Efficacy of Two Probiotic Products Fed Daily to Reduce Clostridium perfringens-Based Adverse Health and Performance Effects in Dairy Calves

Clostridium perfringens is a spore-forming, anaerobic bacterium which produces toxins and exoenzymes that cause disease in calves, especially necro-hemorrhagic enteritis-associated diarrhea often resulting in death. Clostridium infections are currently being treated with antibiotics, but even with the prudent administration of antibiotics, there are significant rates of recurrence. Probiotics, an alternative to antibiotics, are commonly employed to prevent clostridial infections. The objectives of our study were to demonstrate that two commercially available products, when used as daily, direct-fed microbials, are effective in reducing adverse effects of an experimentally induced C. perfringens infection in dairy calves. We conducted a single site efficacy study with masking using a randomized design comprising 10 calves allocated to 3 treatment groups (probiotic 1, probiotic 2, and control). The procedures such as general health scores, body weight, blood samples, and fecal sample collections were done followed by experimental challenge of calves with C. perfringens. Daily feeding of L. animalis LA51 and P. freudenreichii PF24 without or with Bacillus lichenformis CH200 and Bacillus subtilis CH201, before, during and after an oral challenge of C. perfringens significantly reduced the incidence and severity of diarrhea while improving general impression and appearance scores of calves. Most notably, survival of calves in the two probiotic-fed groups was significantly higher than for control calves and further substantiates the potential economic and health benefits of feeding effective probiotics.

Probiotics as Alternatives to Antibiotics for the Prevention and Control of Necrotic Enteritis in Chickens

Necrotic enteritis (NE) in poultry is an economically important disease caused by Clostridium perfringens type A bacteria. A global trend on restricting the use of antibiotics as feed supplements in food animal production has caused a spike in the NE incidences in chickens, particularly in broiler populations. Amongst several non-antibiotic strategies for NE control tried so far, probiotics seem to offer promising avenues. The current review focuses on studies that have evaluated probiotic effects on C. perfringens growth and NE development. Several probiotic species, including Lactobacillus, Enterococcus, Bacillus, and Bacteroides bacteria as well as some yeast species have been tested in chickens against C. perfringens and NE development. These findings have shown to improve bird performance, reduce C. perfringens colonization and NE-associated pathology. The underlying probiotic mechanisms of NE control suggest that probiotics can help maintain a healthy gut microbial balance by modifying its composition, improve mucosal integrity by upregulating expression of tight-junction proteins, and modulate immune responses by downregulating expression of inflammatory cytokines. Collectively, these studies indicate that probiotics can offer a promising platform for NE control and that more investigations are needed to study whether these experimental probiotics can effectively prevent NE in commercial poultry operational settings.

Alternatives to antibiotics for organic poultry production: types, modes of action and impacts on bird's health and production

The poultry industry contributes significantly to bridging the nutritional gap in many countries because of its meat and eggs products rich in protein and valuable nutrients at a cost less than other animal meat sources. The natural antibiotics alternatives including probiotics, prebiotics, symbiotics, organic acids, essential oils, enzymes, immunostimulants, and phytogenic (phytobiotic) including herbs, botanicals, essential oils, and oleoresins are the most common feed additives that acquire popularity in poultry industry following the ban of antibiotic growth promoters (AGPs). They are commonly used worldwide because of their unique properties and positive impact on poultry production. They can be easily mixed with other feed ingredients, have no tissue residues, improve feed intake, feed gain, feed conversion rate, improve bird immunity, improve digestion, increase nutrients availability as well as absorbability, have antimicrobial effects, do not affect carcass characters, decrease the usage of antibiotics, acts as antioxidants, anti-inflammatory, compete for stress factors and provide healthy organic products for human consumption. Therefore, the current review focuses on a comprehensive description of different natural antibiotic growth promoters’ alternatives, the mode of their action, and their impacts on poultry production.

Effect of Lactobacillus Species Probiotics on Growth Performance of Dual-Purpose Chicken

Introduction

In-feed probiotics are becoming attractive alternatives to antibiotics in the poultry industry due to the ever-growing strict prohibitions on antibiotic growth promoters (AGP) in animal production.

Methods

The study was conducted to investigate the effects of Lactobacillus paracaseis sparacasei and Lactobacillus rhamnosus on the growth performance of 120 day-olds randomly selected Sasso dual-purpose chicken. They were divided into four groups with two replicates per group and 15 chicks per replicate. The treatments were T₁ (control), T₂ (supplement diet with 4g probiotic), T₃ (supplement diet with 2g probiotic), T₄ (supplement diet with 1g probiotic). The experimental feeding trials were conducted after two weeks adaptation period.

Results

The present findings revealed that the chickens supplemented with Lactobacillus species probiotics during the first week of age have shown higher body weight than control (p < 0.05). The feed intake of week one of T₂ and T₃ were significantly higher (p< 0.05) than the T₁ (control). However, there was no significant difference (p> 0.05) in feed intake in the 2^nd, 3^rd, 4^th, and 5^{t h} weeks of all treatment groups. The present result showed that there was a significant body weight gain (p< 0.05) in all probiotic fed groups than the control group. The highest body weight gain was observed in chickens found in the T4 treatment group. Whereas the body weight gains significantly higher and improved the feed conversion (p<0.05) in the T₂ and T₄ than the T₁ (control). However, the feed conversion ratio was significantly influenced by probiotic inclusion in T₃ as compared to the control group.

Conclusion

Overall, the results suggest that Lactobacillus paracaseis sparacasei and Lactobacillus rhamnosus have a positive effect on the growth performance of broilers.

Dietary inclusion of multispecies probiotics to reduce the severity of post-weaning diarrhea caused by Escherichia coli F18+ in pigs

This study was aimed to determine the efficacy of multispecies probiotics in reducing the severity of post-weaning diarrhea caused by enterotoxigenic Escherichia coli (ETEC) F18⁺ on newly weaned pigs. Thirty-two pigs (16 barrows and 16 gilts, BW = 6.99 ± 0.33 kg) at 21 d of age were individually allotted in a randomized complete block design with 2 × 2 factorial arrangement of treatments. Pigs were selected from sows not infected previously and not vaccinated against ETEC. Pigs were fed experimental diets for 25 d based on 10 d phase 1 and 15 d phase 2. The factors were ETEC challenge (oral inoculation of saline solution or E. coli F18⁺ at 2 × 10⁹ CFU) and probiotics (none or multispecies probiotics 0.15% and 0.10% for phase 1 and 2, respectively). Body weight and feed intake were measured on d 5, 9, 13, 19, and 25. Fecal scores were measured daily. Blood samples were taken on d 19 and 24. On d 25, all pigs were euthanized to obtain samples of digesta, intestinal tissues, and spleen. The tumor necrosis factor alpha (TNFα), malondialdehyde (MDA), peptide YY (PYY), and neuropeptide Y (NPY) were measured in serum and intestinal tissue. Data were analyzed using the MIXED procedure of SAS. The fecal score of pigs was increased (P < 0.05) by ETEC challenge at the post–challenge period. The ETEC challenge decreased (P < 0.05) jejunal villus height and crypt depth, tended to increase (P = 0.056) jejunal TNFα, increased (P < 0.05) ileal crypt depth, and decreased (P < 0.05) serum NPY. The probiotics decreased (P < 0.05) serum TNFα, tended to reduce (P = 0.064) jejunal MDA, tended to increase (P = 0.092) serum PYY, and increased (P < 0.05) jejunal villus height, and especially villus height-to-crypt depth ratio in challenged pigs. Growth performance of pigs were not affected by ETEC challenge, whereas the probiotics increased (P < 0.05) ADG and ADFI and tended to increase (P = 0.069) G:F ratio. In conclusion, ETEC F18⁺ challenge caused diarrhea, intestinal inflammation and morphological damages without affecting the growth performance. The multispecies probiotics enhanced growth performance by reducing intestinal inflammation, oxidative stress, morphological damages.

Impact of a Bacillus Direct-Fed Microbial on Growth Performance, Intestinal Barrier Integrity, Necrotic Enteritis Lesions, and Ileal Microbiota in Broiler Chickens Using a Laboratory Challenge Model

Decreases in the use of antibiotics and anticoccidials in the poultry industry have risen the appearance of necrotic enteritis (NE). The purpose of this study was to evaluate the effect of a Bacillus direct-fed microbial (DFM) on growth performance, intestinal integrity, NE lesions and ileal microbiota using a previously established NE-challenged model. At day-of-hatch, chicks were randomly assigned to three different groups: Negative control (NC), Positive control (PC) challenged with Salmonella Typhimurium (day 1), Eimeria maxima (EM, day 13) and Clostridium perfringens (CP, day 18-19), and Bacillus-DFM group (DFM) challenged as the PC. Body weight (BW) and body weight gain (BWG) were measured weekly. Total feed intake (FI) and feed conversion ratio (FCR) were evaluated at day 21. Liver samples were collected to assess bacterial translocation and blood samples were used to measure superoxide dismutase (SOD) and fluorescein isothiocyanate-dextran (FITC-d). Intestinal contents were obtained for determination of total IgA and microbiota analysis. NE lesion scores (LS) were performed at day 21. Chickens consuming the DFM significantly improved BW and had a numerically more efficient FCR compared to PC at day 21. Additionally, there were no significant differences in FCR between the DFM group and NC. Furthermore, the DFM group showed significant reductions in LS, IgA and FITC-d levels compared to the PC. However, there were no significant differences in SOD between the groups. The microbiota analysis indicated that the phylum Proteobacteria was significantly reduced in the DFM group in comparison to PC. At the genus level, Clostridium, Turicibacter, Enterococcus, and Streptococcus were reduced, whereas, Lactobacillus and Bacillus were increased in the DFM group as compared to PC (p < 0.05). Likewise, the DFM significantly reduced CP as compared to PC. In contrary, no significant differences were observed in bacterial composition between NC vs. DFM. In addition, beta diversity showed significant differences in the microbial community structure between NC vs. PC, and PC vs. DFM. These results suggest that the dietary inclusion of a selected DFM could mitigate the complex negative impacts caused by NE possibly through mechanism(s) that might involve modulation of the gut microbiota.

Valeric acid glyceride esters in feed promote broiler performance and reduce the incidence of necrotic enteritis

Valeric acid is a C5 fatty acid, naturally produced in low concentrations by specific members of the microbiota of the lower intestinal tract. Effects of valeric acid on intestinal health have been poorly investigated. Valeric acid derivatives can be produced as glyceride esters and added to broiler feed. In the current study, experiments were carried out to evaluate the effect of valeric acid glycerides (GVA) on growth performance, on the morphology of the small intestinal mucosa and on protection against necrotic enteritis. In a first feeding trial, Ross-308 chicks were randomly divided into 2 dietary treatment groups and fed either a non-supplemented diet or a diet supplemented with GVA (1.5 g/kg). In the GVA supplemented group, the feed conversion ratio was significantly decreased during the entire trial period (D1-37). In a second trial, gut wall morphology was evaluated. In broilers fed a GVA-containing diet at 5 g/kg, the villus height/crypt depth ratio in the jejunum was significantly increased (P ≤ 0.05), and the crypt depth was significantly decreased at 28 d. In a third trial, immunohistochemistry showed that the density of glucagon-like peptide-2 immunoreactive cells in jejunal and ileal villi from broilers supplemented with GVA (5 g/kg) was significantly increased (P ≤ 0.05) on d 10. In a necrotic enteritis challenge model, a significant reduction of the number of birds with necrotic lesions was found at d 21, using in-feed supplementation of low and high regimen of GVA. These data show that GVA supplementation to broiler feed can decrease the feed conversion, positively affect the morphology of the small intestinal mucosa, increase the density of glucagon-like peptide-2 producing enteroendocrine cells, and reduce the incidence of necrotic enteritis, making GVA a valuable candidate feed additive for broilers.

Effects of direct-fed microorganisms and enzyme blend co-administration on intestinal bacteria in broilers fed diets with or without antibiotics

Direct-fed microorganisms (DFM) and exogenous enzymes have been demonstrated to improve growth performance in poultry and are potentially important alternatives to antibiotic growth promoters (AGP). We investigated the administration of a feed additive composed of a DFM product containing spores of 3 Bacillus amyloliquefaciens strains and an enzyme blend of endo-xylanase, α-amylase, and serine-protease in diets with or without sub-therapeutic antibiotics in broiler chickens over a 42-d growth period. Evaluation of growth performance determined feed efficiency of broiler chickens which were administered the feed additive was comparable to those fed a diet containing AGPs. Characterization of the gastrointestinal microbiota using culture-dependent methods determined administration of the feed additive increased counts of total Lactic Acid Bacteria (LAB) relative to a negative control and reduced Clostridium perfringens to levels similar to antibiotic administration. Additionally, greater counts of total LAB were observed to be significantly associated with reduced feed conversion ratio, whereas greater counts of C. perfringens were observed to be significantly associated with increased feed conversion ratio. Our results suggest the co-administration of DFMs and exogenous enzymes may be an important component of antibiotic free poultry production programs and LAB and C. perfringens may be important targets in the development of alternatives to AGPs in poultry production.

In ovo supplementation of probiotics and its effects on performance and immune-related gene expression in broiler chicks

Probiotics are live, nonpathogenic microorganisms known to have a positive effect on the host by improving the natural balance of gut microbiota. The objective of this study was to determine the effects of administering probiotics (Primalac W/S) in ovo on hatchability, early post-hatch performance, and intestinal immune-related gene expression of broiler chicks. At embryonic day eighteen, 360 Cobb 500 eggs were injected with sterile water (sham), 1 × 105, 1 × 106, or 1 × 107 (P1, P2, and P3 respectively) probiotic bacteria. Another 90 eggs remained non-injected to serve as a negative control. Measurements and tissue samples were taken on day of hatch (DOH) and days 4, 6, 8, 15, and 22. No significant differences were seen among groups for hatchability, feed intake, feed conversion ratios, or mortality. Body weight of P2 was significantly greater than that of the negative control, sham and P1 on d 4, and that of the negative control and P1 on d 6. A similar pattern was observed for BW gain (BWG) from DOH to d 4. Real-time PCR was used to investigate the expression of immune-related genes in the ileum and cecal tonsils. Other than an initial upregulation of inducible nitric oxide synthase on DOH, in ovo probiotic supplementation was associated with downregulated expression of Toll-like receptors-2 and -4, inducible nitric oxide synthase, trefoil factor-2, mucin-2, interferon-γ, and interleukins-4 and -13 in both the ileum and cecal tonsils, though expression patterns differed based on treatment, tissue, and time point evaluated. Taken together, these results indicate that in ovo supplementation of the probiotic product Primalac does not impact hatchability, can improve performance during the first week post-hatch, and is capable of modulating gene expression in the ileum and cecal tonsils.

Two Lactobacillus Species Inhibit the Growth and α-Toxin Production of Clostridium perfringens and Induced Proinflammatory Factors in Chicken Intestinal Epithelial Cells in Vitro

Clostridium perfringens is the causative pathogen of avian necrotic enteritis. Lactobacillus spp. are well-characterized probiotics with anti-microbial and immune-modulatory activities. In the present study, we investigated the effects of L. acidophilus and L. fermentum on the growth, α-toxin production and inflammatory responses of C. perfringens. In in vitro culture experiments, both lactobacilli inhibited the growth of C. perfringens (P < 0.01), accompanied with a decrease in pH (P < 0.01). Supernatants from lactobacilli cultures also suppressed the growth of C. perfringens during 24 h of incubation (P < 0.01), but this inhibitory effect disappeared after 48 h. Both lactobacilli decreased the α-toxin production of C. perfringens (P < 0.01) without influencing its biomass, and even degraded the established α-toxin (P < 0.01). Lower environmental pH reduced the α-toxin production as well (P < 0.01). Preincubation with L. acidophilus decreased the attachment of C. perfringens to cells (P < 0.01) with the cell cytotoxicity being unaffected. Both lactobacilli pretreatment reduced the up-regulation of proinflammatory factors, peptidoglycan (PGN) receptors and nuclear factor kappa B (NF-κB) p65 in C. perfringens-challenged chicken intestinal epithelial cells (P < 0.05). In conclusion, L. acidophilus and L. fermentum inhibited the pathological effects of C. perfringens in vitro conditions.

Effects of in ovo supplementation of probiotics on performance and immunocompetence of broiler chicks to an Eimeria challenge

Coccidiosis is regarded as the parasitic disease with the greatest economic impact on the poultry industry due to reduced performance and increased mortality. A study was conducted to investigate the effects of in ovo administration of probiotics on hatchability, performance, immune organ weights, and lesion scores in broiler chicks during a mixed Eimeria infection. At embryonic day 18, 210 eggs were injected with either sterile water or 1×106 cfu probiotic bacteria. On day 3 post-hatch, half of the chicks from each treatment group were challenged with a mixed inoculum of Eimeria acervulina, Eimeria maxima and Eimeria tenella. Measurements and tissue samples were taken on day of hatch (DOH) and days 3, 9 and 15. On day 9, 24 birds per treatment were scored for intestinal Eimeria lesions. No differences were seen among groups for hatchability as well as for body weight (BW), BW gain (BWG), or immune organ weights prior to the Eimeria challenge. On day 9, the non-challenged birds with probiotic supplementation had higher BW and BWG than the non-supplemented controls while no differences were seen among the challenged groups. On day 15, probiotic supplemented birds had improved BW compared to the non-supplemented birds as well as increased BWG from day 9 to 15. Bursa weight was not affected by treatment at any time point while spleen weight was greater in supplemented birds on day 15. Birds receiving the probiotic had significantly lower mortality than non-treated birds. Additionally, gross lesion severity was reduced due to probiotic supplementation in all intestinal segments evaluated. These results suggest that in ovo supplementation of probiotics may improve early performance and provide protection against a mixed Eimeria infection.

Combination of probiotics and coccidiosis vaccine enhances protection against an Eimeria challenge

Coccidiosis is endemic in the commercial broiler industry capable of inflicting devastating economic losses to poultry operations. Vaccines are relatively effective in controlling the disease; their efficacy could potentially be improved with concurrent use of probiotics as evaluated in this study using an Eimeria challenge. Day of hatch 400 Cobb-500 male broilers were assigned to one of four treatment groups including control (CON), vaccine-only gel application (VNC), probiotic-only gel application (NPC), and vaccine-plus-probiotic gel application (VPC). Birds were placed in floor pens (6 replicate pens/treatment, 16-17 birds/pen). NPC and VPC birds received the probiotics in the water on days 2-4, 8, 14-20, 22, 29, and 34-36. On day 15, birds were mildly challenged with 0.5 mL of a mixed oral inoculum of Eimeria sp. prepared with the coccidiosis vaccine at 10× the vaccination dose. Performance measurements were recorded on first day and weekly afterwards, and lesion scores were evaluated 6 days post-challenge. Overall, the probiotics and coccidiosis vaccine resulted in an enhanced protective effect against the challenge, with VPC birds exhibiting lower lesion scores in the duodenum than VNC or NPC birds. Birds in the VPC treatment also demonstrated higher weight gains during days 1-15, days 7-15, and days 21-28 when compared to the VNC birds. These results suggest that the combination of probiotics and coccidiosis vaccines could enhance performance and provide an additional protective effect against a mixed Eimeria challenge.

Can Bacteriotherapy Using Commercially Available Probiotics, Prebiotics, and Organic Acids Ameliorate the Symptoms Associated With Runting-Stunting Syndrome in Broiler Chickens?

Runting-stunting syndrome (RSS) in poultry has been known for more than 40 years, but the precise etiology remains unknown and a licensed vaccine is consequently not currently available. In order to mitigate the symptoms associated with RSS, a series of experiments was performed to investigate whether a combined bacteriotherapeutic treatment consisting of probiotics, prebiotics, and organic acids could influence the outcome of this disease. Initially two groups of commercial broiler chickens were either left uninoculated or inoculated with filtrate from homogenized intestines of RSS-affected broiler chickens. One group from each of these two challenge groups was treated, with a bacteriotherapeutic regimen. After 12 days chickens were euthanatized, the body weight was measured, and duodenal lesions were enumerated. Five consecutive broiler chicken flocks were then raised either on litter from RSS-affected birds or on fresh wood shavings. Treatment had no beneficial effect on the number and severity of intestinal lesions. There appeared to be a significant build-up of RSS agent(s) in poultry litter, with each consecutive flock placement, independent of bacteriotherapeutic treatment, as more individuals exhibited intestinal lesions on built-up litter in RSS-affected houses (28.9% vs. 44%). While treatment did not appear to consistently reduce intestinal lesions, it did significantly improve the mean body weights (P<0.05) and uniformity of 12-day-old chickens placed on reused litter in houses in which RSS-infected birds were previously raised. A combination of litter management and bacteriotherapy may be needed to ameliorate the adverse effects of RSS on intestinal health and body weight in broiler chickens.

Immunomodulatory role of probiotics in poultry and potential in ovo application

Recently, there has been an increasing debate regarding the use of sub-therapeutic antibiotics in animal feed. This stems from worries that this practice may result in microbial resistance to human antibiotics employed in treating infections, thus causing a human health concern. Due to this tension, the poultry industry is under mounting pressure to reduce the use of these agents as feed additives and alternative control methods have taken the forefront in the research community. Investigators are searching for the latest alternative that will protect flocks from disease, while not hindering performance or negatively impacting profit margins. Probiotic supplementation is one option currently being explored as a means of improving performance and reducing the amount and severity of enteric diseases in poultry, and subsequent contamination of poultry products for human consumption. Probiotics are live, nonpathogenic microorganisms known to have a positive effect on the host by beneficially modifying gut microbiota and modulating the immune system. This review will discuss the role of probiotics in poultry, including their effects on performance, immune response and host defence against disease. Also addressed will be the recent applications of supplementing probiotics in ovo as an innovative means to administer such additives to promote early colonisation of beneficial bacteria.

A review on prebiotics and probiotics for the control of dysbiosis: present status and future perspectives

Dysbiosis or dysbacteriosis is defined as a shift in the intestinal microbiota composition resulting in an imbalance between beneficial and harmful bacteria. Since the ban on the use of growth-promoting antibiotics in animal feed in the EU, dysbiosis has emerged as a major problem in intensive animal production. Prebiotics and probiotics are currently under investigation as possible alternatives to growth-promoting antibiotics, as their mode of action is thought to be based largely on a modulation of the composition and function of the intestinal microbiota. In this review, we analyse the currently available data from both animal and human nutrition that document the potential and limitations of prebiotics and probiotics for the control of dysbiosis. An impressive number of empirical feeding trials have been carried out in healthy animals, yielding sometimes contradictory results. More in-depth studies have revealed the complexity of the interactions taking place in the lower intestinal tract, thus illustrating that pre- and probiotics cannot be a simple replacement for growth-promoting antibiotics. Although there are indications that the strategic use of pre- and probiotics can provide major benefits, there is still a lack of basic knowledge on the delicate interactions between the microbiota, the host and the feed components, which hampers the widespread use of these valuable feed additives.

Effects of probiotics and application methods on performance and response of broiler chickens to an Eimeria challenge

Coccidiosis is an inherent risk in the commercial broiler industry and inflicts devastating economic losses to poultry operations. Probiotics may provide a potential alternative to the prophylactic use of anticoccidials in commercial production. This study evaluated the effects of probiotic applications (feed and water) on bird performance and resistance to a mixed Eimeria infection in commercial broilers. On day of hatch, 1,008 commercial male broilers (Cobb 500) were assigned to 1 of 6 treatments (8 replicate floor pens; 21 birds/pen), including noninfected negative control (NEG), Eimeria-infected positive control (POS), anticoccidial control (0.01% salinomycin, SAL), intermittent high-dose water-applied probiotic (WPI), continuous low-dose water-applied probiotic (WPC), and feed-supplemented probiotic (FSP). On d 15, all birds except those in NEG were challenged with a mixed inoculum of Eimeria acervulina, Eimeria maxima, and Eimeria tenella. Measurements were taken on d 7, 15, 21, 28, 35, and 42. Fecal samples were collected from d 20 to 24 for oocyst counts, and lesion scores were evaluated on d 21. Data were analyzed using the Fit Model platform in JMP Pro 10.0 (SAS Institute Inc.). Differences in experimental treatments were tested using Tukey's honestly significant difference following ANOVA with significance reported at P ≤ 0.05. Overall, NEG birds outperformed all other groups. For performance, the probiotic groups were comparable with the SAL-treated birds, except during the 6 d immediately following the Eimeria species challenge, where the SAL birds exhibited better performance. The WPC birds had lower duodenal and jejunal lesion scores, indicating a healthier intestine and enhanced resistance to Eimeria species compared with POS. Birds in the WPI treatment shed fewer oocysts in the feces, although this was not a trend for all of the probiotic treatment groups. The results of this study suggest probiotic supplementation without anticoccidials can enhance performance and help alleviate the negative effects of a mixed Eimeria infection.

Effects of Clostridium butyricum on growth performance, immune function, and cecal microflora in broiler chickens challenged with Escherichia coli K88

This study was conducted to investigate the effects of Clostridium butyricumon growth performance, immune function, and cecal microflora in broiler chickens challenged with Escherichia coli K88. Three hundred sixty 1-d-old broiler chickens were randomly divided into 4 treatments: negative control (NC) birds were fed a basal diet and not challenged with E. coli K88; positive control (PC) birds were fed a basal diet and challenged with E. coli K88; C. butyricum treatment (CB) birds were fed a diet containing 2 × 10(7) cfu C. butyricum/kg of diet and challenged with E. coli K88; and colistin sulfate treatment (CS) birds were fed a diet containing 20 mg of colistin sulfate/kg of diet and challenged with E. coli K88. Birds fed CB had greater (P < 0.05) BW than the PC birds from 3 to 21 d postchallenge. Birds fed CB had greater (P < 0.05) serum IgA and IgY at 14 d postchallenge, greater (P < 0.05) serum IgM at 21 d postchallenge, and greater (P < 0.05) mucosal secreted IgA at 3 and 7 d postchallenge than the PC birds. Birds fed CB had greater concentrations of serum complement component 3 at 14 d postchallenge, and greater (P < 0.05) concentrations of serum complement component 4 at 3, 7, and 14 d postchallenge than the PC birds. Birds in the CS or CB treatments had less cecal E. coli population at 3, 7, and 21 d postchallenge, and less cecal Clostridium perfringens counts at 21 d postchallenge compared with the PC birds. The CB treatment increased (P < 0.05) the population of cecal Lactobacillus at 3 d postchallenge and the number of cecal Bifidobacterium at 3, 14, and 21 d postchallenge in comparison with the PC treatment. The results indicate that dietary supplementation of CB promotes growth performance, improves immune function, and benefits the cecal microflora in Escherichia coli K88-challenged chickens.

Modern approaches in probiotics research to control foodborne pathogens

Foodborne illness is a serious public health concern. There are over 200 known microbial, chemical, and physical agents that are known to cause foodborne illness. Efforts are made for improved detection, control and prevention of foodborne pathogen in food, and pathogen associated diseases in the host. Several commonly used approaches to control foodborne pathogens include antibiotics, natural antimicrobials, bacteriophages, bacteriocins, ionizing radiations, and heat. In addition, probiotics offer a potential intervention strategy for the prevention and control of foodborne infections. This review focuses on the use of probiotics and bioengineered probiotics to control foodborne pathogens, their antimicrobial actions, and their delivery strategies. Although probiotics have been demonstrated to be effective in antagonizing foodborne pathogens, challenges exist in the characterization and elucidation of underlying molecular mechanisms of action and in the development of potential delivery strategies that could maintain the viability and functionality of the probiotic in the target organ.