To study the interaction between the levels of protein and fiber on the productive performance and health status of piglets, ninety-six 35-d-old piglets (9.11 +/- 0.60 kg of BW) were placed in 32 pens of 3 animals each and allotted to 4 dietary treatments for 21 d. The 4 diets were based on rice, dairy products, and soybean meal in a 2 x 2 factorial arrangement of treatments, with 2 levels of CP (15.4 vs. 19.4%, as-fed basis) and 2 levels of dietary fiber [DF; low fiber (LF) 5.3% NDF and high fiber (HF) 7.15% NDF, as-fed basis]. The HF diet was developed by supplementing the basal diet with 40 g/kg of wheat bran and 20 g/kg of sugar beet pulp. Animal performance was obtained weekly with samples of feces collected for microbiology on the first and the last experimental day and scored from 1 (liquid) to 4 (hard). On the last day, 1 pig from each pen was sampled for blood analyses of the acute-phase protein, major acute-phase protein of pigs (PigMap) and subsequently killed to register the digestive tract weight (including contents) and colon histology. Pigs fed the HF diets had greater ADG (390 vs. 457 g; P < or = 0.001) and large intestine weight (4.4 vs. 5.4% of BW; P < or = 0.05). This coincided with a greater (P < or = 0.05) short-chain fatty acid concentration (especially of acetic and butyric acids), a decrease in Escherichia coli counts (7.77 vs. 6.86 log of cfu/g of feces, P < or = 0.05), and an increase in the ratio of lactobacilli:enterobacteria (0.76 vs. 1.37, P < or = 0.05). However, CP level did not modify the productive performance, but 20% CP increased P < or = 0.05) the relative weight (% of BW) of the small (6.5 vs. 7.7) and large intestine (3.8 vs. 4.3). In the large bowel, the 20% CP diet increased the numbers of goblet cells (4.6 vs. 5.4/100 microm; P< or = 0.05) and reduced the numbers of intraepithelial lymphocytes (1.8 vs. 1.3/100 microm; P < or = 0.05). In relation to health status, increasing DF was dependent of the dietary CP content. Supplementing the 16% CP diet with DF reduced the fecal score and increased the antibiotics interventions, whereas the opposite was the case in the 20% CP diet. Pigs fed the 20% CP diet showed decreased (P < or = 0.05) PigMap concentrations than pigs fed 16% CP diets. As a whole, CP showed major effects on the gastrointestinal weight and gut barrier integrity, whereas DF increased the productive performance and promoted major changes in the microbial colonization and fermentation variables.

No abstract

No abstract

The inclusion of fibre has been studied as an alternative to antimicrobials in weaning pig diets, while ZnO is used as an effective method to prevent post-weaning diarrhoea. However, it has not been investigated to what extent these two strategies interact with each other. The present study was designed to evaluate the effects of including wheat bran (WB) and ZnO alone or combined in the diet of early-weaning pigs on productive performance and microbial activity in the gastrointestinal tract (trial 1). A total of sixty-four piglets were distributed in a 2 £ 2 factorial combination of two levels of WB (0 v. 40 g/kg) and ZnO (0 v. 3 g/kg) in the diet. The inclusion of ZnO in the diet improved the feed intake and growth of the animals and reduced the incidence of diarrhoea. The inclusion of WB increased SCFA concentrations and decreased Escherichia coli counts. However, simultaneous incorporation of WB and ZnO increased E. coli counts. Two in vitro trials were also designed to clarify hypotheses derived from the in vivo test: (1) the ability of WB and other fibre sources to bind E. coli in vitro (trial 2) and (2) the in vitro interactions between WB and ZnO with respect to E. coli growth (trial 3). We can conclude that incorporation of WB in the diet improved gut health by modulating the activity and composition of the microbial population. The negative interaction between WB and ZnO raises the interest of considering the inclusion of phytase enzymes to reduce the therapeutic levels of ZnO in post-weaning diets.

No abstract

Casein glycomacropeptide (CGMP), a glycoprotein originating during cheese manufacture, has shown promising effects by promoting the growth of some beneficial bacteria in vitro, although its activity has not been well explored. The present study was designed to evaluate the effects of CGMP against enterotoxigenic Escherichia coli (ETEC) K88 in vitro (Trial 1) and in vivo (Trial 2). In Trial 1, increasing concentrations of CGMP (0, 0·5, 1·5 or 2·5 mg/ml) were tested regarding its ability to block the attachment of ETEC K88 to ileal mucosa tissues obtained from piglets. Increasing the concentration of CGMP resulted in a gradual decrease in ETEC K88 attachment to the epithelial surface. In Trial 2, seventy-two piglets were distributed in a 2 £ 2 factorial combination including or omitting CGMP in the diet (control diet v. CGMP) and challenged or not with ETEC K88 (yes v. no). Inclusion of CGMP increased crude protein, ammonia and isoacid concentrations in colon digesta. CGMP also increased lactobacilli numbers in ileum and colon digesta, and reduced enterobacteria counts in mucosa scrapings and the percentage of villi with E. coli adherence measured by fluorescence in situ hybridisation. The inclusion of CGMP in the diets of challenged animals also prevented the increase of enterobacteria in ileal digesta. We can conclude that CGMP may improve gut health by diminishing the adhesion of ETEC K88 to the intestinal mucosa, by increasing the lactobacilli population in the intestine and by reducing the overgrowth of enterobacteria in the digestive tract of piglets after an ETEC K88 challenge.Key words: Bovine glycomacropeptide: Piglets: Microbiota: Intestinal health Adherence of bacteria to the intestinal epithelium is known to be a prerequisite step for the colonisation and infection of the gastrointestinal tract by many pathogens. Some strains of pathogenic Escherichia coli have developed mechanisms of adhesion to intestinal (1) or renal cells (2) . In particular, enterotoxigenic E. coli (ETEC) strains adhere to receptors on the intestinal epithelium by proteinaceous surface appendages called fimbriae (3) . ETEC expressing the K88 fimbrial antigen is the most common pathogroup in young pigs (1) , and glycoproteins, sialoglycoproteins or glycosphingolipids are considered the main receptors for different K88 (ab, ac or ad) fimbrial variants (4 -7) .The potential of certain compounds to inhibit the adherence of micro-organisms, specifically E. coli, to the intestinal epithelium has been studied in vitro by various authors. Schwertmann et al. (8) and Shahriar et al. (9) described the potential of different milk glycoproteins to bind the fimbriae of E. coli and to inhibit the F4ac-positive E. coli attachment to intestinal villi in vitro. Naughton et al. (10) also described different types of prebiotics (non-digestible oligosaccharides) capable of reducing the numbers of E. coli in jejunal organ cultures of pigs. Some reports suggest that milk contains glycoconjugates that have structural homology to the glycan moi...

No abstract