Ameliorative effect of Bacillus subtilis, Saccharomyces boulardii, oregano, and calcium montmorillonite on growth, intestinal histology, and blood metabolites on Salmonella-infected broiler chicken.

This study evaluated the effects of Bacillus subtilis, Saccharomyces boulardii, oregano, and calcium montmorillonite on the physical growth, intestinal histomorphology, and blood metabolites in Salmonella-challenged birds during the finisher phase. In this study, a total of 600 chicks (Ross 308) were randomly distributed into the following dietary treatments: basal diet with no treatment; infected with Salmonella; T1, infected + avilamycin; T2, infected + Bacillus subtilis; T3, Saccharomyces boulardii; T4, infected + oregano; T5, infected + calcium montmorillonite. Our results indicated that feed consumption, body weight gain, total body weight, and feed conversion ratio increased significantly (P < 0.01) in T1 and T2. Villus width increased significantly (P < 0.01) in T1 while the total area was significantly (P < 0.01) higher in T1 and T2 among the treatment groups. Blood protein was significantly (P < 0.01) high in T3 and T4; however, the glucose concentration was significantly (P < 0.01) high in T2, T3, and T4. The treatments increased significantly (P< 0.01) in the treatment groups compared to the negative control. Aspirate aminotransferase (AST) was significantly (P < 0.05) low in T3 compared to the positive control. In conclusion, the results indicated that supplementation of Bacillus subtilis and calcium montmorillonite improved the production performance compared to other feed additives in broiler chicks infected with Salmonella during the finisher phase.

The effect of dietary fructooligosaccharide supplementation on growth performance, intestinal morphology, and immune responses in broiler chickens challenged with Salmonella Enteritidis lipopolysaccharides.

This study was conducted to examine the effects of fructooligosaccharide (FOS) supplementation on growth performance, lymphoid organ weight, intestinal morphology, and immunological status in broilers (n=180) challenged with Salmonella Enteritidis lipopolysaccharides (LPS). Birds were randomly assigned into a 3×2 factorial arrangement that included 1) 3 dietary treatments from d one to 21: positive control (PC), wheat-corn-soybean meal based diet contained antibiotics (virginiamycin and monensin); negative control (NC), as PC without antibiotics; and NC+FOS, as NC supplemented with 0.5% FOS, and 2) 2 intraperitoneal injections: 2 mg/kg Salmonella Enteritidis LPS or sterile phosphate buffered saline (PBS) on d 21. Growth performance and relative lymphoid organ weight were not significantly different among the treatments. Villus height, crypt depth, and total mucosa thickness were significantly increased (P<0.05) in the ileum of broiler chickens fed NC+FOS when compared to PC and NC. Birds in NC+FOS treatment had reduced heterophil but increased monocyte count when compared to NC (P<0.05). Significant diet×challenge interaction was observed on natural IgY levels (P<0.0001), and a significant dietary effect was observed on specific IgY levels in chickens fed NC+FOS (P=0.003). Supplementation of FOS also increased the expression of interleukin (IL)-1ß, -10, and interferon (IFN)-γ mRNA in the ileum of the birds. In summary, Salmonella Enteritidis LPS challenge established significant differences in the immune responses in broiler chickens. FOS supplementation increased ileal mucosa thickness and elevated the expressions of certain cytokine genes. It also led to the alteration of leukocyte compositions and serum IgY levels in response to LPS challenge, suggesting FOS supplementation may be effective to induce protective outcomes in gut health and immunity of broiler chickens.

Evaluation of yeast dietary supplementation in broilers challenged or not with Salmonella on growth performance, cecal microbiota composition and Salmonella in ceca, cloacae and carcass skin.

The dietary supplementation of Saccharomyces cerevisiae var. boulardii was evaluated in broilers challenged or not challenged with Salmonella Enteritidis (SE) using a 2 × 2 factorial arrangement. Depending on yeast inclusion at 0 (C) or 1 × 109 cfu/kg diet (Y) and SE challenge (0 or log 6.3 cfu/bird) on d 15, the experiment had four treatments C, Y, C-SE, and Y-SE, respectively. Each treatment had seven replicate floor pens with 15 broilers. Growth performance responses were determined weekly and overall for the 5 week experimental period. Salmonella levels and prevalence in ceca, cloacae, and carcass skin were determined by culture procedures, while cecal microbiota was determined by real time PCR. Yeast supplementation had no effect (PY > 0.05) on growth performance. For the overall post SE-challenge period (i.e., wk 3 to wk 5), Salmonella reduced body weight gain (BWG) (PSE < 0.001), feed intake (FI) (PSE = 0.032), and the European production efficiency (EPEF) factor (PSE = 0.005). Broilers Y-SE had higher (P < 0.001) overall BW gain compared to C-SE ones. Overall mortality was 2.14% and did not differ (P > 0.05) between treatments. Reduced Salmonella levels in the cloacae (P = 0.014) and on the breast skin (P = 0.006) and lower prevalence on the neck skin (P = 0.007) were noted for treatment Y-SE compared to C-SE. Yeast supplementation did not have an effect (P > 0.05) on cecal microbiota composition at d 1 and d 21 post SE-challenge. On the contrary, SE-challenge reduced cecal levels of total bacteria (PSE = 0.002), E. coli (PSE = 0.006), Bifidobacterium spp. (PSE = 0.006), Bacteroides spp. (PSE = 0.010), and Clostridial populations belonging to cluster I and cluster XIVa, (PSE = 0.047 and PSE = 0.001, respectively) on d 1 post SE-challenge. At 21 d post SE-challenge, only the levels of cecal Lactobacillus spp. (PSE = 0.001) and Bifidobacterium spp. (PSE = 0.049) were reduced compared to the non SE-challenged groups. In conclusion, yeast supplementation in SE challenged broilers (Y-SE) was beneficial for growth performance and reduced Salmonella presence compared to C-SE ones. The disturbance of cecal microbiota balance by SE merits further investigation for potential implications in gut and overall bird health.

Reduction of subclinical Salmonella infection in fattening pigs after dietary supplementation with a ß-galactomannan oligosaccharide.

AIMS: To assess the efficacy of a ß-galactomannan oligosaccharide (ß-GMOS) for the control of Salmonella infection in fattening pigs. METHODS AND RESULTS: Three different doses (0.5, 3 and 2 kg ß-GMOS per ton of feed) were used during the entire period of growing in three similar and independent field trials carried out in a small fattening unit (≈ 100 pigs). Treatment was randomly assigned to half of the pens. Individual serum samples (20-25 per group) were collected at different times during the fattening period and a similar number of faecal samples during the fattening period and at slaughter. In addition, mesenteric lymph nodes were collected at slaughter. Herdcheck(®) Swine Salmonella ELISA was used for serological analyses, the ISO 6579:2002/Amd 1 : 2007 for bacteriology and the PFGE for molecular characterization of Salmonella strains. The addition of ≥ 2 kg t(-1) of ß-GMOS to the pig diet during the entire fattening period was associated with a reduction in Salmonella prevalence, shedding and seroconversion. CONCLUSIONS: Feed supplementation with ß-GMOS may be a useful complementary tool for the control of salmonellosis in fattening pigs. SIGNIFICANCE AND IMPACT OF THE STUDY: ß-GMOS may be a complementary way of reducing Salmonella shedding and infection in fattening pigs.

Comparison of prophylactic or therapeutic dietary administration of capsaicin for reduction of Salmonella in broiler chickens.

In three experiments the effects of prophylactic or therapeutic dietary inclusion of capsaicin, the pungent component of peppers, were evaluated as a nonantibiotic alternative for reduction of Salmonella in broiler chickens through culture and morphologic assessment of cecal tissue. Expt. 1 evaluated the effects of 0 or 10 ppm purified capsaicin (CAP) in the starter phase (days 1-16) on chicks challenged with Salmonella Enteritidis (SE) on day of age. Therapeutic inclusion of 10 ppm purified CAP increased (P < 0.05) liver/spleen (L/S) and ceca positive results for SE. In Expt. 2, capsaicin oleoresin (CO) was included in the finisher diet (days 30-37) at 0, 5, or 20 ppm with SE challenge on day 31. Inclusion of 5 ppm CO increased ceca positive results for SE, and a linear decrease in cecal lamina propria thickness of SE-challenged birds was observed with increased CO concentration in the diet. Expt. 3 evaluated prophylactic CO treatment at 0, 5, or 20 ppm in starter, grower, and finisher diets for resistance to SE or Salmonella Typhimurium (ST) challenge on day 14 or 29. With challenge on day 14, 5 and 20 ppm prophylactic CO feeding reduced ceca SE positive results by 37% and 26%, respectively, and ST culture rate was reduced similarly with 5 ppm CO. Lamina propria thickness of the ceca increased with 5 ppm CO feeding in SE-challenged birds, whereas a decrease was observed in nonchallenged birds fed 5 ppm CO. Challenge on day 29 of birds fed 20 ppm CO resulted in reduced L/S positive results for SE. Lamina propria thickness decreased with 5 ppm CO and SE or ST challenge compared with nonchallenged birds fed 5 ppm. An increase was observed in ST- or SE-challenged birds fed 20 ppm CO compared with nonchallenged birds fed 20 ppm CO. No differences were observed in mast cell number in either Expt. 2 or 3. These data provide evidence that prophylactic or therapeutic dietary capsaisin differentially affects broiler susceptibility to Salmonella.

Protective effects of dietary lactulose and calcium phosphate against Salmonella infection.

BACKGROUND: Protection against intestinal infections by lactulose fermentation might be enhanced by calcium phosphate, due to the increased buffering capacity and/or inhibition of the cytotoxicity of luminal contents. METHODS: SPF rats were fed a low-calcium control diet, a low-calcium/lactulose diet or a high-calcium/lactulose diet and orally infected with Salmonella enteritidis. Faeces and urine were sampled for microbiological and chemical analyses. RESULTS: The lactulose-fed rats had a better colonization resistance. Translocation was reduced by dietary calcium, whereas lactulose was ineffective. In addition, calcium supplementation stimulated lactulose fermentation, reversed the lactulose-induced increase in cytotoxicity of faecal water and normalized growth and faecal consistency. CONCLUSIONS: The combination of dietary lactulose and calcium phosphate is protective against Salmonella infection.