Transcriptional profiling of cecal gene expression in probiotic- and Salmonella- challenged neonatal chicks

Abstract

Probiotics are currently used to improve health and reduce enteric pathogens in poultry. However, the mechanisms by which they reduce or prevent disease are not known. Salmonella are intracellular pathogens that cause acute gastroenteritis in humans, and infections by nontyphoid species of Salmonella also can result in diarrhea, dehydration, and depression in poultry. Frequently, however, no clinical signs of infection are apparent in poultry flocks. In this study, day-of-hatch chicks were challenged with Salmonella enterica serovar Enteritidis (SE) and treated 1 h later with a poultry-derived, Lactobacillus-based probiotic culture (FloraMax-B11, Pacific Vet Group USA Inc., Fayetteville, AR). Cecae were collected 12 and 24 h posttreatment for Salmonella detection and RNA isolation for microarray analysis of gene expression. At both 12 and 24 h, SE was significantly reduced in chicks treated with the probiotic as compared with the birds challenged with only SE (P < 0.05). Microarray analysis revealed gene expression differences among all treatment groups. At 12 h, 170 genes were expressed at significantly different levels (P < 0.05), with a minimum difference in expression of 1.2-fold. At 24 h, the number of differentially regulated genes with a minimum 1.2-fold change was 201. Pathway analysis revealed that at both time points, genes associated with the nuclear factor kappa B complex, as well as genes involved in apoptosis, were significantly regulated. Based on this analysis, probiotic-induced differential regulation of the genes growth arrest-specific 2 (GAS2) and cysteine-rich, angiogenic inducer, 61 (CYR61) may result in increased apoptosis in the cecae of chicks. Because Salmonella is an intracellular pathogen, we suggest that increased apoptosis may be a mechanism by which the probiotic culture reduces Salmonella infection.

Immune modulation by Bacillus subtilis-based direct-fed microbials in commercial broiler chickens

“…or clostridial disease, i.e., NE (Geier et al, 2010;Chen et al, 2012;El Kady et al, 2012;Levkut et al, 2012;Zhang et al, 2012) in chickens. As expected, DFMs modulated host protective immunity against Salmonella infection (Higgins et al, 2011;Levkut et al, 2012).…”

Probiotics for Human and Poultry Use in the Control of Gastrointestinal Disease: A Review of Real-World Experiences

“…Tellez et al evaluated methods to select for individual enteric bacteria capable of inhibiting Salmonella growth in vitro and the ability of selected oxygen tolerant bacteria, in combination, to protect neonatal poults from Salmonella infection following challenge [24,65,66]. Concurrently, they also worked toward the isolation, selection, further evaluation and combination of LAB to control additional foodborne pathogens.…”

“…Probiotic-induced differential regulation of the genes GAS2 and CYR61 may result in increased apoptosis in the ceca of chicks. Because Salmonella is an intracellular pathogen, it was suggested that increased apoptosis may be a mechanism by which B11 reduces Salmonella infection [66].…”

Salmonella’ya Maruz Kalan Erkek Broyler Piliçlerde ThreonineLysine Oranındaki Artışın Performans, Kan Parametreleri ve Humoral İmmun Tepki Üzerine Etkileri

“…All chickens of four replications of each treatment individually infected by oral gavage using an animal feeding needle with equal numbers of Salmonella Paratyphi A (5×10 4 cfu/ml per bird) at the age of 32-d of old [25] . In a 2×3 factorial arrangement, other four replications of each treatment received normal saline.…”

“…Cloacae samples were streaked for isolation onto xylose lysine deoxycholate (XLD, Sigma-Aldrich, UK) agar plates containing tylosin (20 µg/mL) and incubated for 24 and 48 h at 37°C. Plates were evaluated for the presence or absence of Salmonella, which grow as red colonies on this selective medium [25][26][27] .…”