Staff Publications

Staff Publications

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    'Staff publications' is the digital repository of Wageningen University & Research

    'Staff publications' contains references to publications authored by Wageningen University staff from 1976 onward.

    Publications authored by the staff of the Research Institutes are available from 1995 onwards.

    Full text documents are added when available. The database is updated daily and currently holds about 240,000 items, of which 72,000 in open access.

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    Feed intake, rather than digestion is the growth limiting factor in poor performing piglets
    Paredes Escobar, S.P. ; Awati, A.A. ; Jansman, A.J.M. ; Hees, H.M.J. van; Verstegen, M.W.A. ; Gerrits, W.J.J. - \ 2012
    In: Digestive Physiology of Pigs, book of abstracts, Keystone, CO, USA, May 29 - June 1, 2012. - Keystone, Co, USA : - p. 121 - 121.
    Variation in body weight gain during the nursery period has a large economic impact in pig production. Understanding the reasons for variation in animal performance and the factors that limit growth could result in management strategies to reduce this variation. To this aim, 2 distinct sub populations (Poor performers, P; High performers, H) of clinically healthy pigs were selected at 3 weeks post weaning (~6 weeks of age) based on an equation including BW at birth, weaning, 3 wk post weaning and sex. At 6 wk of age, P pigs (6.8 kg BW, SE 0.14) and H pigs (12.2 kg BW, SE 0.14), were housed individually in a high hygiene research facility and provided with high quality palatable diet (175 g/kg CP; 10.6 MJ NE; 13.5 g/kg AID Lys) until 10 wk of age. Pigs had ad libitum access to feed and water. Apparent ileal (slaughter) and total tract nutrient digestibility were measured. It was observed that fractional growth rate (i.e., ADG expressed as percentage of mean BW) was lower for H pigs than for P pigs (3.0 vs 3.3%; P <0.01). ADFI was higher for H pigs (275 g/d higher; P <0.001) than for P pigs throughout the 4 wk experimental period, while feed efficiency was not different. At the end of the experimental period, H pigs were heavier compared with P pigs (30 vs. 19 kg BW), had greater body length (73 vs. 62 cm) and head circumference (49 vs. 43 cm), all P <0.05. Apparent ileal digestibility (0.78, 0.80 and 0.81 for DM, GE and N, respectively) and total tract digestibility (0.87, 0.87 and 0.84 for DM, GE and N, respectively) were similar for P and H pigs. In conclusion, when compared with high performers, piglets identified as poor performers continued their poor performance during individual housing and optimized rearing conditions until 10 wk of age. The substantial difference in BW at 10 wk was related to differences in feed intake rather than to digestive utilization or feed conversion efficiency. We can deduct from these observations that the determinants for body weight at the end of the nursery period are already set during the first weeks of life.
    Analysis of factors to predict piglet body weight at the end of the nursery phase
    Paredes Escobar, S.P. ; Jansman, A.J.M. ; Verstegen, M.W.A. ; Awati, A. ; Buist, W.G. ; Hartog, L.A. den; Hees, H.M.J. van; Quiniou, N. ; Hendriks, W.H. ; Gerrits, W.J.J. - \ 2012
    Journal of Animal Science 90 (2012)9. - ISSN 0021-8812 - p. 3243 - 3251.
    intrauterine growth-retardation - within-litter variation - birth-weight - postnatal-growth - size - performance - sows - consequences - traits - muscle
    In pig production, within-batch variation in body weight (BW) gain of piglets during the nursery period (up to 10 weeks of age) can be high and is of high economic importance. Homogeneity of BW within batches of animals is important as it influences the efficiency of use of the grower and finisher facilities, and provides an extra value for the fattening farms. In the current study, factors for a low BW at the end of the nursery period of pigs were determined by analysing datasets from three different Swine Research Centres in the Netherlands and France. The entire dataset contained information on 77,868 individual piglets born in the period between 2005 and 2010. BW was determined at different time points over the pre- and post-weaning phase, and sex, season of birth; litter information (litter size at day of birth and after cross-fostering, number of piglets born alive per litter, number of total born littermates, sow parity number); cross-fostered animals (yes or no), and pen group size over the post-weaning period were recorded. A risk factor analysis approach was used to analyze the datasets to determine factors that predict piglet BW at the end of the nursery period. BW at the end of the nursery period corrected for age was mainly determined by season (P <0.001), sex (P <0.001), birth weight (P <0.001), weaning weight (P <0.001) and BW at 6 wk of age (P <0.001). These variables were consistent among datasets and explained approximately 70% of the overall variation in BW at the end of the nursery period. Litter information did not significantly (P > 0.05) contribute to explaining the BW at the end of the nursery period. To discard the possibility of intrauterine growth retarded piglets (IUGR) being the reason for the influence of birth weight (BiW) as an explanatory factor in the regression model, a further analysis was performed on the effect of this category of piglets on the results of the regression analysis. Overall, it was concluded that piglet's BW at the end of the nursery phase is mainly determined by season, sex, birth and weaning weight and BW at 6 weeks of age. Piglets with a BiW higher than the mean BiW minus 2.5 times the SD have the potential to compensate during the subsequent phases of growth.
    Dietary protein and fermentable carbohydrates contents influence growth performance and intestinal characteristics in newly weaned pigs
    Bikker, P. ; Dirkzwager, A. ; Fledderus, J. ; Trevisi, P. ; Huërou-Luron, I. Le; Lallès, J.P. ; Awati, A. - \ 2007
    Livestock Science 108 (2007)1-3. - ISSN 1871-1413 - p. 194 - 197.
    piglets - level
    Increasing the dietary amount of fermentable carbohydrates (FC) may counteract the negative effects of protein fermentation in newly weaned piglets. To study this hypothesis, 272 newly weaned piglets were allotted to 4 dietary treatments in a 2 × 2 factorial arrangement with low and high FC (7.5 and 13.5%) and crude protein (CP, 15 and 22%) content as respective factors. Intestinal histology, enzyme activity, microbiota and fermentation products were determined in 8 pigs per treatment 7 days post-weaning. In the 4 wk experimental period, interactions between dietary CP and FC content were found for feed intake (P = 0.022), daily gain (P = 0.001), and gain:feed (P = 0.033). The high-FC content reduced daily gain by 50 g/d in the low-CP diet, whereas the FC content did not affect growth performance in the high-CP diet. Over the 4 wk experimental period, daily gain (350 g/d) and feed intake (519 g/d) were highest for piglets on the low-CP low-FC diet. The high-FC content resulted in an increase in number of lactobacilli (P = 0.047) and a decrease of total coliforms (P = 0.06) in the small intestine. It increased the lactic acid content (P = 0.08) and reduced the ammonia content (P = 0.04) in the small intestine and increased the VFA content in the colon (P = 0.009). The reduction in CP content reduced ammonia concentration in the small intestine (P = 0.003). We concluded that dietary FC influenced microbial population and fermentation products in the gut. However, this was not reflected in an increased growth performance.
    Changes in the fermentation end-product profile in the GIT of piglets during post-colostrum suckling period
    Awati, A. ; Urso, S. D'; Williams, B.A. ; Bosch, M. ; Verstegen, M.W.A. - \ 2007
    Livestock Science 108 (2007)1-3. - ISSN 1871-1413 - p. 156 - 158.
    Pre-weaning development of microbial activity has an effect on post-weaning establishment of the gastro-intestinal tract (GIT) microbiota. An in vivo study was conducted, to evaluate the effect of age on fermentation end-product profiles during the post-colostrum suckling period, as the variation in composition of mature milk is minimum. Sixteen piglets from two litters (eight per litter) were selected. During the study, piglets had free access to sow's milk, but no creep feed, nor antibiotic treatments. Two piglets from each litter were sacrificed on d 11, 18, 25 and 32 of age. The digesta samples were collected from the beginning and end of the small intestine, caecum and colon. Samples were analyzed for fermentation end-product concentrations. Combining the results from all the GIT sites, it was observed that, total VFA concentration increased with age of the piglets. There was a significant rise in acetic acid concentrations, with a significant decrease in lactic acid concentrations from d11 to d32, while the proportions of SCFA, (acetic acid 72%, propionic acid 15% and butyric acid 6% of total VFA) and ammonia concentrations remained unchanged. These results clearly suggest that, the microbial activity in terms of fermentation end-product profile skewed from lactic acid to acetic acid as a major product during the post-colostrum suckling period. This may be attributed to lower substrate availability due to increased number of microbes or increased diversity in the microbiota in time.
    Effects of added fermentable carbohydrates in the diet on intestinal proinflammatory cytokine-specific mRNA content in weaning piglets
    Pié, S. ; Awati, A. ; Vida, S. ; Falluel, I. ; Williams, B.A. ; Oswald, I.P. - \ 2007
    Journal of Animal Science 85 (2007). - ISSN 0021-8812 - p. 673 - 683.
    total parenteral-nutrition - lactic-acid bacteria - inflammatory responses - weanling piglets - induced colitis - growing pigs - expression - performance - absorption - prebiotics
    There is increasing evidence showing that dietary supplementation with prebiotics can be effective in the treatment of intestinal inflammation. Because weaning time is characterized by rapid intestinal inflammation, this study investigated the effect of a diet supplemented with a combination of 4 fermentable carbohydrates (lactulose, inulin, sugarbeet pulp, and wheat starch) on the mRNA content of proinflammatory cytokines in newly weaned piglets. Cytokines (IL-1ß, IL-6, IL-8, IL-12p40, IL-18, and tumor necrosis factor-) were analyzed using a semiquantitative reverse-transcription PCR technique on d 1, 4, and 10 in the ileum and colon of piglets fed either a test diet (CHO) or a control diet. In addition to the diet, the effect of enforced fasting on cytokine mRNA content was also evaluated. No effect of fasting was observed on the pro-inflammatory cytokine mRNA content. Our results showed that the CHO diet induced an up-regulation of IL-6 mRNA content in the colon of piglets 4 d postweaning. This up-regulation was specific for the animals fed the CHO diet and was not observed in animals fed the control diet. An increase in IL-1ß mRNA content was also observed on d 4 postweaning in all of the piglets. Correlations between proinflammatory cytokines and the end-products of fermentation indicated that the regulation of cytokines may be linked with some of the fermentation end-products such as branched-chain fatty acids, which are in turn end-products of protein fermentation
    The effect of dietary protein and fermentable carbohydrates levels on growth performance and intestinal characteristics in newly weaned piglets
    Bikker, P. ; Dirkzwager, A. ; Fledderus, J. ; Trevisi, P. ; Huërou-Luron, I. Le; Lallès, J.P. ; Awati, A. - \ 2006
    Journal of Animal Science 84 (2006). - ISSN 0021-8812 - p. 3337 - 3345.
    chain fatty-acid - resistant starch - nonstarch polysaccharides - gastrointestinal-tract - escherichia-coli - gas-production - pigs - fiber - feed - digestibility
    Reducing the CP content and increasing the fermentable carbohydrates (FC) content of the diet may counteract the negative effects of protein fermentation in newly weaned piglets fed high-CP diets. To study the synergistic effects of CP and FC on gut health and its consequences for growth performance, 272 newly weaned piglets (26 d of age, 8.7 kg of BW) were allotted to 1 of 4 dietary treatments in a 2 x 2 factorial arrangement, with low and high CP and low and high FC content as the factors. Eight piglets from each dietary treatment were killed on d 7 postweaning. Feces and digesta from ileum and colon were collected to determine nutrient digestibility, fermentation products, and microbial counts. In addition, jejunum tissues samples were collected for intestinal morphology and enzyme activity determination. During the entire 4-wk period, interactions between the dietary CP and FC contents were found for ADFI (P = 0.022), ADG (P = 0.001), and G:F (P = 0.033). The high-FC content reduced ADFI, ADG, and G:F in the low-CP diet, whereas the FC content did not affect growth performance in the high-CP diet. Lowering the CP content of the low-FC diet improved ADFI and ADG, whereas lowering the CP content of the high-FC diet did not influence growth performance. The low-CP diets resulted in a lower concentration of ammonia in the small intestine (P = 0.003), indicating reduced protein fermentation. In the small intestine, the high FC content increased the number of lactobacilli (P = 0.047), tended to decrease the number of coliforms (P = 0.063), tended to increase the lactic acid content (P = 0.080), and reduced the concentration of ammonia (P = 0.049). In the colon, the high-FC diets increased the concentration of total VFA (P = 0.009), acetic acid (P = 0.003), and butyric acid (P = 0.018), and tended to decrease the ammonia concentration (P = 0.076). Intestinal morphology and activity of brush border enzymes were not affected by the diet, although maltase activity tended to decrease with increasing dietary FC (P = 0.061). We concluded that an increase in the dietary FC content, and to a lesser extent a decrease in the CP content, reduced ammonia concentrations and altered the microflora and fermentation patterns in the gastrointestinal tract of weaned piglets. However, these effects were not necessarily reflected by an increased growth performance of the piglets
    The effect of dietary protein and fermentable carbohydrates levels in newly weaned pigs on performance and intestinal characteristics
    Bikker, P. ; Dirkzwager, A. ; Fledderus, J. ; Trevisi, P. ; Huërou-Luron, I. Le; Lallès, J.P. ; Awati, A.A. - \ 2006
    Dietary carbohydrates with different rates of fermentation affect fermentation end-product profiles in different sites of gastro-intestinal tract of weaning piglet
    Awati, A. ; Williams, B.A. ; Bosch, M.W. ; Verstegen, M.W.A. - \ 2006
    Animal Science 82 (2006)6. - ISSN 1357-7298 - p. 837 - 843.
    large-intestine - growing pigs - polysaccharides - prebiotics
    An in vivo experiment was conducted to examine changes in fermentation end-products in the gastro-intestinal tract (GIT) of weaning piglets by the inclusion of fermentable carbohydrates in the diet. The experiment was repeated in three replicates of 36 piglets. Piglets were raised free of antibiotics and creep feeding prior to weaning at 4 weeks of age. Each replicate was conducted over a period of 10 days. The piglets were offered one of two dietary treatments: control diet (CON), and fermentable carbohydrate enriched diet (CHO); and were subjected to one of the two fasting treatments (i) fasting for 2 days in the beginning of the experimental period and (ii) non-fasting. Piglets were slaughtered on the 1st, 4th and 10th day of each period. Digesta samples were collected from: first half of small intestine, second half of small intestine, caecum, and colon. The dry matter, volatile fatty acid (VFA) profile, and ammonia concentrations were analysed. Food intake, growth and food conversion ratio were also recorded. There were no differences in production performances such as growth and food conversion ratio (FCR) between the treatment groups. Concentrations of VFA were significantly higher, while ammonia concentration was significantly lower in the CHO group compared to the CON group in different fermentation sites within the GIT (¿P
    Changes in the fermentation end product profile in the GIT of piglets during post-colostrum suckling period
    Awati, A. ; Urso, S. D'; Williams, B.A. ; Bosch, M.W. ; Verstegen, M.W.A. - \ 2006
    Post-natal development of the porcine microbiota composition and activities
    Konstantinov, S.R. ; Awati, A.A. ; Williams, B.A. ; Miller, B.G. ; Jones, P. ; Stokes, C.R. ; Akkermans, A.D.L. ; Smidt, H. ; Vos, W.M. de - \ 2006
    Environmental Microbiology 8 (2006)7. - ISSN 1462-2912 - p. 1191 - 1199.
    gradient gel-electrophoresis - lactic-acid bacteria - 16s ribosomal dna - lactobacillus - pcr - diversity - intestine - sequence - piglets - pigs
    The current study describes the development of the porcine microbiota and its metabolic activities during the neonatal and weaning period. Using 16S rRNA-based approaches, we first analysed the ileal and colonic microbiota of neonatal piglets at days 2, 5 and 12 after birth. To further investigate the effect of weaning at 3 weeks of age, 19-day-old piglets (n = 64) were randomly allocated into two groups. Half of the piglets remained with their sows throughout the study, while the remaining piglets were weaned. As revealed by sequence analysis of 16S rRNA gene amplicons, the samples of 2-day-old piglets harboured a consortium of bacteria related to Escherichia coli, Shigella flexneri, Lactobacillus sobrius, Lactobacillus reuteri and Lactobacillus acidophilus. Moreover, species-specific real-time polymerase chain reaction assays unveiled that L. sobrius and L. reuteri predominated in the ileal samples of the neonatal and unweaned piglets with population levels up to 7 × 108 cells per gram of lumen content. Following weaning, however, these two lactobacilli were detected at significantly lower levels (<103) in the ileal samples. Furthermore, a shift in composition and metabolic activities of the predominant microbiota, and emergence of clostridia and E. coli, were encountered in the intestinal samples of the piglets after the early post-weaning period
    Use of the in vitro cumulative gas production technique for pigs: an examination of alterations in fermentation products and substrate losses at various time points1
    Awati, A. ; Williams, B.A. ; Bosch, M.W. ; Li, Y.C. ; Verstegen, M.W.A. - \ 2006
    Journal of Animal Science 84 (2006)5. - ISSN 0021-8812 - p. 1110 - 1118.
    ruminant feeds - production profiles - large-intestine - rumen fluid - kinetics - fractions - silage
    An experiment was conducted to examine changes in VFA and ammonia concentrations at different time points using 4 fermentable carbohydrate-rich feed ingredients as substrates and feces of unweaned piglets as inoculum. Fecal inoculum was collected, pooled, and mixed from 9 specially raised (no creep feed or antibiotics) crossbred piglets at 3 wk of age. Inulin, lactulose, molasses-free sugar beet pulp, and wheat starch were used as substrates and were fermented in vitro for 72 h (3 replicates per substrate). Cumulative gas production was measured as an indicator of the kinetics of fermentation. In addition, 3 bottles of substrate per time point with similar contents (amounts of substrate, inoculum, and media) were incubated but were allowed to release their gas throughout incubation. For these latter bottles, fermentation fluid was sampled at incubation time points including every hour between 1 and 24 h and at 48 h, and fermentation end products (VFA, lactate, and ammonia) and OM disappearance were measured. Dry matter and ash were analyzed from the postfermentative samples. The pH of the contents from these bottles was also recorded. The correlation in time between fermentation end products and cumulative gas produced was determined. The results showed that the prolongation of fermentation to 72 h, especially in the case of fast-fermenting inulin and lactulose, may lead to a different end product profile (P <0.001) compared with the profile observed at the time at which most of the substrate has disappeared. Therefore, we concluded that the fermentation product profile at the end of in vitro fermentation at a specific time point cannot be used to compare fermentability of carbohydrate sources with different fermentation kinetics in terms of gas production.
    Effect of inclusion of fermentable carbohydrates in the diet on fermentation end-product profile in feces of weanling piglets1
    Awati, A. ; Williams, B.A. ; Bosch, M.W. ; Gerrits, W.J.J. ; Verstegen, M.W.A. - \ 2006
    Journal of Animal Science 84 (2006)8. - ISSN 0021-8812 - p. 2133 - 2140.
    chain fatty-acid - gas-production - growing pigs - bacteria - consumption - increases - excretion - fiber - age
    An in vivo experiment was conducted to monitor the changes in fermentation end products in the feces of weaning piglets due to the inclusion of selected fermentable carbohydrates in the diet. The experiment involved 3 groups of 16 piglets each. Specially raised piglets (neither antibiotics nor creep feeding) were weaned abruptly at 4 wk of age. The piglets were offered 1 of 2 dietary treatments [a control diet (CON), or a fermentable carbohydrate-enriched diet (CHO)] and were subjected to 1 of the 2 fasting treatments (fasting for 2 d at the beginning of the experimental period or nonfasting). Fecal samples were collected per rectum every day during the experimental period. Piglets were slaughtered at the end of the 10-d experimental period, and digesta samples were collected from different parts of the gastrointestinal tract (GIT): the first half of the small intestine, the second half of the small intestine, the cecum, and colon. The DM, VFA profile, and ammonia concentrations were analyzed from the fecal and digesta samples. Daily feed intake was also recorded. There was no difference in concentrations of VFA in feces between the treatment groups. Ammonia concentration was lower (P <0.05) in piglets fed the CHO diet compared with those fed the CON diet in both feces and digesta from different parts of GIT. Fasting had no effect on fermentation end products in feces. This study demonstrated that the inclusion of fermentable carbohydrates in weanling diets reduces protein fermentation along the GIT and also reduced the fecal concentration of ammonia.
    Difference in in vitro fermentability of four carbohydrates and two diets, using ileal and faecal inocula from unweaned piglets
    Awati, A. ; Bosch, M.W. ; Tagliapietra, F. ; Williams, B.A. ; Verstegen, M.W.A. - \ 2006
    Journal of the Science of Food and Agriculture 86 (2006)4. - ISSN 0022-5142 - p. 573 - 582.
    large-intestine - gas-production - gastrointestinal-tract - microbial activity - rumen fluid - fermentation - prebiotics - pigs - probiotics - bacteria
    An experiment was conducted to examine differences in the in vitro fermentability of four carbohydrate-rich feed ingredients and two weaning piglet diets with and without these ingredients, using both the ileal contents and the faeces of unweaned piglets as inocula. In the first part of the experiment, cumulative gas production was measured over time, using faecal inocula mixed from nine specially raised crossbred piglets (no creep feed or antibiotics) at 3 weeks of age. Inulin, lactulose, unmolassed sugar beet pulp, wheat starch and the two diets were used as substrates and fermented in vitro for 72 h. Gas production was measured as an indicator of the kinetics of fermentation. Fermentation end-products, including volatile fatty acids and ammonia, and organic matter loss, were also measured. For the fermentations of feed ingredients, samples were also collected for polymerase chain reaction/denaturing gradient gel electrophoresis analyses initially and after the fermentation process, to study changes in the composition of the bacterial community. This procedure was repeated 1 week later, using ileal contents from the same piglets as inoculum. There were significant differences between the inocula, in terms of both overall fermentation characteristics and composition and between the substrates. There was also a significant interaction between inocula and substrates, which suggests that there were potentially important differences in the microbial activity occurring in these two areas of the gastrointestinal tract (GIT). For the two diets, one with and one without addition of these fermentable ingredients, there were significant differences in terms of the kinetics, but less so in terms of the end-products of fermentation. It was concluded that inocula from both the small and large intestine should be used to obtain a more accurate assessment of potential feed ingredients which will stimulate fermentation in the piglet GIT
    Influence of storage temperature of colon and faecal digesta from pigs without cryogenic pre-treatment, on in vitro fermentatbility of potato starch
    Pellikaan, W.F. ; Awati, A.A. ; Verstegen, M.W.A. ; Gerrits, W.J.J. - \ 2005
    Prebiotics in piglet nutrition? Fermentation kinetics along the GI tract
    Awati, A.A. - \ 2005
    Wageningen University. Promotor(en): Martin Verstegen, co-promotor(en): B.A. Williams; M.W. Bosch. - Wageningen : S.n. - ISBN 9789085041641 - 143
    biggen - anti-infectieuze middelen - koolhydraten - fermentatie - kinetica - voedertoevoegingen - microbiële ecologie - varkensvoeding - voedingsfysiologie - piglets - antiinfective agents - carbohydrates - fermentation - kinetics - feed additives - microbial ecology - pig feeding - nutrition physiology

    Keywords: fermentation, gas production, piglets

    The generalized theory behind the carbohydrate to protein fermentation in the GIT is that in presence of fermentable carbohydrate substrate, microbes prefer to ferment carbohydrate source to derive energy and use the nitrogen available for their own growth. With this background information, it was hypothesized that inclusion of fermentable carbohydrates in the piglet diet will reduce the protein fermentation, which will be confirmed by reduced levels of ammonia and branched chain fatty acids in end product profile of the fermentation. The aim of this thesis was to study the effects of inclusion of fermentable carbohydrates in weaning piglets' diet, on GIT fermentation and any changes in microbial community composition and activity. Weaning process in an intensified pig production system brings many sudden changes in the environmental and physical factors in piglets' life. These sudden changes, especially in diet cause serious imbalance in the microbial community. Quicker stabilization and diversification of microbial community post weaning, is crucial in attending the gut health and reducing the risk of pathogenic infections by 'Colonization resistance: As part of this overall aim, the in vitro cumulative gas production technique was used to study the fermentation of selected fermentable substrates. While these substrates namely lactulose, inulin, wheat starch and sugar beet pulp (SBP) were included in test diet and their effect on GIT fermentation was studied in vivo. The combination of microbial community analysis based on fingerprinting techniques such as denaturing gradient gel electrophoresis (DGGE) with nutritional analysis of fermentation end product profiles, was used in vivo and in vitro studies. In in vivo trials, emphasis was given on using combination of slow fermenting carbohydrate sources such as, SBP and wheat starch with fast fermenting lactulose and inulin. The hypothesis behind this approach was to induce carbohydrate fermentation along the GIT, by providing carbohydrate substrate for the microbiota in different parts of GIT. Especially by taking in to account the difference in the transit time of feed in the different parts of GIT, it was expected that fast fermenting lactulose and inulin would be fermented in small intestine while wheat starch somewhere in the beginning of the large intestine while, SBP will reach the distal part of colon. It was found that fermentation along the GIT was improved or in other words skewed more towards the carbohydrate fermentation in vivo. It was observed in vivo that inclusion of fermentable carbohydrates in the diet reduces the protein fermentation in the GIT and ammonia concentration in end product profile. This decrease was observed along the GIT and in time in faecal fermentation end product profiles post weaning. Microbial community analysis using fingerprinting techniques revealed that inclusion of fermentable carbohydrates stabilized and diversified microbial community in the ileum as well as in the colon by day 10 post weaning. This way, the prebiotic effects of fermentable carbohydrates was evidenced. -
    Effect of substrate adaptation on the gas production kinetics and fermentation end-product profile of faecal microflora studied in-vitro
    Awati, A.A. ; Williams, B.A. ; Bosch, M.W. ; Verstegen, M.W.A. - \ 2005
    In vitro assessment of gastrointestinal tract (GIT) fermentation: Fermentable substrates and microbial activity
    Williams, B.A. ; Bosch, M.W. ; Awati, A.A. ; Konstantinov, S.R. ; Smidt, H. ; Akkermans, A.D.L. ; Verstegen, M.W.A. ; Tamminga, S. - \ 2005
    Animal Research 54 (2005)3. - ISSN 1627-3583 - p. 191 - 201.
    gel-electrophoresis analysis - volatile fatty-acids - gas-production - large-intestine - culture system - fecal flora - bacteria - colon - feces - diet
    Recently, it has become apparent that GIT fermentation is not only of interest for ruminant animals, but also for monogastrics. While it is now widely accepted that the fermentation process and its resultant end-products can have important influences on animal health, little is known about the microbiological and immunological processes involved. In terms of animal health, most interest at the moment is focussed on those moments in animals' lives when they are faced with sudden changes resulting in stress. The period of weaning in piglets is a typical example of this. The most easily accomplished and appropriate way to influence GIT fermentation processes is that of dietary intervention. This is reflected by the widespread interest in so-called pre- and pro-biotics. Given the complexities of the interactions occurring in the animal itself, it is hardly surprising that in vitro techniques are being widely used: firstly to examine potential substrates for their fermentability and possible inclusion in diets, and secondly, to assess changes in the microbial populations in response to these substrates. This paper will review the techniques currently in use for these two aspects of monogastric fermentation, and provide examples of their use.
    Effect of substrate adaptation on the microbial fermentation and microbial composition of faecal microbiota of weaning piglets studied in vitro
    Awati, A.A. ; Konstantinov, S.R. ; Williams, B.A. ; Akkermans, A.D.L. ; Bosch, M.W. ; Smidt, H. ; Verstegen, M.W.A. - \ 2005
    Journal of the Science of Food and Agriculture 85 (2005)10. - ISSN 0022-5142 - p. 1765 - 1772.
    gradient gel-electrophoresis - large-intestine - gas-production - rumen fluid - communities - prebiotics - feces
    The in vitro cumulative gas production technique can be used to assess microbial activity of a complex community, in relation to fermentation of a particular energy source. Therefore, in combination with an in vivo study to examine the effects of two different diets for weaning piglets, microbial activities of faeces were compared from animals on the two different diets. The two diets were: CHO diet [containing added fermentable carbohydrates, including sugarbeet pulp (SBP) and wheat starch (WST)], and control diet without any added fermentable carbohydrates. Neither diet contained antibiotics or extra added copper. Twenty-four piglets were selected from 12 litters (two per litter), weaned at 4 weeks of age (neither creep feeding nor any antibiotic treatment before and during the study), and introduced to one of the two diets. After 9 days on the diet, faecal samples were collected from selected animals, and tested for their activity in terms of gas production kinetics, and end-products such as volatile fatty acids, ammonia and dry matter disappearance of the two test substrates SBP and WST. The bacterial diversity was also analysed before and after in vitro fermentation using denaturing gradient gel electrophoresis analysis of amplified 16S rRNA genes. There were differences both in kinetics and end-products of the substrates. More interestingly, significant differences were detected between inocula, although mainly in terms of fermentation kinetics of the two substrates. With the CHO inoculum, SBP was fermented faster than with the control, while this effect was reversed for WST. Significantly higher diversity, as measured by DGGE fingerprint analysis, was detected in the microbial community enrichment on SBP as compared with WST at the end of fermentation. The difference between the kinetics of SBP compared with WST fermentation by faecal microbiota from the CHO diet fed piglets suggests better adaptation to SBP fermentation than to WST fermentation. The WST fermentation was more unexpected, given that a significant amount of starch is known to be fermentable by the small intestinal microbiota. It was concluded that the microbial community composition and activity in the GIT may be changed in response to diet, and that this change can be detected in vitro.
    In vitro assessment of GIT fermentation: fermentable substrates and microbial activity
    Williams, B.A. ; Bosch, M.W. ; Awati, A.A. ; Konstantinov, S.R. ; Akkermans, A.D.L. ; Verstegen, M.W.A. - \ 2004
    Effect of substrate adaptation on the gas production kinetics and microbial fermentation end-product profile of faecal microflora studied in vitro
    Awati, A.A. ; Williams, B.A. ; Bosch, M.W. ; Verstegen, M.W.A. - \ 2004
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