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Effect of Lactobacillus plantarum on intestinal microbial community composition and response to enterotoxigenic Escherichia coli challenge in weaning piglets
Abstract
Weaning is a critical period in a pig's life. Probiotics such as lactobacilli may prevent post-weaning diarrhoea but little knowledge yet exists on the effects of Lactobacillus plantarum in pigs. Therefore, we set up 2 experiments. In experiment 1, 176 piglets were divided into 5 treatment groups: 1) no probiotic (LP0), 2) 5×109cfu (total amount) before weaning on 25days of life (LP1), 3) 5×1010cfu before weaning (LP2), 4) 5×109cfu at weaning on 28days of life (LP3), and 5) 5×109cfu at weaning (LP4). On days 25, 28, 33 and 39 of life, 10–13 animals of each group were killed and DNA extracted from intestinal contents. Molecular microbiological analysis showed that L. plantarum significantly affected intestinal microbiota in groups LP3 and LP4 by increasing the abundance of butyrate producing bacteria in the colon and the ileal concentration of lactic acid. In experiment 2, 120 piglets were challenged with 3×109cfu Escherichia coli (O149:K91:F4ac) at weaning followed by of 3×109cfu or 3×1010cfu L. plantarum >2h later. No significant differences in ADG, ADFI, FCR and intestinal parameters were observed between treatments. L. plantarum administration at 3×1010cfu resulted in a significant reduction of diarrhoea incidence within 11days after the challenge. The studies show that a single administration of 3×1010cfu L. plantarum at weaning can affect intestinal microbial community composition in piglets and thereby promote intestinal health after enterotoxigenic E. coli challenge.
... Differences in diarrhea incidence were observed among the studies. Considering the positive control group of the different studies, it could be observed that ETEC F4 inoculation induced a diarrhea incidence reaching 40-50% at 3 d post-inoculum (dpi) [86], 5 dpi [117] and 7 dpi [12] while it reached 80% in the studies of Pan et al. [115] at 3 dpi. A reduction in diarrhea incidence has been observed within 11 dpi by Pieper et al. [117] and Kiers et al. [86] despite the difference in F4 ETEC dosages. ...
... Considering the positive control group of the different studies, it could be observed that ETEC F4 inoculation induced a diarrhea incidence reaching 40-50% at 3 d post-inoculum (dpi) [86], 5 dpi [117] and 7 dpi [12] while it reached 80% in the studies of Pan et al. [115] at 3 dpi. A reduction in diarrhea incidence has been observed within 11 dpi by Pieper et al. [117] and Kiers et al. [86] despite the difference in F4 ETEC dosages. ...
... Other studies have provided information only on total E. coli fecal shedding [101,107,117] or measuring the CFU at the level of the colon [110]. Since E. coli is considered an ubiquitary bacterium, its total increase cannot be directly associated with the increase in the pathogenic strain used for the challenge; therefore, the total increase in E. coli is not considered a precise indicator for claiming the success of the challenge protocol. ...
The enterotoxigenic Escherichia coli (ETEC) expressing F4 and F18 fimbriae are the two main pathogens associated with post-weaning diarrhea (PWD) in piglets. The growing global concern regarding antimicrobial resistance (AMR) has encouraged research into the development of nutritional and feeding strategies as well as vaccination protocols in order to counteract the PWD due to ETEC. A valid approach to researching effective strategies is to implement piglet in vivo challenge models with ETEC infection. Thus, the proper application and standardization of ETEC F4 and F18 challenge models represent an urgent priority. The current review provides an overview regarding the current piglet ETEC F4 and F18 challenge models; it highlights the key points for setting the challenge protocols and the most important indicators which should be included in research studies to verify the effectiveness of the ETEC challenge. Based on the current review, it is recommended that the setting of the model correctly assesses the choice and preconditioning of pigs, and the timing and dosage of the ETEC inoculation. Furthermore, the evaluation of the ETEC challenge response should include both clinical parameters (such as the occurrence of diarrhea, rectal temperature and bacterial fecal shedding) and biomarkers for the specific expression of ETEC F4/F18 (such as antibody production, specific F4/F18 immunoglobulins (Igs), ETEC F4/F18 fecal enumeration and analysis of the F4/F18 receptors expression in the intestinal brush borders). On the basis of the review, the piglets' response upon F4 or F18 inoculation differed in terms of the timing and intensity of the diarrhea development, on ETEC fecal shedding and in the piglets' immunological antibody response. This information was considered to be relevant to correctly define the experimental protocol, the data recording and the sample collections. Appropriate challenge settings and evaluation of the response parameters will allow future research studies to comply with the replacement, reduction and refinement (3R) approach, and to be able to evaluate the efficiency of a given feeding, nutritional or vaccination intervention in order to combat ETEC infection.
... A large proportion of lactose remains undigested in the small intestine and is simply fermented to lactic acid mainly by lactobacilli in the colon (Giang et al., 2010). Higher levels of dietary lactose in weaned pig cause a decrease in the cecum and colon pH, and a concomitant increase in volatile fatty acids (VFA) and lactobacilli (Pierce et al., 2006;Pieper et al., 2010). ...
... Given the reported anti-pathogenic competition effect of Lactobacillus spp. on specific pathogenic bacteria (Pieper et al., 2010), it is possible that providing lactose as a Lactobacillus spp. growth stimulator may affect commensal bacteria in the gut. ...
A 2 × 2 factorial arrangement was used to investigate the interactions between lactose levels (100 g/kg versus 200 g/kg) and Lactobacillus-based fermentation product (FP; 0 and 1 × 10¹¹ CFU Lactobacillus casei/kg) on weanling piglet performance and nutrient digestibility. Two hundred and forty weaned piglets (24 days old, 7.05 kg live weight) were blocked on the basis of live weight and assigned to one of four dietary treatments with six replicates and 10 piglets per replicate in two phases (phase 1, from d 1 to 14; phase 2, from d 14 to 28). Volatile fatty acid concentrations and bacterial counts were performed in ileal, cecal, and colonic contents. In phase Ⅰ, ADG was increased (P < 0.01) in pigs fed FP. The digestibility of DM and GE were greater (P < 0.01) in pigs offered high lactose level. The interactions between lactose level and FP were significant for the concentration of ileal acetate (P < 0.05) and propionate (P < 0.01). The concentration of propionate in the cecum and colon, as well as butyrate in the ileum, were greater (P < 0.05) in high lactose treatment. Dietary supplementation of FP decreased acetate level in the cecum. The emission of total organic carbon and ammonia in pigs feces were decreased (P < 0.01) in both high lactose and FP-supplemented diets. The interactions between lactose and FP were significant (P < 0.05) for the population of Salmonella spp. in the ileum. The pH of colon digesta was lower (P < 0.05) in pigs offered high lactose level. The abundance of Lactobacillus spp. was increased (P < 0.05) only in the cecum digesta in pigs offered high lactose diet. In phase Ⅱ, there was a significant improvement in the feed:gain in pigs fed the diet with high lactose content. The overall result showed that ADG and ADFI were increased in pigs in FP treatment. The greater digestibility of DM was observed in pigs offered FP. The concentration of butyric acid in the colon was increased in pigs fed FP. The supplementation of FP decreased ileal and cecal Escherichia coli. This study demonstrates that dietary FP improved the growth performance and DM digestibility of weanling pigs. When the dietary FP, and the lactose level were combined there was no evidence of an interaction on growth performance. However, both lactose and FP decreased the emissions of total organic carbon and ammonium.
... Regarding the incidence of diarrhea, this was reduced marginally by the inclusion of the probiotic in the diet (P ϭ 0.09); although we were not able to demonstrate any reduction in the counts of E. coli K88, we did observe an increase in the number of lactobacilli in the colon. In this regard, Pieper et al. (37) reported that L. plantarum stimulated the beneficial microbiota and lactic acid production in the ileum of piglets challenged with ETEC K88. Our results support these previous findings. ...
... Together with a possible control of proteolytic activity, the beneficial effects of L. plantarum could also be due to other mechanisms, including a trend toward higher production of total SCFA in the ileum (P ϭ 0.06) and in the colon (P ϭ 0.08), with higher percentages of butyrate at both sites (P ϭ 0.07). Previous results with nonchallenged piglets also showed the ability of L. plantarum to increase butyrate pro- duction (17), likely due to promotion of butyrate-producing bacteria (37). Regarding a possible effect of the probiotic on the modulation of the immune response, we found a lower number of intraepithelial lymphocytes (IEL) and a reduction in the plasma TNF-␣ level in the piglets fed L. plantarum. ...
The potential of a prebiotic oligosaccharide lactulose, a probiotic strain of Lactobacillus plantarum, or their synbiotic combination to control postweaning colibacillosis in pigs was evaluated using an enterotoxigenic Escherichia coli (ETEC) K88 oral challenge. Seventy-two weanlings were fed four diets: a control diet (CTR), that diet supplemented with L. plantarum (2 × 1010 CFU · day−1) (LPN), that diet supplemented with 10 g · kg−1 lactulose (LAC), or a combination of the two treatments (SYN). After 7 days, the pigs were orally challenged. Six pigs per
treatment were euthanized on days 6 and 10 postchallenge (PC). Inclusion of lactulose improved the average daily gain (ADG)
(P < 0.05) and increased lactobacilli (P < 0.05) and the percentage of butyric acid (P < 0.02) in the colon. An increase in the ileum villous height (P < 0.05) and a reduction of the pig major acute-phase protein (Pig-MAP) in serum (P < 0.01) were observed also. The inclusion of the probiotic increased numbers of L. plantarum bacteria in the ileum and colon (P < 0.05) and in the total lactobacilli in the colon and showed a trend to reduce diarrhea (P = 0.09). The concentrations of ammonia in ileal and colonic digesta were decreased (P < 0.05), and the villous height (P < 0.01) and number of ileal goblet cells (P < 0.05) increased, at day 10 PC. A decrease in plasmatic tumor necrosis factor alpha (TNF-α) (P < 0.01) was also seen. The positive effects of the two additives were combined in the SYN treatment, resulting in a complementary
synbiotic with potential to be used to control postweaning colibacillosis.
... Probiotics maintain the balance of the intestinal ecosystem by promoting beneficial bacteria and inhibiting harmful bacteria and are closely related to health conditions [42]. Previous studies have shown that L. plantarum (3 × 10 10 ) can greatly reduce the incidence of diarrhea in weaned piglets [43]. ...
A total of 180, 4-week-old crossbred weaning piglets ((Yorkshire × Landrace) × Duroc; 6.67 ± 1.40 kg) were used in a 42 day experiment to evaluate the effect of dietary probiotics (Lactobacillus plantarum BG0001) on growth performance, nutrient digestibility, blood profile, fecal microbiota, and noxious gas emission. All pigs were randomly allotted to one of four treatment diets in a completely randomized block design. Each treatment had nine replicates with five pigs/pen (mixed sex) Designated dietary treatments were as: (1) basal diet (NC), (2) NC + 0.2% antibiotics (chlortetracycline) (PC), (3) NC + 0.1% L. plantarum BG0001 (Lactobacillus plantarum BG0001) (NC1), (4) NC + 0.2% L. plantarum BG0001 (NC2). On d 42, BW and G:F were lower (p < 0.05) in pigs fed NC diet compared with PC diet and probiotic diets. Throughout this experiment, the average daily gain increased (p < 0.05) in pigs when fed with PC and probiotic diets than the NC diet. The average daily feed intake was higher (p < 0.05) in pigs fed PC diet during day 0–7 and 22–42, and probiotic diets during day 0–7 compared with NC diet, respectively. The Lactobacillus count was increased and Escherichia coli count was decreased (p < 0.05) in the fecal microbiota of pigs fed probiotic diets, and E. coli were decreased (p < 0.05) when fed a PC diet compared with the NC diet on day 21. Moreover, the apparent total tract nutrient digestibility, blood profile, and the concentration of noxious gas emission had no negative effects by the probiotic treatments. In conclusion, dietary supplementation with L. plantarum BG0001 significantly improved the growth performance, increased fecal Lactobacillus, and decreased E. coli counts in weaning pigs.
... The L. plantarum has antagonistic potential against intestinal pathogens through competitive exclusion and production of lactic acid and bactericidal compounds (Kaushik et al., 2009). These properties make L. plantarum a promising probiotic feed additive, and several previous studies demonstrated that the use of L. plantarum in weaning pigs could prevent the diarrhea induced by Escherichia coli K88 challenge (Lee et al., 2012;Yang et al., 2014), improve the intestinal microbial balance (Pieper et al., 2010), and enhance the small intestinal villus height (Suo et al., 2012). But, these benefits of probiotics usage in pigs are not always consistent and the efficacy of probiotics is strain-dependent (Zimmermann et al., 2016). ...
A total of 60 weaned pigs with initial body weight (BW) of 8.51 ± 0.42 kg (28 d of age) were randomly divided into 2 groups of 30 each consisted of 6 pens with 2 gilts and 3 borrows and supplemented (treatment) 5.3×108 cfu/kg Lactobacillus plantarum GB805 in addition to basal diet offered during d 0 to 14 and d 15 to 42 (control). During the total trial period or different phases of trial, pigs fed L. plantarum diet had a higher (P less than 0.05) ADG, ADFI and feed efficiency. At the end of experiment, dietary L. plantarum supplementation improved (P less than 0.05) the apparent total tract digestibility of dry matter, nitrogen and the fecal Lactobacillus populations (P less than 0.05) while the fecal E.coli populations were decreased (P less than 0.05). In conclusion, dietary supplementation of L. plantarum GB805 had positive influence on growth rate, nutrient digestibility and gut microbial balance and its supplementation recommended to weaning pigs.
... Further analysis on the microbiota in the gastrointestinal tract treated by lactobacilli and antibiotics by PCR-DGGE was investigated for the comparison Values are means ± S.D, n = 3. a, b, c Mean in a same column with different superscripts differ significantly (P < 0.05) The results suggested that the mechanisms of antibiotics and lactobacilli on regulating intestinal microbiota were through different ways and lactobacilli contributed to comparatively complex bacterial community. Some similar results were also shown in other reports [30,31]. The results in Table 4 and Fig. 2 showed the discrepancy in similarities between lactobacilli and antibiotics treatments tended to decrease from d 14 to d 28. ...
Background:
The beneficial effects of Lactobacillus probiotics in animal production are often strain-related. Different strains from the same species may exert different weight-gain effect on hosts in vivo. Most lactobacilli are selected based on their in vitro activities, and their metabolism and regulation on the intestine based on strain-related characters are largely unexplored. The objective of the present study was to study the in vivo effects of the three lactobacilli on growth performance and to compare the differential effects of the strains on the faecal microbiota and ileum mucosa proteomics of piglets.
Methods:
Three hundred and sixty piglets were assigned to one of four treatments, which included an antibiotics-treated control and three experimental groups supplemented with the three lactobacilli, L. salivarius G1-1, L. reuteri G8-5 and L. reuteri G22-2, respectively. Piglets were weighed and the feed intake was recorded to compare the growth performance. The faecal lactobacilli and coliform was quantified using quantitative PCR and the faecal microbiota was profiled by denaturing gradient gel electrophoresis (DGGE). The proteomic approach was applied to compare the differential expression of proteins in the ileum mucosa.
Results:
No statistical difference was found among the three Lactobacillus-treated groups in animal growth performance compared with the antibiotics-treated group (P > 0.05). Supplementation of lactobacilli in diets significantly increased the relative 16S rRNA gene copies of Lactobacillus genus on both d 14 and d 28 (P < 0.05)., and the bacterial community profiles based on DGGE from the lactobacilli-treated groups were distinctly different from the antibiotics-treated group (P < 0.05). The ileum mucosa of piglets responded to all Lactobacillus supplementation by producing more newly expressed proteins and the identified proteins were all associated with the functions beneficial for stabilization of cell structure. Besides, some other up-regulated and down-regulated proteins in different Lactobacillus-treated groups showed the expression of proteins were partly strain-related.
Conclusions:
All the three lactobacilli in this study show comparable effects to antibiotics on piglets growth performance. The three lactobacilli were found able to modify intestinal microbiota and mucosa proteomics. The regulation of protein expression in the intestinal mucosa are partly associated with the strains administrated in feed.
... Probiotics can be used to prevent and treat microbial imbalance by altering intestinal populations, epithelial lining, and the gut-associated lymphoid tissues (Metzler et al., 2005). Feeding Lactobacillus derived from the pig intestine as probiotics reduced the abundance of Enterobacteriaceae including pathogenic E. coli, reduced incidence of diarrhea (Huang et al., 2004;De Angelis et al., 2007;Pieper et al., 2010), enhanced immune response during infection (Naqid et al., 2015), and increased weight gain (Konstantinov et al., 2008). Furthermore, treatment of suckling pigs with Lactobacillus reuteri can protect by reducing intestinal pH through lactic acid production via Bifidobacterium spp., subsequently reducing abundance of E. coli (Hou et al., 2015). ...
• The gut microbial ecosystem is fundamental in proper nutritional, physiological, and immunological functions of the pig. However, composition and function of a healthy microbial ecosystem have yet to be qualitatively and quantitatively defined to be used as a tool to maximize animal health and performance.
• As efforts are made to reduce antibiotic use in swine production, the gut microbiota needs to be recognized for its capacity to enhance disease resistance.
• Increasing diet complexity, by including cereal grains high in fermentable carbohydrates, is a sustainable option to increase microbial diversity and beneficial microbes, help prevent incidence of post-weaning diarrhea, and decrease sub-therapeutic antibiotic use.
• Although currently limited by regulatory issues, the introduction of microbial communities that have evolved to protect the pig may increase diversity of the gut microbial ecosystem and provide further protection.
... A recent study by Pieper et al. (2010) investigated the timing of probiotic (Lactobacillus plantarum) administration, as the current practise of applying several administrations per week is not practical. They found that administration of 5 · 10 9 cfu L. plantarum once at weaning increased ileal concentration of lactic acid and butyrate-producing bacteria in the colon compared with pigs administered on 3 days before weaning. ...
For the last several decades, antimicrobial compounds have been used to promote piglet growth at weaning through the prevention of subclinical and clinical disease. There are, however, increasing concerns in relation to the development of antibiotic-resistant bacterial strains and the potential of these and associated resistance genes to impact on human health. As a consequence, European Union (EU) banned the use of antibiotics as growth promoters in swine and livestock production on 1 January 2006. Furthermore, minerals such as zinc (Zn) and copper (Cu) are not feasible alternatives/replacements to antibiotics because their excretion is a possible threat to the environment. Consequently, there is a need to develop feeding programs to serve as a means for controlling problems associated with the weaning transition without using antimicrobial compounds. This review, therefore, is focused on some of nutritional strategies that are known to improve structure and function of gastrointestinal tract and (or) promote post-weaning growth with special emphasis on probiotics, prebiotics, organic acids, trace minerals and dietary protein source and level.
Conditions affecting the gastrointestinal tract occur in pigs of all ages. Enteric diseases substantially compromise production efficiencies and profitability of pig production globally. Different forms of fiber in the diet can influence the composition and metabolic activity of the large intestinal microflora in pigs. Alternatives to antibiotic inclusion in weaner diets include the use of organic acids such as potassium diformate. Phytogenic feed additives comprise a wide variety of herbs, spices, and products derived from these materials that have been shown to have antimicrobial properties in vitro. Liquid feeding can improve the feed intake, growth, feed conversion, and health of weaned pigs. Oral rehydration fluids are used in piglets with acute diarrhea especially during outbreaks of enterotoxigenic E. coli and rotavirus infections. Gastric over‐distension can occur in adult pigs, especially in sows, but the cause is uncertain. The peritoneal cavity is intrinsically involved with the health and normal function of the digestive system.
Effects of probiotics on the intestinal microbiota of foals are yet insufficiently studied. The aim of this study was to investigate whether supplementation of Lactobacillus rhamnosus (DSM 7133) and Enterococcus faecium (DSM 7134) influences the bacterial composition of the faecal microbiota of foals. A total of 34 newborn foals were randomly assigned to the placebo group (PG, n = 16) and the treatment group (TG, n = 18). From day 1 to day 14 of life, foals orally received 3 ml of either a probiotic preparation (1.05 × 109 CFU E. faecium and 4.50 × 108 CFU L. rhamnosus) or placebo (carrier) once a day. Faeces were collected directly from the rectum immediately after birth (meconium) and at day 14 and day 56 of life. Samples of 12 foals per group were selected for microbiological analysis. DNA was extracted and used for polymerase chain reaction–denaturing gradient gel electrophoresis (PCR‐DGGE) and quantitative PCR. No DNA or amplicons were obtained from meconium. There were no differences in richness of bands and Shannon index of diversity regarding the Clostridium cluster XIVa between groups. Cluster analysis and principal coordinate analysis of DGGE data showed a clear effect of age. Band‐based similarity of bacterial clusters (Dice coefficient) decreased from day 14 to day 56 of life (p < 0.001) in PG foals only resulting in lower similarity in PG versus TG foals when 2 month old (p < 0.01). Five of thirty re‐amplified bands were identified on species level. Others were assigned either to family (mainly Lachnospiraceae) or genus level (Akkermansia). The bands related to Akkermansia muciniphila or Akkermansia spp. appeared almost in all DGGE profiles. Two‐week supplementation of the probiotic preparation to foals had no significant impact on the composition of the faecal microbiota but it appears to have prevented the reduction of bacterial similarity between 2 and 8 weeks of age observed in not treated foals.
In this study, we evaluated the probiotic properties of two strains Lactobacillus reuteri ZLR003 and Lactobacillus salivarius ZLS006. The two strains displayed tolerance of acid and heat, and demonstrated antimicrobial ability in vitro. Furthermore, their potential functions in vivo were also tested. A total of 120 crossbred (Landrace × Large White) growing pigs were divided into three groups: a control diet, the same diet supplemented with L. reuteri ZLR003 (2.0 × 10⁹ cfu/kg of diet) or L. salivarius ZLS006 (3.50 × 10⁹ cfu/kg of diet). The results showed that the average daily gain and feed conversion ratio were significantly improved in L. reuteri ZLR003- (1-5 weeks and 1-9 weeks) (P < 0.05) and L. salivarius ZLS006-treated pigs (1-5 weeks, 6-9 weeks and 1-9 weeks) (P < 0.05) compared with the control group. Dietary supplementation with L. salivarius ZLS006 increased the apparent digestibility of nitrogen at Week 9 (P < 0.05). The faecal Lactobacillus populations increased at the end of experiment, and the Escherichia coli and Staphylococcus aureus in faeces decreased in the two Lactobacillus treatments compared with the control at Week 5 (P < 0.05) and Week 9 (P < 0.05), respectively. Furthermore, the total cholesterol, alanine transferase, aspartate transferase, blood urea nitrogen and haptoglobin levels in serum were significantly decreased following L. reuteri ZLR003 and L. salivarius ZLS006 treatments (P < 0.05). In conclusion, these data suggest that the two Lactobacillus strains may be promising candidates for probiotic products in growing-finishing pigs.
Prebiotics and probiotics have attracted considerable interest as alternatives or replacements for growth-promoting antibiotics and/or some heavy metals in diets for pigs, particularly in the post-weaning period where the newly weaned pig is subject to considerable challenges in its new environment. This chapter briefly reviews the microbiota of the gastrointestinal tract of the young pig and the important role it plays in the early stages of life. The chapter then defines probiotics, prebiotics and synbiotics, in addition to reviewing the research conducted on the topic, including a case study where a probiotic product (Peribios™) has been used commercially to modulate the production around parturition. Finally, it looks ahead for possible future trends and offers suggestions on where to look for more information on the topic.
Probiotics are live microorganisms that can confer a health benefit on the host, and amongst various mechanisms probiotics are believed to exert their effects by production of antimicrobial substances, competition with pathogens for adhesion sites and nutrients, enhancement of mucosal barrier integrity and immune modulation. Through these activities probiotics can support three core benefits for the host: supporting a healthy gut microbiota, a healthy digestive tract and a healthy immune system. More recently, the concept of combining probiotics and prebiotics, i.e. synbiotics, for the beneficial effect on gut health of pigs has attracted major interest, and examples of probiotic and prebiotic benefits for pigs are pathogen inhibition and immunomodulation. Yet, it remains to be defined in pigs, what exactly is a healthy gut. Because of the high level of variability in growth and feed conversion between individual pigs in commercial production systems, measuring the impact of probiotics on gut health defined by improvements in overall productivity requires large experiments. For this reason, many studies have concentrated on measuring the effects of the feed additives on proxies of gut health including many immunological measures, in more controlled experiments. With the major focus of studying the balance between gut microbiology, immunology and physiology, and the potential for prevention of intestinal disorders in pigs, we therefore performed a literature review of the immunomodulatory effects of probiotics, either alone or in combination with prebiotics, based on in vivo, in vitro and ex vivo porcine experiments. A consistent number of studies showed the potential capacity in terms of immunomodulatory activities of these feed additives in pigs, but contrasting results can also be obtained from the literature. Reasons for this are not clear but could be related to differences with respect to the probiotic strain used, experimental settings, diets, initial microbiota colonization, administration route, time and frequency of administration of the probiotic strain and sampling for analysis. Hence, the use of proxy measurements of enteric health based on observable immunological parameters presents significant problems at the moment, and cannot be considered robust, reliable predictors of the probiotic activity in vivo, in relation to pig gut health. In conclusion, more detailed understanding of how to select and interpret these proxy measurements will be necessary in order to allow a more rational prediction of the effect of specific probiotic interventions in the future.
Lactobacillus plantarum FS5-5—a new isolate from agricultural soybean paste—shows good growth in an environment with 12 % (w/v) NaCl. To understand the potential relationship between regulatory systems and its growth under different salt concentrations, the expression of genes encoding enzymes involved in five regulatory systems was determined by quantitative real-time polymerase chain reaction (qPCR). The results showed that the optimal growth of this strain relied on the cooperative action of different regulatory systems, with each system playing an important role in L. plantarum FS5-5 in adapting to salt stress. Interestingly, most of the genes showed higher expression under higher concentrations of NaCl, suggesting that L. plantarum FS5-5 uses its regulatory systems preferentially to sustain its growth. In addition, the expression change of a gene encoding glyceraldehyde-3-phosphate dehydrogenase (gapB) was not significant under different salt concentrations, indicating that it may be used as a housekeeping gene in the qPCR experiment on L. plantarum after exposure to salt stress. This study provided a global view of the effect of NaCl on the ability of L. plantarum FS5-5 to resist salt stress and may help us to develop strategies to improve the robustness of industrial production.
The effect of lactic acid bacteria (LAB) on silage storage and livestock production has caught the increasing attention of many scientists. The exploration of LAB with a high-performance in silage making is noteworthy for future research and is extremely important for developing safe livestock production and for increasing self-supplying feed. LAB not only influences the large intestine by affecting the intestinal flora but also by affecting other organs via the modulation of immunological parameters and intestinal permeability or via the production of bioactive or regulatory metabolites. This chapter first discusses the use of LAB in animal feeding. The protective effects of LAB that can inhibit food-borne pathogens in live animals before slaughter have been described. LAB are capable of producing inhibitory substances, other than organic acids, that have inhibitory activities against different microorganisms. However, not all LAB will reduce food-borne pathogens in farm animals; therefore, the careful selection of strains to be administered under appropriate conditions is important. In addition, effects of LAB on feed preparation and animal production are described and reviewed.
The effect of lactic acid bacteria (LAB) on silage storage and livestock production has caught the increasing attention of many scientists. The exploration of LAB with a high-performance in silage making is noteworthy for future research and is extremely important for developing safe livestock production and for increasing self-supplying feed. LAB not only influences the large intestine by affecting the intestinal flora but also by affecting other organs via the modulation of immunological parameters and intestinal permeability or via the production of bioactive or regulatory metabolites. This chapter first discusses the use of LAB in animal feeding. The protective effects of LAB that can inhibit food-borne pathogens in live animals before slaughter have been described. LAB are capable of producing inhibitory substances, other than organic acids, that have inhibitory activities against different microorganisms. However, not all LAB will reduce food-borne pathogens in farm animals; therefore, the careful selection of strains to be administered under appropriate conditions is important. In addition, effects of LAB on feed preparation and animal production are described and reviewed.
There exists little doubt that the Earth's biodiversity is declining. The
Nature Conservancy, for example, has documented that one-third of the plant
and animal species in the United States are now at risk of extinction. The
problem is a monumental one, and forces us to consider in depth how we expect
ecosystems, which ultimately are our life-support systems, to respond to reductions
in diversity. This issue — commonly referred to as the diversity–stability
debate — is the subject of this review, which synthesizes historical
ideas with recent advances. Both theory and empirical evidence agree that
we should expect declines in diversity to accelerate the simplification of
ecological communities.
Lactobacillus plantarum is a versatile lactic acid bacterium that is encountered in a range of environmental niches, has a proven ability to survive gastric transit, and can colonize the intestinal tract of human and other mammals. Several studies describe the effects of L. plantarum consumption on human physiology. The availability of the complete genome sequence of L. plantarum WCFS1 makes it a suitable model to explore the molecular mechanisms underlying the targeted intestinal properties of this species. An increasing number of studies address the development of L. plantarum into an ingestible living vaccine. Furthermore, studies are emerging to determine the activity of L. plantarum in the human intestinal tract. This review discusses the studies of the safety and survival of L. plantarum in the human intestinal tract, the effects of this bacterium on the host and it provides an overview of the molecular studies addressing the activity of L. plantarum in the human gut environment.
This experiment was aimed at comparing the intestinal microbial community composition in pigs fed hulled common barley supplemented with isolated barley mixed-linked beta-glucan, four hulless barley varieties and breeding lines with mixed-linked beta-glucan contents ranging from 41 to 84 g kg(-1) and different amylose/amylopectin ratios as well as two oat varieties. Seventy-two weaned piglets were allocated to one of nine diets composed of 81.5% cereal, 6% whey, 9% soy protein isolate and 3.5% minerals. After 15 days, pigs were sacrificed and ileum and colon contents were collected for quantitative real-time PCR (qPCR) and denaturing gradient gel electrophoresis to evaluate microbial communities. Shifts in intestinal microbial communities were observed with the hulless barley cultivars with a normal to high beta-glucan content and from normal starch toward either high-amylopectin or high-amylose starch. These hulless barleys had the lowest (P<0.05) microbial diversity, whereas oats had intermediate diversity compared with low-beta-glucan hulless cultivars and hulled varieties. Furthermore, hulless varieties favoured xylan- and beta-glucan-degrading bacteria whereas mixed-linked beta-glucan-supplemented hulled barley favoured lactobacilli. Numbers of lactobacilli decreased in the ileum of pigs fed hulless/high mixed-linked beta-glucan barley-based diets. Thus, cultivar differences in both the form and the quantity of carbohydrates affect gut microbiota in pigs, which provides information for future feeding strategies.
The microbial community in the guts of mammals is often seen as an important potential target in therapeutic and preventive interventions. The aim of the present study was to determine whether enterotoxigenic Escherichia coli (ETEC) F4 infection in young animals might be counteracted by a probiotic treatment with Lactobacillus sobrius DSM 16698. The experiment was conducted in three randomized consecutive replications, each consisting of 16 piglets, and including a control group and an L. sobrius fed group, both experimentally challenged with ETEC. During the entire trial, the animals' health status, body weight, and microbial parameters were monitored periodically. Probiotic supplementation containing L. sobrius significantly reduced the levels of ETEC in the ileum when fed directly to piglets after weaning. In contrast, the number of days when the piglets had an increased faecal water content was significantly higher in the probiotic group. Nevertheless, an improved daily weight gain was also observed in the animals that received probiotic L. sobrius relative to the control fed group. The data indicate that L. sobrius may be effective in the reduction of the E. coli F4 colonization and may improve the weight gain of infected piglets.
Interactions between the intestinal microflora, diet and diarrhoea, and their influences on piglet health in the immediate post-weaning period
- Hopwood