Post-weaning Diarrhoea In Piglets Research Articles

Polymorphism of M307 of the FUT1 Gene and Its Relationship with Some Immune Indexes in Sutai Pigs (Duroc × Meishan)

The alpha (1,2)fucosyltransferase (FUT1) gene has been identified as a candidate gene for controlling the expression of the enterotoxigenic Escherichia coli (ETEC) F18 receptor. Polymorphisms were detected at the M307 position in FUT1 of a breeding base population of Sutai pigs and their correlations to immune parameters analyzed. After digestion by Hin6I, three genotypes were identified at M307, AA (frequency 0.235), AG (0.609), and GG (0.156), with significant deviation from Hardy-Weinberg equilibrium (P < 0.01). The hemoglobin and white blood cell count of the AA genotype pigs were significantly higher than those of AG and GG pigs (P < 0.05). The results indicated that AA pigs not only are resistant to edema disease and post-weaning diarrhea in piglets but also have relatively strong resistance to disease in general.

CDNA microarray on differently expressed genes in duodenum in porcine sensitive or resistant to &lt;I&gt;Escherichia coli&lt;/I&gt; F18

Based on the paired full-sib individuals selected from the established resource populations of Sutai pig that were characterized as resistant or sensitive to ETEC F18, Agilent double labeled cDNA microarray was used to identify the gene expression profiles in duodenum on purpose of investigating the genes related to Escherichia coli F18 receptor, which may cause edema disease and post-weaning diarrhea in piglets, as well as exploring the molecular mechanism about the differences involved in two different lineages. The results showed that thirteen differently expressed genes were found in one matched group including sensitive ones with GG genotype comparing with resistant ones with AA genotype at a two-fold filter, where there were 6 up-regulated genes and 7 down-regulated genes. In the other matched group composed of sensitive ones with AG genotype, 4 up-regulated genes and 2 down-regulated genes, 6 in total were screened out. GO analy-sis revealed that the differently expressed genes participated in many biological processes, such as immune response, ex-tracellular region, bacterial binding, response to external stimulus and so on. Meanwhile, these genes were mainly related to the Glycan Biosynthesis and Metabolism and Immune System pathways. Actually, the roles that they may play in edema disease and post-weaning diarrhea need further study and verification.

Experimental infection of weaned piglets with enterotoxigenic Escherichia coli O149:F4

EnterotoxigenicEscherichia coliis an important enteric pathogen causing post-weaning diarrhoea in piglets. Enterotoxins ofE. coliinduce the release of fluid into the intestines without apparent inflammation. Some serotypes ofE. coli, especially O149:F4 can often be identified in association with haemorrhagic gastroenteritis. In this study we infected the weaned piglets (n = 53) by oral administration of enterotoxigenicE. coliO149:F4 strains isolated from piglets suffering from haemorrhagic gastroenteritis. The clinical course of infection and shedding of the challengeE. colistrain in the faeces of infected piglets was monitored for 14 days. The challenge strain soon outnumbered the otherE. colitypes in the intestines of most piglets. Diarrhoea developed in the majority of piglets and its severity varied. Severe diarrhoea was observed in 10% of the piglets but only one piglet died due to dehydration. No inflammatory lesions were detected in the intestines of the dead piglet and the other euthanized piglets. We assume that development of haemorrhagic gastroenteritis depends on the involvement of other factors that need to be identified.E. coliO149:F4 are only one of the causative factors of haemorrhagic gastroenteritis in piglets after weaning.

Bacterial Pericarditis due to Providencia stuartii

A 58-year-old man was admitted for relapsing pericarditis. His past medical history included a transient ischemic attack when he was 47 years old, radical right nephrectomy for neoplasia 8 years earlier, and hypertension. One year earlier, a diagnosis of pleuropericarditis was made in another hospital. The patient was febrile and complained of chest pain; an echocardiogram showed thickening of parietal pericardium, hyperechoic matter on visceral pericardium, and the presence of pericardial and pleural effusion, without hemodynamic impairment. Concomitantly, the patient had a dental abscess; cultures from this abscess were negative during antibiotic therapy. He was treated empirically with piperacillin/tazobactam for 15 days and then with amoxicillin/clavulanate for ≈1 month and …

Effects of dietary protein level and zinc oxide supplementation on the incidence of post-weaning diarrhoea in weaner pigs challenged with an enterotoxigenic strain of Escherichia coli

The interactive effects of dietary protein level, zinc oxide (ZnO) supplementation and experimental infection with enterotoxigenic E. coli (ETEC) on the incidence of post-weaning diarrhoea (PWD) and indices of protein fermentation were examined. Ninety-six, individually housed 21-day-old pigs were used in a split plot experiment, with the whole plot being challenge or no challenge with ETEC and the dietary treatments used as subplots and arranged in a completely randomised 2 × 2 factorial design, with the factors being (i) 2 dietary protein levels [251 g/kg (high) vs. 192 g/kg (low) crude protein] and (ii) addition or no addition of 2500 ppm ZnO. Between days 1 and 14 after weaning, ETEC infection increased faecal consistency (FC; looser faeces) but only in pigs fed the high protein diet (P < 0.05) or without ZnO (P < 0.1). Pigs fed a high protein diet without ZnO showed more loose faeces (higher FC) compared to pigs fed either a high protein diet with ZnO supplementation or pigs fed lower protein diets without and with ZnO supplementation (P < 0.05). Feeding either a low protein diet or ZnO decreased (P < 0.05) PWD. Feeding a low protein diet decreased (P < 0.001) plasma urea nitrogen (PUN) and faecal NH 3-N contents. There were no 2- or 3-way interactions (P > 0.05) between the independent variables for PWD, PUN and faecal NH 3-N. The results indicate that feeding a low protein diet supplemented with amino acids or adding ZnO to either low or high protein diets could be used as dietary strategies to reduce PWD in piglets.

Conformation Change in a Self-recognizing Autotransporter Modulates Bacterial Cell-Cell Interaction

Bacteria mostly live as multicellular communities, although they are unicellular organisms, yet the mechanisms that tie individual bacteria together are often poorly understood. The adhesin involved in diffuse adherence (AIDA-I) is an adhesin of diarrheagenic Escherichia coli strains. AIDA-I also mediates bacterial auto-aggregation and biofilm formation and thus could be important for the organization of communities of pathogens. Using purified protein and whole bacteria, we provide direct evidence that AIDA-I promotes auto-aggregation by interacting with itself. Using various biophysical and biochemical techniques, we observed a conformational change in the protein during AIDA-AIDA interactions, strengthening the notion that this is a highly specific interaction. The self-association of AIDA-I is of high affinity but can be modulated by sodium chloride. We observe that a bile salt, sodium deoxycholate, also prevents AIDA-I oligomerization and bacterial auto-aggregation. Thus, we propose that AIDA-I, and most likely other similar autotransporters such as antigen 43 (Ag43) and TibA, organize bacterial communities of pathogens through a self-recognition mechanism that is sensitive to the environment. This could permit bacteria to switch between multicellular and unicellular lifestyles to complete their infection.

Evaluation of Lactobacillus rhamnosus GG using an Escherichia coli K88 model of piglet diarrhoea: Effects on diarrhoea incidence, faecal microflora and immune responses

Probiotic bacterium Lactobacillus rhamnosus GG (LGG) has been demonstrated to adhere to pig intestinal mucus, and is able to displace and inhibit pathogens, including Escherichia coli (E. coli), in vitro. However, currently there are few data concerning the effects of LGG on piglet health. The objectives of this study were to assess the effectiveness of LGG in reducing the incidence and severity of post-weaning diarrhoea in piglets, and to investigate its mechanisms of action. Eighteen weaned barrows were allocated to nonchallenged control (NCN), challenged control (CCN) and LGG treatment (LGG) groups. Diarrhoea incidence was significantly lower in group LGG than group CCN after E. coli challenge. Faecal coliform bacteria counts were significantly increased, while lactobacilli and bifidobacteria counts were decreased, in group CCN compared with the other groups after challenge. In the jejunum and ileum, secretory immunoglobin A (SIgA) concentrations were significantly higher in group LGG than in group CCN. In group LGG, administration of short-term LGG before E. coli infection attenuated the elevation of serum IL-6 induced by E. coli. Significantly higher concentrations of TNF-alpha were observed in group LGG than NCN and CCN at 6h. IL-1beta concentrations in group NCN were significantly higher than LGG at 6h and higher than CCN at 24h. In conclusion, LGG was effective in ameliorating diarrhoea in post-weaning piglets induced by E. coli K88, possibly via modulation of intestinal microflora, enhancement of intestinal antibody defence, and regulation of production of systemic inflammatory cytokines.

Cytokine mRNA expression in porcine cell lines stimulated by enterotoxigenic Escherichia coli

Enterotoxigenic Escherichia coli (ETEC) is an extracellular bacterium that causes post-weaning diarrhoea (PWD) in piglets with different severity of clinical signs. The pathogenesis of ETEC is ascribed to the effect of enterotoxins. ETEC colonizes ileum and probably can penetrate the epithelium and stimulate macrophages. The aim of study was to examine whether there is any difference in cytokine response in vitro produced by two porcine cell lines, intestinal epithelial cell line (IPI-2I) and macrophage cell line (3D4/31) after stimulation with different serotypes of ETEC associated with different clinical course of PWD in piglets. Three serotypes, O149:K88 (F4), O147:F18 and O8:K88, were used. We observed that all the used serotypes were unable to induce IL-8 and TNF-α mRNA expression in IPI-2I cell line as measured by the real-time RT-PCR. In 3D4/31 cell line, we detected differences in cytokine response among the used serotypes. The highest IL-8 and TNF-α mRNA expression in 3D4/31 was detected after stimulation with serotype O149:K88 frequently associated with hemorrhagic gastroenteritis.

Dietary specific antibodies in spray-dried immune plasma prevent enterotoxigenic Escherichia coli F4 (ETEC) post weaning diarrhoea in piglets

In order to establish the mechanism of spray dried plasma powder (SDPP) in improving pig health and performance, a diet containing either 8% SDPP, spray dried immune plasma powder (SDIPP), or control protein (soybean and whey) ration was fed to piglets in an experimental model of enterotoxigenic Escherichia coli F4 (ETEC) post-weaning diarrhoea (PWD). SDIPP was obtained from pigs immunized with a vaccine containing ETEC fimbrial subunit F4 and heat-labile toxin (LT), and SDPP from non-immunized controls. Average daily growth (ADG) was determined, and daily samples of rectal faeces were assessed for diarrhoea (as percentage of dry matter), and ETEC excretion (in CFU/g). SDPP and SDIPP significantly ( p < 0.05) reduced diarrhoea, and SDIPP significantly reduced ETEC excretion. ADG was not significantly ( p > 0.05) affected. After the experiment, 30% of piglets tested F4 receptor positive (F4R+). A significant correlation between F4R status and morbidity was found. In F4R+ animals, SDIPP significantly improved diarrhoea and ADG, and decreased ETEC excretion, and SDPP significantly improved diarrhoea and ADG. Surprisingly, SDPP reduced diarrhoea in F4R+ animals without significant reduction of ETEC excretion, which is most likely related to the presence of anti-LT antibodies in SDPP. The results show that oral protection against ETEC by SDPP is attributable to spontaneous antibodies, in this case anti-LT antibodies. Furthermore, the results indicate that the combination of anti-LT and anti-F4 antibodies as in SDIPP is most effective in ETEC prevention. Finally, the F4R distribution in the herd should be taken into account to correctly assess efficacy.

Increasing diet viscosity using carboxymethylcellulose in weaned piglets stimulates protein digestibility

Abstract Ileal indigestible protein may be an important factor for the occurrence of post weaning diarrhoea in piglets. Depending on the quantity of indigested protein, an imbalance in the microbial community can occur, resulting in an overgrowth of pathogens. Diet viscosity may influence nutrient digestibility and substrate availability for microbial growth. Therefore, we examined the effect of dietary viscosity in piglet nutrition. Carboxymethylcellulose (CMC) was added as a model substance in order to increase diet viscosity. The effect of 1% supplemented CMC on nutrient digestibility, morphological and physiological parameters was measured in piglets 3 weeks post weaning at 26 days of age. The main effects of inclusion of CMC were: – A 10% slower gastric emptying rate ( P = 0.18). – An increased protein hydrolysis in the gastric fraction, measured as increased nitrogen concentration in the liquid phase of gastric contents (26% in control vs. 34% in experimental group; P = 0.13). – An increased production of the protein hydrolysing enzyme amino-peptidase from 359 U/g protein for the control diet to 516 U/g protein for the experimental diet ( P – A numerical increase in apparent ileal protein digestibility by 6% from 75.2% to 79.5% ( P = 0.22) and a significant increase in faecal protein digestibility by 5% ( P = 0.044). These results indicate that an optimized diet viscosity might be one factor exerting a beneficial influence on protein digestibility. We hypothesize that the effect of diet viscosity on gastric emptying rate is the major factor.

Organic acids, prebiotics and protein level as dietary tools to control the weaning transition and reduce post-weaning diarrhoea in piglets.

Abstract The most effective way to control post-weaning diarrhoea (PWD) in piglets remains the use of prophylactic and for therapeutic levels of antibiotics. However, increasing concerns about the transfer of antibiotic-resistant bacteria to humans via the use of antibiotic growth promoters (AGP) in animals have led to the ban in the European Union of all AGPs in pig diets from 1 January 2006. Consequently, it is important to develop ways of controlling the weaning transition in piglets without the use of antibiotic feed additives. The scope of this review is an examination of the adaptation of the gastrointestinal tract to weaning and the mechanisms of PWD. Furthermore, the addition of organic acids, prebiotics and probiotics as feed additives as well as dietary carbohydrate and protein modulation to minimize PWD will be discussed. Based on the available literature, organic acids can increase post-weaning performance significantly even though it is not possible at times to recognize the most effective dosage, acid or combination of acids. In some cases, prebiotics can increase the numbers of possible beneficial bacteria such as Lactobacillus spp. and Bifidobacterium spp. in the gastrointestinal tract; however, there is little evidence of this then improving performance and health. The data defining the benefits of probiotics are equivocal; however, at least some probiotics seem to be able to improve performance of nursery pigs. Lowering dietary protein content for a short period post-weaning will probably reduce PWD and improve intestinal health of the piglets but performance is compromised if essential amino acid levels and/or ratios are reduced below requirement.

Analysis of genetic variations at M857 locus of the a1-Fucosy- trans-ferase (FUT1) ORF in pigs

Enterotoxigenic Escherichia coli F18 (ETEC F18) is the main pathogen that causes edema disease and post-weaning diarrhea in piglets, and a1-fucosytransferase (FUT1) gene has been identified as a receptor gene encoding the receptor for ETEC F18 bacteria. In this study, the method of PCR-RFLP was used to investigate the among 21 breeds including one wild boar breed and 20 western commercial and Chinese native pig breeds (populations). The results showed that none of the individuals in all 21 breeds possessed the resistant AA genotype, the genetic polymorphisms of the FUT1 locus were only detected in two western pig breeds (Duroc and Yorkshire), Lingao pig and hybrid pig breeds, while the wild boar and all the other Chinese pig breeds only possessed the susceptible GG genotype. The results indicated that Chinese native pig breeds, unlike western pig breeds, lack the genetic background on the resistance to ETEC F18 bacteria. This may be owe to their different origination, as the resistance gene to ETEC F18 might be originated from European wild boar. It was also inferred that edema disease and post-weaning diarrhea caused by ETEC F18 had close relationship with the growth speed of pigs.

Estimating transmission parameters of F4+ E. coli for F4-receptor-positive and -negative piglets: one-to-one transmission experiment

F4+ Escherichia coli is an important agent of post-weaning diarrhoea in piglets. Piglets that express an adhesion site for F4+ E. coli in their small intestine (F4R+) shed higher numbers of F4+ E. coli than piglets lacking this site (F4R-). We hypothesized that F4R+ piglets are more infectious and more susceptible for F4+ E. coli. This implies that in populations with F4R+ and F4R- piglets, the transmission would be dependent on the frequency of both types of animals. To quantify the difference in infectiousness and susceptibility, a one-to-one transmission experiment was performed with 20 pairs consisting of one inoculated and one contact piglet. Based on the contact infections observed, transmission parameters were estimated with generalized linear models. F4R+ piglets were infectious for other piglets and the reproduction ratio (R0) for homogeneous F4R+ populations, that is the average number of secondary infections that one F4R+ pig will cause during its entire infectious period in a population of susceptible F4R+ individuals only, was estimated as 7.1. F4R+ piglets were more susceptible than F4R- piglets and reducing the fraction of F4R+ piglets of a population will reduce transmission. It was calculated that in order to prevent major outbreaks of F4+ E. coli (R0 < 1), the fraction of F4R+ piglets must be lower than 0.14.

Binding of a monoclonal antibody positively correlates with bioactivity of the F4 fimbrial adhesin FaeG associated with post-weaning diarrhoea in piglets

Piglets are susceptible to F4 (K88) + enterotoxigenic Escherichia coli (ETEC)-induced neonatal and post-weaning diarrhoea. The F4 fimbriae are composed of some minor subunits and the major subunit FaeG that also constitutes the adhesin. Parenteral vaccination of sows with an F4-containing vaccine protects the suckling piglets against neonatal F4 + ETEC-induced diarrhoea, but no commercial (mucosal) vaccine exists against F4 + ETEC-induced weaning diarrhoea. To develop a vaccine, a bioactive F4-receptor (F4R) binding FaeG molecule is required that binds to the F4R following oral immunization and induces a FaeG-specific immune response. The present study reports the altered binding of the FaeG-specific monoclonal antibody IMM01 with bioactive versus non-bioactive F4 fimbrial adhesin FaeG. The correlation of altered IMM01 binding with altered FaeG bioactivity permits the use of an IMM01-based ELISA as a fast, specific and sensitive in vitro selection for potent F4 or (recombinant) FaeG antigen formulations, useful in an F4 + ETEC vaccine.

Sensibilidade antimicrobiana de amostras de Escherichia coli isoladas de leitões com diarréia após o desmame

The main infectious agent responsible by post-weaning diarrhoea in piglets is the Escherichia coli and the therapy by drugs is used for control of this disease. The antimicrobial sensitivity of 66 strains of Escherichia coli isolated from piglets with post-weaning diarrhoea was studied. The results show high resistance at four drugs (streptomycin, sulfonamide, tetracycline and chloramphenicol). Gentamycin and neomycin were the best antimicrobial in the inhibition of strains of Escherichia coli, isolated from piglets with post-weaning diarrhoea, in the southwest of Parana.

The effect of stressors encountered at weaning by three week old piglets on the shedding of an enterotoxigenic Escherichiacoli

The results presented here represent part of a large study designed to investigate the effects of commercial weaning practice on immune function and susceptibility to post-weaning diarrhoea in piglets weaned at 3-4 weeks of age. For the purposes of this experiment, it was considered that weaning, mixing and a short-term cold stress (10°C for 48 hours only) were likely to be the most important stressors commonly encountered at weaning. It has been known for many years that stress can play an important role in the aetiology of disease in man and animals (Kelley, 1980) but little information is available on the effects of these stressors on post-weaning diarrhoea.

The effect of stressors encountered at weaning by three week old piglets on the shedding of an enterotoxigenic Escherichiacoli

The results presented here represent part of a large study designed to investigate the effects of commercial weaning practice on immune function and susceptibility to post-weaning diarrhoea in piglets weaned at 3-4 weeks of age. For the purposes of this experiment, it was considered that weaning, mixing and a short-term cold stress (10°C for 48 hours only) were likely to be the most important stressors commonly encountered at weaning. It has been known for many years that stress can play an important role in the aetiology of disease in man and animals (Kelley, 1980) but little information is available on the effects of these stressors on post-weaning diarrhoea.

Confirmation that DNA encoding the major fimbrial subunit of Av24 fimbriae is homologous to DNA encoding the major fimbrial subunit of F107 fimbriae

Plasmid DNA from porcine enterotoxigenic Escherichia coli strain Av24 (O 141:K85ab) was cloned into recipient E. coli strain JM105 using the plasmid vector pUC18. Clones were obtained that produced fimbriae which reacted with antisera specific to the fimbriae produced by strain Av24. Restriction mapping of cloned DNA, PCR with fedA primers and DNA sequencing showed a portion of the cloned DNA to be homologous to that encoding the major fimbrial subunit of F107 fimbriae. This confirms that the fimbriae possessed by strains of E. coli causing both edema disease and post-weaning diarrhoea in piglets are variants of the same fimbriae.

Confirmation that DNA encoding the major fimbrial subunit of Av24 fimbriae is homologous to DNA encoding the major fimbrial subunit of F107 fimbriae

Plasmid DNA from porcine enterotoxigenic Escherichia coli strain Av24 (O141:K85ab) was cloned into recipient E. coli strain JM105 using the plasmid vector pUC18. Clones were obtained that produced fimbriae which reacted with antisera specific to the fimbriae produced by strain Av24. Restriction mapping of cloned DNA, PCR with fedA primers and DNA sequencing showed a portion of the cloned DNA to be homologous to that encoding the major fimbrial subunit of F107 fimbriae. This confirms that the fimbriae possessed by strains of E. coli causing both edema disease and post-weaning diarrhoea in piglets are variants of the same fimbriae.

Cold stress and post-weaning diarrhoea in piglets inoculated orally or by aerosol

ABSTRACTThree-week old piglets were subjected to two levels of moderate, chronic cold stress immediately post-weaning and inoculated orally or by aerosol with an enterotoxigenic strain ofEscherichia coli. Oral challenge, as well as both piglet-produced and artificial aerosols ofE. coliwere capable of inducing infection. In infected animals, live-weight gain and food conversion efficiency were significantly worse at 15°C than at 20° or 30°C. The incidence and severity of diarrhoea was greatest at 15°C and least at 30°C, but only in those piglets fedad libitum. Piglets fed at a restricted level kept at 15°C did not become infected or suffer a check in growth after inoculation.In the absence of other risk factors, piglets kept at thermoneutrality are unlikely to suffer post-weaning diarrhoea even in the presence of an enterotoxigenic strain ofE. coli. Diarrhoeic piglets did not exhibit the normal rise in food intake at temperatures below their thermoneutral zone. Traditionally, the design specification and control of the thermal environment in a piggery has been based on the performance of predominantly healthy pigs but the results of this study imply that the additional criterion of health can now be used.