Protective effects of sodium humate and its zinc and selenium chelate on the oxidative stress, inflammatory, and intestinal barrier damage of Salmonella Typhimurium-challenged broiler chickens.

The objective of this study was to investigate the protective effects and mechanisms of dietary administration of sodium humate (HNa) and its zinc and selenium chelate (Zn/Se-HNa) in mitigating Salmonella Typhimurium (S. Typhi) induced intestinal injury in broiler chickens. Following the gavage of 109 CFU S. Typhi to 240 broilers from 21-d to 23-d aged, various growth performance parameters such as body weight (BW), average daily gain (ADG), average daily feed intake (ADFI), and feed ratio (FCR) were measured before and after infection. Intestinal morphology was assessed to determine the villus height, crypt depth, and chorionic cryptologic ratio. To evaluate intestinal barrier integrity, levels of serum diamine oxidase (DAO), D-lactic acid, tight junction proteins, and the related genes were measured in each group of broilers. An analysis was conducted on inflammatory-related cytokines, oxidase activity, and Nuclear Factor Kappa B (NF-κB) and Nuclear factor erythroid2-related factor 2 (Nrf2) pathway-related proteins and mRNA expression. The results revealed a significant decrease in BW, ADG, and FCR in S. typhi-infected broilers. HNa tended to increase FCR (P = 0.056) while the supplementation of Zn/Se-HNa significantly restored BW and ADG (P < 0.05). HNa and Zn/Se-HNa exhibit favorable and comparable effects in enhancing the levels of serum DAO, D-lactate, and mRNA and protein expression of jejunum and ileal tight junction. In comparison to HNa, Zn/Se-HNa demonstrates a greater reduction in S. Typhi shedding in feces, as well as superior efficacy in enhancing the intestinal morphology, increasing serum catalase (CAT) activity, inhibiting pro-inflammatory cytokines, and suppressing the activation of the NF-κB pathway. Collectively, Zn/Se-HNa was a more effective treatment than HNa to alleviate adverse impact of S. Typhi infection in broiler chickens.

Addition of a protected complex of biofactors and antioxidants to breeder hen diets confers transgenerational protection against Salmonella enterica serovar Enteritidis in progeny chicks.

Addition of vitamins and antioxidants has been long associated with increased immunity and are commonly used in the poultry industry; however, less is known regarding their use in broiler breeder hens. The objective of this study was to determine if feeding a complex of protected biofactors and antioxidants composed of vitamins and fermentation extracts to broiler breeder hens conferred resistance against Salmonella enterica serovar Enteritidis (S. Enteritidis) in the progeny chicks. Three-day-old chicks from control- and supplement-fed hens were challenged with S. Enteritidis and necropsied 4- and 11-days postchallenge (dpc) to determine if there were differences in invasion and colonization. Serum and jejunum were evaluated for various cytokine and chemokine production. Fewer (P = 0.002) chicks from supplement-fed hens had detectable S. Enteritidis in the ceca (32.6%) compared to chicks from control-fed hens (64%). By 11 dpc, significantly (P < 0.001) fewer chicks from supplement-fed hens were positive for S. Enteritidis (liver [36%]; ceca [16%]) compared to chicks from the control hens (liver [76%]; ceca [76%]). The recoverable S. Enteritidis in the cecal content was also lower (P = 0.01) at 11 dpc. In additional to the differences in invasion and colonization, cytokine and chemokine production were distinct between the 2 groups of chicks. Chicks from supplement-fed hens had increased production of IL-16, IL-6, MIP-3α, and RANTES in the jejunum while IL-16 and MIP-1ß were higher in the serum of chicks from the control-fed hens. By 11 dpc, production of IFN-γ was decreased in the jejunum of chicks from supplement-fed hens. Collectively, these data demonstrate adding a protected complex of biofactors and antioxidants to the diet of broiler breeder hens offers a measure of transgenerational protection to the progeny against S. Enteritidis infection and reduces colonization that is mediated, in part, by a robust and distinct cytokine and chemokine response locally at the intestine and systemically in the blood.

Antimicrobial and immunomodulatory effects of tannic acid supplementation in broilers infected with Salmonella Typhimurium.

Infection by Salmonella Typhimurium, a food-borne pathogen, can reduce the poultry production efficiency. The objective of this study was to investigate the effects of tannic acid (TA) supplementation on growth performance, Salmonella colonization, gut barrier integrity, serum endotoxin levels, antioxidant capacity, gut health, and immune function in broilers infected with the Salmonella enterica serovar Typhimurium nalidixic acid resistant strain (STNR). A total of 546 one-day-old broilers were arbitrarily allocated into 6 treatments including 1) Sham-challenged control (SCC; birds fed a basal diet and administrated peptone water); 2) Challenged control (CC; birds fed a basal diet and inoculated with 108 STNR); 3) Tannic acid 0.25 (TA0.25; CC + 0.25 g/kg TA); 4) TA0.5 (CC + 0.5 g/kg TA); 5) TA1 (CC + 1 g/kg TA); and 6) TA2 (CC + 2 g/kg TA). On D 7, supplemental TA linearly reduced STNR colonization in the ceca (P < 0.01), and TA1 and TA2 group had significantly lower reduced STNR colonization in the ceca (P < 0.01). On D 7 to 21, average daily gain tended to be linearly increased by supplemental TA (P = 0.097). The serum endotoxin levels were quadratically decreased by supplemental TA on D 21 (P < 0.05). Supplemental TA quadratically increased ileal villus height (VH; P < 0.05), and the TA0.25 group had higher ileal VH compared to the CC group (P < 0.05). Supplemental TA linearly increased percentage of peripheral blood CD8+ T cells on D 18 (P < 0.01). The TA0.5 group had significantly lower lymphocyte numbers compared to the CC groups (P < 0.05). The abundance of monocytes linearly increased with TA supplementation (P < 0.01). Therefore, broilers fed TA had reduced STNR colonization, increased growth performance, decreased serum endotoxin levels, enhanced gut health in the broilers, and stimulated the immune system in broilers infected with STNR. Supplementation of TA (1-2 g/kg) enhanced growth performance and gut health via antimicrobial and immunostimulatory effects in broilers infected with STNR.

Short Chain Fatty Acids and Bacterial Taxa Associated with Reduced Salmonella enterica serovar I 4,[5],12:i:- Shedding in Swine Fed a Diet Supplemented with Resistant Potato Starch.

Salmonella enterica serovar I 4,[5],12:i:- is a foodborne pathogen of concern because many isolates are multidrug-resistant (resistant to ≥3 antimicrobial classes) and metal tolerant. In this study, three in-feed additives were individually tested for their ability to reduce Salmonella I 4,[5],12:i:- shedding in swine: resistant potato starch (RPS), high amylose corn starch, and a fatty acid blend, compared with a standard control diet over 21 days. Only RPS-fed pigs exhibited a reduction in Salmonella fecal shedding, different bacterial community compositions, and different cecal short chain fatty acid (SCFA) profiles relative to control animals. Within the RPS treatment group, pigs shedding the least Salmonella tended to have greater cecal concentrations of butyrate, valerate, caproate, and succinate. Additionally, among RPS-fed pigs, several bacterial taxa (Prevotella_7, Olsenella, and Bifidobacterium, and others) exhibited negative relationships between their abundances of and the amount of Salmonella in the feces of their hosts. Many of these same taxa also had significant positive associations with cecal concentrations of butyrate, valerate, caproate, even though they are not known to produce these SCFAs. Together, these data suggest the RPS-associated reduction in Salmonella shedding may be dependent on the establishment of bacterial cross feeding interactions that result in the production of certain SCFAs. However, directly feeding a fatty acid mix did not replicate the effect. RPS supplementation could be an effective means to reduce multidrug-resistant (MDR) S. enterica serovar I 4,[5],12:i:- in swine, provided appropriate bacterial communities are present in the gut. IMPORTANCE Prebiotics, such as resistant potato starch (RPS), are types of food that help to support beneficial bacteria and their activities in the intestines. Salmonella enterica serovar I 4,[5],12:i:- is a foodborne pathogen that commonly resides in the intestines of pigs without disease, but can make humans sick if unintentionally consumed. Here we show that in Salmonella inoculated pigs, feeding them a diet containing RPS altered the colonization and activity of certain beneficial bacteria in a way that reduced the amount of Salmonella in their feces. Additionally, within those fed RPS, swine with higher abundance of these types of beneficial bacteria had less Salmonella I 4,[5],12:i:- in their feces. This work illustrates likely synergy between the prebiotic RPS and the presence of certain gut microorganisms to reduce the amount of Salmonella in the feces of pigs and therefore reduce the risk that humans will become ill with MDR Salmonella serovar I 4,[5],12:i:-.

Green Coffea robusta (Coffea canephora) from Lampung province effect toward free radicals in chickens infected with Salmonella enteritidis bacteria.

Background: Foodborne diseases are caused by acquired pathogenic bacteria such as Salmonella enteritidis. It causes an intestinal imbalance and the microbial toxins found in the gastrointestinal tract induce symptoms such as diarrhea. Coffee contains active ingredients such as antioxidants and is used as an anti-inflammatory agent by reducing pro-inflammatory cytokine levels in the body. Aim: The purpose of this study was to determine the interaction between Lampung's robusta coffee and tissue damage in chickens infected by S. enteritidis. Methods: This study used first-day-old Isa brown layer chickens (n = 60), which were divided into five treatment groups. The negative control group consisted of healthy and normal chickens, whereas the positive control group consisted of chickens infected with S. enteritidis bacteria at a concentration of 108 CFU/ml. Groups T1, T2, and T3 were given coffee extract with doses of 500 mg/kg BW (low dose), 1,000 mg/kg BW (moderate dose), and 1,500 mg/kg BW (high dose), respectively, and then infected with S. enteritidis bacteria at a concentration of 108 CFU/ml. The coffee extract and bacteria were given orally via a feeding tube at a volume of 0.5 ml per chick. The extract was given for 14 days (from day 3 to day 16), and the bacteria were given on days 16 and 17. On day 18, the chickens were necropsied. The malondialdehyde (MDA) level was analyzed using one-way analysis of variance test with the GLM procedure (<0.05), while the tissue histopath was analyzed using a descriptive qualitative study to examine the ileal damage. Results: The results showed that the MDA levels (nmol/l) decreased in treatment groups T1, T2, and T3 compared to the positive control. On the contrary, we found improvements in the ileum histopathology of group T1 and T2 in the form of normal and regular intestinal epithelium arrangement of the ileum, long intestinal villi, and decreased total leukocytes. Conclusion: Green coffee robusta has the potential to increase antioxidants and reduce inflammation in the small intestine of chickens infected with S. enteritidis.

Efficacy of chestnut and quebracho wood extracts to control Salmonella in poultry.

AIMS: The study was aimed to evaluate the antibacterial activity and efficacy of chestnut and quebracho wood extracts against Salmonella by in vitro assays and in vivo trials. METHODS AND RESULTS: The extracts showed inhibitory activity against Salmonella determined by the minimum inhibitory concentration method as well as on the adhesion and invasion of S. Gallinarum (SG) and S. Enteritidis (SE) in Caco-2 cells. Also, transmission electron microscopy revealed that extract-treated Salmonella showed disruption of cell walls and membranes, damage of the cytoplasm and tannin-protein aggregations. In addition, efficacy of the extracts to control SG and SE was evaluated in experimental infection trials in laying hens and broilers respectively. SE excretion was significantly reduced on days 5 (P < 0·01) and 12 (P < 0·025) only in the quebracho group. In the fowl typhoid infection model, hens that received the chestnut extract showed a significantly reduced mortality (P < 0·05). CONCLUSIONS: Our results evidence that these alternative natural products may be a useful tool to control Salmonella in poultry. SIGNIFICANCE AND IMPACT OF THE STUDY: Salmonella is a zoonotic pathogen usually associated with poultry production. This study provides information about the mechanism of antibacterial effects of chestnut and quebracho wood extracts to control Salmonella in poultry.

Evaluation of the efficiency of using Salmonella Kentucky and Escherichia coli O119 bacteriophages in the treatment and prevention of salmonellosis and colibacillosis in broiler chickens.

Phage therapy is considered an alternative modality in the treatment of different bacterial diseases. However, their therapeutic and preventive roles against infections caused by Salmonella Kentucky and Escherichia coli O119 were of little attention. In this study, two phages were isolated, characterized and assessed for their potential therapeutic and preventive roles against S. Kentucky and E. coli O119 infections in broilers. Commercial 1-day-old arboacres broiler chicks were assigned to seven groups: Group Ӏ was as a negative control, groups (П and Ш) were assigned as positive controls by the challenge of S. Kentucky and E. coli O119, respectively. The remaining four groups (IV, V, VI and VII) were administrated with five repeated phage doses to determine the effect of multiple doses. Phages were administrated in groups (IV and VI) after challenging with S. Kentucky and E. coli O119, respectively to assess their therapeutic role; moreover, their preventive role was evaluated through administration in groups (V and VII) before challenging with S. Kentucky and E. coli O119, respectively. Sampling was done from different organs at three time points and revealed that phage-treated groups had lower colony forming units of S. Kentucky and E. coli. Our results suggest that bacteriophages are efficient in the treatment and prevention of salmonellosis and colibacillosis in broiler farms.

Organic acid blend supplementation increases butyrate and acetate production in Salmonella enterica serovar Typhimurium challenged broilers.

The burden of enteric pathogens in poultry is growing after the ban of antibiotic use in animal production. Organic acids gained attention as a possible alternative to antibiotics due to their antimicrobial activities, improved nutrient metabolism and performance. The current study was conducted to evaluate the effectiveness of organic acid blend on broilers cecal microbiota, histomorphometric measurements, and short-chain fatty acid production in Salmonella enterica serovar Typhimurium challenge model. Birds were divided into four treatments, including a negative control, positive control challenged with S. Typhimurium, group supplemented with an organic acid blend, and birds supplemented with organic acid blend and Salmonella challenged. Results illustrate significant differences in feed conversion ratios and production efficiency factor between treatment groups, however, the influence of organic acid supplement was marginal. Organic acid blend significantly increased cecal acetic and butyric acids concentrations when compared to unsupplemented groups and resulted in minor alterations of intestinal bacterial communities.

Supplementing neonatal Jersey calves with a blend of probiotic bacteria improves the pathophysiological response to an oral Salmonella enterica serotype Typhimurium challenge.

The objectives of the current study were to determine the effects of supplementing a blend of probiotic bacteria (Provida Calf, MB Nutritional Sciences, Lubbock, TX) on the pathophysiological response to an oral Salmonella enterica serotype Typhimurium challenge in neonatal Jersey calves. Twenty-four Jersey bull calves within 24 h of birth were acquired from a local calf ranch, blocked by total serum protein and initial body weight, and randomly assigned to 1 of 3 treatments (n = 8). Calves were assigned to either (1) Control (CON); base milk replacer, (2) Control + Salmonella Typhimurium (CON+ST); base milk replacer and challenged with Salmonella Typhimurium on d 7; or (3) Provida Calf probiotics + Salmonella Typhimurium (PRO+ST); same milk replacer supplemented with a proprietary blend of Lactobacillus casei and Enterococcus faecium strains and challenged with Salmonella Typhimurium on d 7. The PRO+ST calves were supplemented for the first 3 d with 2 × 1010 cfu/d and then with 2 × 109 cfu/d for the remainder of the study. The CON+ST and PRO+ST calves were each challenged with approximately 5 × 106 cfu of Salmonella Typhimurium (ATCC# 14028), which was a mild challenge that did not cause scours in the calves. Peripheral blood samples were collected on d 0, 7, 10, 14, and 21 and analyzed for hematology; serum was collected and analyzed for haptoglobin, glucose, and urea N. Rectal temperatures were collected daily from d 6 to 21, when all calves were killed, so that persistent colonization of Salmonella Typhimurium and histomorphology of both the duodenum and ileum could be determined. Serum haptoglobin and urea N concentrations were increased among CON+ST on d 10. In contrast, the peak rectal temperature on d 10 in PRO+ST calves was 40.4°C, which was greater than that for CON and CON-ST (38.9°C and 39.7°C, respectively). The neutrophil percentage in peripheral circulation in PRO+ST calves was 55.4%, which was greater than that for CON and CON+ST (34.8 and 41.8%, respectively). Seven of the 8 PRO+ST calves had elevated neutrophil percentages on d 10 compared with d 7, whereas 4 of the 8 CON+ST calves had reduced neutrophil percentages on d 10 compared with d 7. Villus height-to-crypt depth ratios in the duodenum were greater among CON and PRO+ST calves, being 1.38, 0.84, and 1.43 for CON, CON+ST, and PRO+ST, respectively. In the ileum, the PRO+ST calves had greater villus height-to-crypt depth ratios than both the CON and CON+ST calves (1.64, 1.53, and 2.43 for CON, CON+ST, and PRO+ST, respectively). These data indicate that supplementing neonatal calves with the blend of probiotic bacteria used in the current study can influence the pathophysiological response to a mild enteric Salmonella Typhimurium challenge.

The effect of a selected yeast fraction on the prevention of pullorum disease and fowl typhoid in commercial breeder chickens.

A selected yeast fraction (SYF) was tested for the purpose of preventing pullorum disease and fowl typhoid in breeder chickens. In a challenge-protection experiment, commercial Three-Yellow breeder chicks were initially divided into groups A, B (challenged, treated), C (challenged, untreated), and D (unchallenged, untreated). The group A diet was supplemented with SYF and group B was supplemented with Acidipure via drinking water. At 7 D, birds of groups A, B, and C were divided into 2 equal subgroups (A1-A2, B1-B2, and C1-C2). Subgroups A1, B1, and C1 were challenged with Salmonella pullorum (SP), while subgroups A2, B2, and C2 were challenged with Salmonella gallinarum (SG). Clinical signs and mortality were recorded daily. At intervals, antibodies against SP and SG were detected by a plate agglutinate test (PAT). At 42 D, all birds were weighed and necropsied, lesions were recorded and challenge pathogens were isolated. Results showed that SP and SG isolation positive rates of groups A1-A2 were significantly lower (P < 0.05) than those of B1-B2 and C1-C2, respectively. The average body weight (BW) of groups A1-A2 was significantly higher (P < 0.05) than that of B1-B2 and C1-C2, respectively. In the field trial, chicks were randomly divided into 3 groups. Group 1 birds were fed a diet supplemented with SYF, group 2 diet was supplemented with Acidipure via drinking water, and group 3 was fed the same but un-supplemented diet as the control group. Antibodies against SP and SG were detected by PAT at 120 D. The antibodies positive rate of group 1 was significantly lower (P < 0.05) than those of groups 2 and 3, while no significant difference (P > 0.05) was found between groups 2 and 3. The results demonstrated that SYF supplementation could significantly decrease SP and SG infection rates, improve the BW of birds challenged with SP and SG, and was more effective than Acidipure via drinking water.

Effects of a mannan-rich yeast cell wall-derived preparation on cecal concentrations and tissue prevalence of Salmonella Enteritidis in layer chickens.

Salmonella Enteritidis (SE) has been the most common Salmonella serotype associated with foodborne infections in the last several years. Dietary applications of yeast-based preparations in feed have shown to reduce Salmonella colonization in chickens augmenting SE control strategies. This study was conducted to evaluate the effects of a mannan-rich yeast cell wall-derived preparation (Actigen®) administered in feed at a rate of 400 g/ton on SE colonization in the cecum and internal organs of commercial layer chickens. Sixteen week-old layer pullets were orally challenged with a selected nalidixic acid resistant SE strain at a dose of 1.7×10^9 colony forming units (CFU) per bird. SE colonization was assessed by evaluating isolation rates from ovary and pooled liver/spleen samples as well as enumeration of SE in cecal pouches one week post-challenge. Recovery rates of SE from the ovaries of directly challenged birds receiving Actigen® were significantly lower (P <0.02) than those in directly challenged birds fed an unsupplemented control diet. Recovery rates of SE from pooled liver/spleen samples were not significantly different between Actigen®-treated pullets and controls (P = 0.22). Using direct plate count methods, cecal SE concentrations were 1 log10 lower (P <0.001) in challenged pullets in the Actigen®-supplemented group than in the challenged controls. The SE concentration distributions in the ceca were similar in groups testing positive and groups testing negative for SE in the ovaries and liver/spleens tissues. As a result, SE concentrations in the ceca could not be directly related to the occurrence or prevalence of SE in these tissues. In conclusion, Actigen® supplementation appears to decrease the prevalence of SE in ovarian tissue and concentrations of SE in cecal contents and may be useful as a tool for reducing the risk of eggshell contamination and transovarian transmission of SE in eggs.

The effect of capsulated and noncapsulated egg-yolk-specific antibody to reduce colonization in the intestine of Salmonella enterica ssp. enterica serovar Infantis-challenged broiler chickens.

The antibacterial properties of egg yolk antibodies have been known for many years. Enhanced antibiotic resistance has resulted in increased need for using these antibodies as an alternative. In the present study, generation, capsulation, and inhibition growth properties of IgY directed against Salmonella enterica subsp. enterica serovar Infantis (SI) were evaluated. White Leghorn layer hens were immunized using whole cell of inactivated SI. Salmonella Infantis-specific antibody activities in sera and egg yolk were determined by ELISA. A total of 480 one-day-old male "Cobb 500" chicks were randomly divided into 8 groups, with 6 replications of 10 birds kept for 21 D. All birds from 7 challenged groups were orally inoculated with 1 mL of SI suspension (1 × 107 CFU/mL) at 3 and 4 D of age. Two groups were dietary supplemented with 5 g/kg immune powdered yolk or nonimmune powdered yolk. One group was dietary supplemented with 12.8 g/kg capsulated immune yolk (CIY). Two groups were given 8.3 mL/L of immune water-soluble yolk or nonimmune water-soluble yolk fraction in drinking water. In the antibiotic group, 1 mL/L Enrofloxacin 10% was added to drinking water. All supplements except for the antibiotic (on Day 4 for 10 D) were added on day one and continued during the experiment. Negative and positive control groups received no supplements. During the experiment, among the challenged groups, the minimum SI cecal colonization and the lowest isolation of SI from the liver (P < 0.01) was observed in the antibiotic group. Following antibiotic group, in the group receiving CIY, colonization of bacteria in ceca and liver was significantly reduced during the second and third weeks of the experiment (P < 0.01). According to the results, capsulated specific IgY has a beneficial effect in reducing the colonization of Salmonella under the conditions of this study in comparison with other forms of IgY antibody.

The effectiveness of a dietary direct-fed microbial and mannan oligosaccharide on ultrastructural changes of intestinal mucosa of turkey poults infected with Salmonella and Campylobacter.

Salmonella and Campylobacter are considered major public health burdens worldwide, and poultry are known to be one of the main reservoirs for these zoonotic pathogens. This study was conducted to evaluate the effect of a commercial probiotic or direct-fed microbial (DFM) Calsporin (CSP), and prebiotic or mannan oligosaccharide (MOS) (IMW50) on ultrastructural changes and the villous integrity of intestinal mucosa in turkey poults challenged with Salmonella and Campylobacter. A 21-day battery cage study was conducted using 4 dietary treatments including a basal diet (corn and soybean-based) nonsupplemented and uninfected as a negative control (NC); basal diet supplemented with 0.05% DFM (CSP); basal diet supplemented with 0.05% MOS (IMW50); and basal diet supplemented with 0.05% mixture of DFM and MOS at equal proportions. Female large white turkey poults aged 336 days were obtained from a local commercial hatchery and randomly distributed in electrically heated battery cages with 12 treatments of 4 replicates per treatment containing 7 poults per pen. The first 16 pens were not infected with bacteria, poults in pens 17-32 were orally challenged at day 7 with 105 cfu Salmonella Heidelberg, and the poults in pens 33-48 were orally challenged at day 7 with 105 cfu Campylobacter jejuni. Feed and water were provided ad libitum throughout the study. At day 21, ileal tissue samples from 1 bird per cage were collected for intestinal integrity and ultrastructural examination by scanning and electron microscopy. DFM and MOS supplementation was effective in both challenged and nonchallenged (not infected with Salmonella and Campylobacter) birds. Goblet cells and mucus were increased, with the presence of large numbers of segmented filamentous bacteria in DFM- and MOS-supplemented groups compared with birds in control treatments. The number and size of villi were reduced in poults exposed to Salmonella and Campylobacter. Results show that CSP and IMW50 provide protection of ileal mucosal integrity in poults exposed to Salmonella or Campylobacter.

Exploratory cohort study to determine if dry cow vaccination with a Salmonella Newport bacterin can protect dairy calves against oral Salmonella challenge.

BACKGROUND: Salmonellosis is a major cause of morbidity and mortality in neonatal calves, often occurring before preventative vaccines can be administered. HYPOTHESIS/OBJECTIVE: To evaluate the protective effect on calves of colostrum from cows vaccinated with a commercially available Salmonella Newport bacterin against a Salmonella Typhimurium challenge. ANIMALS: Twenty Holstein bull calves from a university dairy farm. METHODS: Nonrandomized placebo-controlled trial in which colostrum was harvested from 30 cows that received 2 doses of either Salmonella bacterin or saline before calving. Colostrum collected from each group was pooled and fed to 2 groups of 10 calves at birth. At approximately 2 weeks of age, calves were challenged with Salmonella Typhimurium. Clinical, hematologic, microbiological, and postmortem findings were compared between the 2 groups. RESULTS: No differences in mortality, clinical findings, hematology results, blood and fecal cultures, or necropsy findings between the 2 groups were observed. Vaccinated cows had higher colostral titers, and calves fed this colostrum had higher serum titers (mean difference, 0.429; mean [SE], 0.852 [0.02] for vaccinated versus 0.423 [0.02] for control calves). CONCLUSIONS AND CLINICAL IMPORTANCE: Transfer of colostral immunoglobulins from Salmonella enterica serotype Newport bacterin to neonatal calves was not sufficient to decrease mortality, clinical signs, sepsis, intestinal damage, or fecal shedding when exposed to a highly pathogenic Salmonella isolate. A large-scale randomized controlled clinical trial is needed to evaluate the efficacy of this bacterin when administered in the dry period for prevention of salmonellosis in neonatal calves.

Alginate-coated chitosan microparticles encapsulating an oral plasmid-cured live Salmonella enterica serovar Gallinarum vaccine cause a higher expression of interferon-gamma in chickens compared to the parenteral live vaccine.

Salmonella enterica serovar Gallinarum causes a disease in chickens known as fowl typhoid. Interferon-gamma (IFN-γ) has been shown to be crucial in eliminating salmonellosis infection because of its strong association with T-cell responses. This study was undertaken to compare the expression of IFN-γ in chickens generated by different vaccine formulations. Eighty one-day-old Lohmann layer chicks were divided into four groups of 20 birds each for the experiment. This comprised an unvaccinated negative control group (NEG), a group vaccinated with the live 9R vaccine by the injection route (SC), a group vaccinated with alginate-coated chitosan microparticles encapsulating live plasmid-cured S. Gallinarum strain 9 (PC) by the oral route, and a group vaccinated with a weak attenuated live S. Gallinarum strain 9 encapsulated in alginate-coated chitosan microparticles (VM) given orally. Vaccinations were done at 10 and 14 weeks of age followed by challenge at 16 weeks of age. IgG was measured using ELISA. qRT-PCR was used to compare the mRNA fold expression of IFN-γ in the PC, VM and SC groups using the unvaccinated/unchallenged group as the control. There were significant differences in the IgG levels between each vaccinated group and the unvaccinated group (P < 0.05) after booster vaccination and post-challenge. There was 100% protection of the birds in SC and VM groups, 80% protection in PC group and 0% protection in the NEG group. Using 2-ΔΔCT calculation, IFN-γ was more highly expressed in the PC group than in the SC group or VM group. In conclusion, the IFN-γ was more highly expressed in the PC group (though not significantly higher) compared to the SC and VM groups and this could be attributed to the alginate-coated chitosan microparticles which acted as an adjuvant.

The effect of some natural alternative to antibiotics on growth and changes in intestinal histology in broiler exposed to Salmonella challenge.

This study was conducted to find the effect of different feed additives on the production performance and intestinal histology in Salmonella challenged birds. A total of 600 day-old-broiler chicks (Ross 308) were assignment to 10 treatments. Each treatment was further divided into 10 replicates. The chicks were randomly divided into one of the following 10 treatments as follow: Negative control; positive control infected with Salmonella enterica subsp. typhimurium; T1, infected + avilamycin at the rate of 0.2 g/kg; T2, infected + probiotic having viable spores (2 × 107 CFU/g) of Bacillus subtilis (ATCC PTA-6737); T3, infected + Sanguinarine consisting of benzo phenanthridine alkaloids from Macleaya cordata; T4, B. subtilis (ATCC PTA-6737) + Sanguinarine; T5, infected + B. subtilis 500 g/T of feed (1.2 × 106 cfu/g); T6, prebiotic, Saccharomyces boulardii (1 × 108cfu/g); T7, infected + oregano at the rate of 1 g/kg; T8, infected + thermally processed clay calcium montmorillonite. The results showed that feed intake was significantly (P < 0.01) high in negative control and T2 compared to the positive control. Body weight gain was significantly (P < 0.01) higher in negative control and significantly (P < 0.05) low in T8. Feed conversion ratio was significantly (P < 0.05) high in negative control and significanlty (P < 0.05) high in T6. Similarly, PEF was also significantly (P < 0.05) high in negative control and significantly (P < 0.05) low in positive control and T8. Villus width was significantly (P < 0.05) high in negative control followed by T8. Dietary supplementation of different feed additives may be useful in broiler chicks challenged with Salmonella infection.

Effect of dietary canthaxanthin and iodine on the production performance and egg quality of laying hens.

In this study, we aimed to evaluate the effect of canthaxanthin (CX) and iodine (I) on the production of laying hens, on counteracting debilitation of the vitelline membrane, and on inhibiting Salmonella growth in eggs stored at 30°C. Three hundred hens were reared in cages. Birds were divided into six feeding groups (10 hens × 5 repetitions) that were administered 0, 3 or 6 ppm of CX and 1 or 10 ppm of I with their diets. Laying rate, egg weights, and feed conversion ratios were controlled. The quality of fresh eggs was assessed in wks 25-26, 48-50 and 62-63 of hens lives. An additional batch of eggs was incubated at the temperature of 30°C, and egg quality changes were monitored on days 3, 6 and 9 of storage. Additionally, eggs collected from four experimental groups of hens whose diets had been iodated with 1 or 10 ppm of I and supplemented with 0 or 6 ppm of CX were infected under laboratory conditions with Salmonella, and incubated for 5 and 10 d. The laying rate, egg weights, and feed conversion ratio were significantly improved. Dietary inclusion of CX contributed to a higher resistance of the vitelline membrane of egg yolks, but only for fresh eggs. Vitelline membrane degradation during egg storage at 30°C was significantly counteracted by dietary inclusion of I at a dose of 10 ppm. The same I dose resulted in the complete inhibition of Salmonella growth until day 10 of incubation, but exclusively for eggs collected from 40-week-old hens. Dietary supplementation with 10 ppm of I was found to impart high level of resistance to the vitelline membrane against the growth of Salmonella in case of eggs stored at 30°C; therefore, I was found to be more beneficial by ensuring longer preservation than that of CX. However, dietary supplementation with CX was found to increase the resistance of vitelline membrane in fresh eggs.

Effect of dietary fructooligosaccharide supplementation on internal organs Salmonella colonization, immune response, ileal morphology, and ileal immunohistochemistry in laying hens challenged with Salmonella enteritidis.

A study was conducted to evaluate the efficacy of fructooligosaccharides (FOS) in controlling the infection of Salmonella Enteritidis (SE) in White Leghorns. A total of 30 laying hens (white leghorns W-36) were challenged both orally and cloacally with approximately 108 colony-forming units of nalidxic acid resistant SE (SENAR) and divided into 3 treatments: 1) SENAR challenged + 0.0% FOS, 2) SENAR challenged + 0.5% FOS (Nutraflora), and 3) SENAR challenged + 1.0% FOS. SENAR recovery via fecal shedding was measured at 3- and 6-d post-infection (dpi), whereas in the ceca and internal organs, SENAR recovery was measured at 7-d post-infection. In the first experiment, there was a 1.0 log10 and a 1.3 log10 reduction in cecal SENAR by supplementation of FOS at 0.5 and 1.0%, respectively. In the second experiment, there was a 0.6 log10 and a 0.8 log10 reduction in cecal SENAR by supplementation of FOS at 0.5 and 1.0%, respectively. Fecal shedding was significantly lower in 1.0% FOS supplemented groups compared to SENAR challenge 0.0% FOS. There was no significant difference among the 3 treatments on SENAR recovery in liver with gall bladder and ovaries. However, the frequency of positive SENAR in the ovaries (10 to 40%) in SENAR challenge 0.0% FOS was significantly lower than liver with gall bladder (60 to 80%) in both experiments. There was a significant upregulation of toll-like receptor-4 in 1.0% FOS and interferon gamma in both 0.5 and 1.0% FOS. Histologic measurements of ileal villi height and crypt depth were similar across all treatments. Immunohistochemistry analyses of ileal samples showed that immunoglobulin A positive cells increased as FOS concentration increased reaching significance at 1.0% as well as altered cytokine gene expression in the ileum. Further, FOS supplementation also reduced cecal SENAR and feces SENAR levels. Collectively, the results suggest that dietary supplementation with FOS may impair SE pathogenesis while modulating humoral immunity within the gut-associated lymphoid tissue.

Defined and undefined commercial probiotics cultures in the prevention of Salmonella Enteritidis in broilers / Probióticos comerciais de culturas definidas e indefinidas na prevenção de Salmonella Enteritidis em frangos de corte

This study aimed to evaluate the efficacy of probiotics from different formations, defined and undefined cultures, applied in the control of Salmonella Enteritidis in broilers, identifying the compositions and states for which the probiotics are more effective. For that, 390 broilers were inoculated orally with 1.00 ml of Salmonella Enteritidis at a concentration of 1.2x109 CFU (Colony Forming Units). The experimental design used was randomized blocks with 5 treatments and 6 replications, totaling 30 boxes with 13 birds/box (13 birds/m2). The treatments were provided via drinking water 1 hour after inoculation, keeping a daily treatment of 12 hours with probiotics, for 3 consecutive days (birds at 1, 2 and 3 days of age). In general, the five treatments conducted were: T1 - Control without probiotic, T2 - Probiotic A (defined culture - lyophilized form, strain 7), T3 - Probiotic B (defined culture - lyophilized form, strain 11), T4 - Probiotic C (undefined culture liquid form), T5 - Probiotic D (undefined culture - liquid form). After treatments, performance was evaluated through average body weight, feed conversion and mortality counting. Microbiological analysis and Salmonella isolation were performed using MPN (Most Probable Number) and selective enrichment technique methods, respectively. Samples of ileum and liver pool, cecal tonsils, cecum, heart and spleen pool were collected at 5 and 31 days of age. No differences were observed on growth performance and isolation of Salmonella Enteritidis (p≥0.05). All probiotics applied were effective on reducing Salmonella Enteritidis colonization in the ileum, cecal tonsils, and cecum at 5 days of life. Probiotics T2 and T5 has shown effectiveness in reducing colonization at 31 days, being considered the most efficient on Salmonella Enteritidis control, for the intestines segments evaluated. It was not possible to affirm which probiotics formation, defined or undefined, is more efficient for Salmonella Enteritidis control.(AU)

O objetivo deste trabalho foi avaliar a eficácia dos probióticos de diferentes constituições: de culturas definidas e de culturas indefinidas no controle de Salmonella Enteritidis em frangos de corte, identificando qual a constituição e qual ou quais probióticos testados é mais eficaz. Foram inoculados 390 frangos de corte com 1ml de Salmonella Enteritidis, via oral, na concentração de 1,2 x 109 UFC (Unidades Formadoras de Colônia). O delineamento experimental utilizado foi o de blocos casualizados com 5 tratamentos e 6 repetições cada, totalizando 30 boxes com 13 aves/boxe (13 aves/m2). Os tratamentos foram fornecidos via água de bebida 1 hora após a inoculação, com 12 horas de tratamento com probióticos por dia, durante 3 dias consecutivos (1º, 2º e 3º dia de idade das aves). Os cinco tratamentos foram: T1 - Controle sem probiótico, T2 - Probiótico A (cultura definida - forma liofilizada, 7 cepas), T3 - Probiótico B (cultura definida - forma liofilizada, 11 cepas), T4 - Probiótico C (cultura indefinida - forma líquida), T5 - Probiótico D (cultura indefinida - forma liofilizada). O desempenho zootécnico foi avaliado usando o peso médio, a conversão alimentar e a mortalidade. Análises microbiológicas foram realizadas utilizando o método NMP (NMP/g)e isolamento de Salmonella através técnica de enriquecimento seletivo. Amostras de pool de íleo, tonsilas cecais e cecos e pool de fígado, coração e baço foram coletadas aos 5 dias e aos 31 dias de idade. Para desempenho zootécnico e isolamento de Salmonella Enteritidis não foram observadas diferenças (p≥0,05). Todos os probióticos utilizados foram eficazes na redução da colonização de Salmonella Enteritidis no íleo, tonsilas cecais e cecos aos 5 dias de idade e somente os probióticos do T2 (cultura definida) e T5 (cultura indefinida) reduziram a colonização aos 31 dias sendo considerados os mais eficazes no controle de Salmonella Enteritidis nestes segmentos intestinais avaliados. Não se pode afirmar quais das constituições de probióticos, culturas definidas ou indefinidas, são mais eficazes no controle de Salmonella Enteritidis.(AU)

The effect of refined functional carbohydrates from enzymatically hydrolyzed yeast on the transmission of environmental Salmonella Senftenberg among broilers and proliferation in broiler housing.

Hatching eggs collected from resident broiler breeders at 48 wk of age were used to produce male and female chicks that were assigned sex separately to 96 new litter pens and fed either a 0 or 50 g/MT RFC (refined functional carbohydrate feed additive derived from yeast) diet. There were 24 replicate pens of 12 broilers each per diet per sex. Feed intake and BW were determined at 14, 28, and 42 d of age. Litter was sampled by pen using sterile socks at 35 d and tested for Salmonella spp. using an enzyme linked fluorescence assay method. Salmonella spp. was isolated from 7 of 48 control-fed broiler pens but no RFC-fed pens (P ≤ 0.05). Thereafter, 48 males and 48 females were selected based on litter Salmonella presence and RFC treatment. The cecas of these broilers were aseptically excised after feed withdrawal and lairage and tested for presence of Salmonella spp. There were 18 of the 48 control-fed broilers confirmed positive from litter-positive pens but none from litter-negative pens fed RFC. The serovar of litter and cecal Salmonella isolates was Salmonella enterica subsp. enterica serovar Senftenberg (S. Senftenberg). Female broilers that were fed RFC exhibited greater BW at 28 d (P ≤ 0.05) and 42 d (P ≤ 0.05) while RFC-fed males exhibited improved feed efficiency during the 15-28 d period (P = 0.06). These data demonstrated that dietary RFC reduced the prevalence of Salmonella in the litter and ceca of broilers when fed continuously while not being detrimental to broiler live performance.