by 10 mg ml−1 plantain NSP (reduction in invasion 52%; 95% CI 27–77; P < 0·05). In vivo diet supplemented with 50 mg day−1 plantain NSP reduced the invasion of Salm. Gallinarum in the chick liver (control 4·05 Log10 CFU g−1, SE 0·28, vs plantain 2·07 Log10 CFU g−1, SE 0·65; P < 0·01) and nonsignificantly in the spleen. Conversely, CFUs were significantly increased in the caeca (control 1·27 Log10 CFU g−1, SE 0·65, vs plantain 6·04 Log10 CFU g−1, SE 0·17; P < 0·001). Plantain NSP feed reduced the systemic infection by Salm. Gallinarum and may have potential in reducing the impact of the disease in avian salmonellosis. The caveat is the increased caecal load of Salm. Gallinarum, although this may reflect both the reduced intestinal invasion and the bacterial multiplication in the caeca.Significance and Impact of the Study
Nonstarch polysaccharide (NSP) derived from the plantain (Musa paradisiaca) inhibits interaction with epithelial cells by Salmonella enterica Gallinarum, a causative agent of the disease fowl typhoid. Incorporation of plantain NSP into the poultry feed reduced Salm. Gallinarum levels in the spleen and liver of chicks following experimental infection, although their numbers in the caeca increased. These data demonstrate that alternatives to antimicrobials such as NSP may be useful in the control of invasive salmonellosis in poultry.