88 research outputs found
Increased dietary zinc oxide changes the bacterial core and enterobacterial composition in the ileum of piglets
This study was conducted to investigate the effects of increased dietary ZnO
on the bacterial core and enterobacterial composition in the small intestine
of piglets that were fed diets containing a total of 124 or 3,042 mg of Zn per
kilogram of diet, respectively. Zinc was supplemented to the basal diet as
ZnO. Bacterial 16S rRNA genes of ileal DNA extracts were PCR-amplified with 2
bar-coded primer sets and sequenced by 454 pyrosequencing. The bacterial core
species were calculated from the relative abundances of reads present in 5 of
6 samples per group and at a minimum of 5 sequences per sample. The reference
database SILVA was used to assign sequence reads at an alignment minimum of
200 bases and 100% identity. Lactic acid bacteria dominated the bacterial
core, but showed diverse responses to dietary ZnO. Of the dominant
Lactobacillus spp., Lactobacillus reuteri was reduced due to increased dietary
ZnO (44.7 vs. 17.9%; P=0.042), but L. amylovorus was not influenced. However,
the changes of relative abundances of other lactic acid bacteria were more
noteworthy; Weissella cibaria (10.7 vs. 23.0%; P=0.006), W. confusa (10.0 vs.
22.4%; P=0.037), Leuconostoc citreum (6.5 vs. 14.8%; P=0.009), Streptococcus
equinus (0.14 vs. 1.0%; P=0.044), and S. lutetiensis (0.01 vs. 0.11%; P=0.016)
increased in relative abundance. Nonlactic acid bacteria that were influenced
by increased dietary ZnO included the strict anaerobic species, Sarcina
ventriculi, which showed a strong numerical decrease in relative abundance
(14.6 vs. 5.1%). Species of the Enterobacteriaceae increased their relative
abundance, as well as species diversity, in the high dietary ZnO experimental
group. Bacterial diversity indices were increased due to increased dietary ZnO
(P < 0.05), which was traced back to the increase of sequences from
subdominant species. Increased dietary ZnO led to an increase of less
prominent species and, thus, had a major impact on the bacterial composition
and diversity in piglets. This effect may help to stabilize the intestinal
microbiota in the sensitive postweaning period
Down-regulation of monocarboxylate transporter 1 (MCT1) gene expression in the colon of piglets is linked to bacterial protein fermentation and pro- inflammatory cytokine-mediated signalling
The present study investigated the influence of bacterial metabolites on
monocarboxylate transporter 1 (MCT1) expression in pigs using in vivo, ex vivo
and in vitro approaches. Piglets (n 24) were fed high-protein (26 %) or low-
protein (18 %) diets with or without fermentable carbohydrates. Colonic
digesta samples were analysed for a broad range of bacterial metabolites. The
expression of MCT1, TNF-α, interferon γ (IFN-γ) and IL-8 was determined in
colonic tissue. The expression of MCT1 was lower and of TNF-α and IL-8 was
higher with high-protein diets (P< 0·05). MCT1 expression was positively
correlated with l-lactate, whereas negatively correlated with NH3 and
putrescine (P< 0·05). The expression of IL-8 and TNF-α was negatively
correlated with l-lactate and positively correlated with NH3 and putrescine,
whereas the expression of IFN-γ was positively correlated with histamine and
4-ethylphenol (P< 0·05). Subsequently, porcine colonic tissue and Caco-2 cells
were incubated with Na-butyrate, NH4Cl or TNF-α as selected bacterial
metabolites or mediators of inflammation. Colonic MCT1 expression was higher
after incubation with Na-butyrate (P< 0·05) and lower after incubation with
NH4Cl or TNF-α (P< 0·05). Incubation of Caco-2 cells with increasing
concentrations of these metabolites confirmed the up-regulation of MCT1
expression by Na-butyrate (linear, P< 0·05) and down-regulation by TNF-α and
NH4Cl (linear, P< 0·05). The high-protein diet decreased the expression of
MCT1 in the colon of pigs, which appears to be linked to NH3- and
TNF-α-mediated signalling
Performance, digestive disorders and the intestinal microbiota in weaning rabbits are affected by a herbal feed additive
[EN] A herbal feed additive (Digestarom(R), containing a mixture of onion, garlic, caraway, fennel, gentian, melissa, peppermint, anise, oak bark and clove) was fed to rabbit does and kits to study its impact on performance, post-weaning digestive disorders and intestinal microbiota. Two groups of 9 doe rabbits and their offspring, after weaning, were fed a standard diet without or with the addition of 300 mg Digestarom(R)/kg diet. Forty kits from each group were weaned at 28 d of age weighing 0.614±0.005 kg. They were caged in groups of four rabbits (10 cages/treatment) and fed the same diet as their mothers for 13 d. Weight gain and feed intake of the kits fed Digestarom(R) was 18 and 14% higher, respectively, than those fed control diet (P<0.001), with no differences in the feed conversion. Rabbits were killed 13 d after weaning and 10 healthy animals from the Digestarom(R) group and 10 healthy and 10 diseased animals from the control group were dissected. Healthy rabbits fed control diet and those fed Digestarom(R) showed closer intestinal digesta dry matter, pH and volatile fatty acid (VFA) profi les, compared to diseased animals. VFA concentration in the small intestine was higher (P=0.030) in the diseased animals of the control group compared with the healthy and Digestarom(R) fed rabbits. However, no differences were observed in VFA concentration in stomach or caecum contents. The fermentation profi le of diseased animals was characterised by a higher proportion of propionic, i- and n-valeric acids in the caecal contents (P<0.001), and an increased i-butyric acid concentration in the stomach and caecum contents (P=0.014), whereas n-butyric acid was reduced (P<0.033) compared with the healthy or Digestarom(R) fed rabbits. Denaturing gradient gel electrophoresis indicated a higher caecal bacterial diversity in the control rabbits compared with kits fed Digestarom(R) (P=0.008). The reduced evenness factor (P<0.010) also indicated that the bacterial composition included more dominant species in the Digestarom(R) group. Under our experimental conditions, the tested herbal feed additive Digestarom(R) had protective effects in rabbit kits after weaning, making it an interesting alternative for establishing nutritional strategies.Krieg, R.; Vahjen, W.; Awad, W.; Sysel, M.; Kroeger, S.; Zocher, E.; Hulan, H.... (2009). Performance, digestive disorders and the intestinal microbiota in weaning rabbits are affected by a herbal feed additive. World Rabbit Science. 17(2):87-95. doi:10.4995/wrs.2009.662879517
Dietary methionine source alters the lipidome in the small intestinal epithelium of pigs
Methionine (Met) as an essential amino acid has key importance in a variety of metabolic pathways. This study investigated the influence of three dietary Met supplements (0.21% L-Met, 0.21% DL-Met and 0.31% DL-2-hydroxy-4-(methylthio)butanoic acid (DL-HMTBA)) on the metabolome and inflammatory status in the small intestine of pigs. Epithelia from duodenum, proximal jejunum, middle jejunum and ileum were subjected to metabolomics analysis and qRT-PCR of caspase 1, NLR family pyrin domain containing 3 (NLRP3), interleukins IL1β, IL8, IL18, and transforming growth factor TGFβ. Principal component analysis of the intraepithelial metabolome revealed strong clustering of samples by intestinal segment but not by dietary treatment. However, pathway enrichment analysis revealed that after L-Met supplementation polyunsaturated fatty acids (PUFA) and tocopherol metabolites were lower across small intestinal segments, whereas monohydroxy fatty acids were increased in distal small intestine. Pigs supplemented with DL-HMTBA showed a pronounced shift of secondary bile acids (BA) and sphingosine metabolites from middle jejunum to ileum. In the amino acid super pathway, only histidine metabolism tended to be altered in DL-Met-supplemented pigs. Diet did not affect the expression of inflammation-related genes. These findings suggest that dietary supplementation of young pigs with different Met sources selectively alters lipid metabolism without consequences for inflammatory status
Evaluation of Vertical Profiles and Atmospheric Boundary Layer Structure Using the Regional Climate Model CCLM during MOSAiC
Regional climate models are a valuable tool for the study of the climate processes and climate change in polar regions, but the performance of the models has to be evaluated using experimental data. The regional climate model CCLM was used for simulations for the MOSAiC period with a horizontal resolution of 14 km (whole Arctic). CCLM was used in a forecast mode (nested in ERA5) and used a thermodynamic sea ice model. Sea ice concentration was taken from AMSR2 data (C15 run) and from a high-resolution data set (1 km) derived from MODIS data (C15MOD0 run). The model was evaluated using radiosonde data and data of different profiling systems with a focus on the winter period (November–April). The comparison with radiosonde data showed very good agreement for temperature, humidity, and wind. A cold bias was present in the ABL for November and December, which was smaller for the C15MOD0 run. In contrast, there was a warm bias for lower levels in March and April, which was smaller for the C15 run. The effects of different sea ice parameterizations were limited to heights below 300 m. High-resolution lidar and radar wind profiles as well as temperature and integrated water vapor (IWV) data from microwave radiometers were used for the comparison with CCLM for case studies, which included low-level jets. LIDAR wind profiles have many gaps, but represent a valuable data set for model evaluation. Comparisons with IWV and temperature data of microwave radiometers show very good agreement
Dietary fiber and its role in performance, welfare, and health of pigs
Dietary fiber (DF) is receiving increasing attention, and its importance in pig nutrition is now acknowledged. Although DF for pigs was frowned upon for a long time because of reductions in energy intake and digestibility of other nutrients, it has become clear that feeding DF to pigs can affect their well-being and health. This review aims to summarize the state of knowledge of studies on DF in pigs, with an emphasis on the underlying mode of action, by considering research using DF in sows as well as suckling and weaned piglets, and fattening pigs. These studies indicate that DF can benefit the digestive tracts and the health of pigs, if certain conditions or restrictions are considered, such as concentration in the feed and fermentability. Besides the chemical composition and the impact on energy and nutrient digestibility, it is also necessary to evaluate the possible physical and physiologic effects on intestinal function and intestinal microbiota, to better understand the relation of DF to animal health and welfare. Future research should be designed to provide a better mechanistic understanding of the physiologic effects of DF in pigs
Effects of Zinc Source and Level in Low ABC-4 Diets on Nursery Pig Growth Performance and Fecal Characteristics
A total of 360 weanling barrows (DNA 200 × 400; initially 13.0 ± 0.07 lb) were used in a 38-d study to evaluate the effects of diets containing different levels of a novel Zn source (HiZox, Animine Precision Minerals, Annecy, France) and different levels of crude protein (CP) in low acid-binding capacity at pH 4 (ABC-4) diets on growth performance and fecal characteristics. Pigs were randomly assigned to pens (5 pigs per pen) and pens were assigned to 1 of 6 treatments with 12 pens per treatment. Diets were fed in 3 phases: phase 1 from d 0 to 10, phase 2 from d 11 to 24, and phase 3 from d 25 to 38. All diets were formulated to have low ABC-4. Treatment 1, the negative control (NC), was formulated to contain 150 ppm of Zn (HiZox) throughout the experiment (d 0 to 38). Treatment 2, the positive control (PC), was formulated to contain 3,000 ppm (phase 1) and 2,000 ppm (phase 2) of Zn (ZnO). Treatment 3 (low HiZox) contained 500 ppm (phase 1) and 300 ppm (phase 2) of Zn. Treatment 4 (low HiZox + low CP) was formulated similar to treatment 3 but contained lower CP (19.3% CP) than the NC, PC, low, and high HiZox treatments (21.3% CP). Treatment 5 (high HiZox) contained 800 ppm (phase 1) and 500 ppm (phase 2) of Zn. Treatment 6 (high HiZox + low CP) was formulated to be similar to treatment 5 but contained less CP (19.3% CP). In phase 3, all pigs were fed a common diet containing 150 ppm of Zn (HiZox) and 21.3% CP. For the experimental period (d 0 to 24), pigs fed high HiZox + low CP had poorer F/G (P \u3c 0.05) than NC, PC, low HiZox, and high HiZox. In addition, ADG (quadratic, P = 0.007) and ADFI (quadratic, P = 0.018) increased as HiZox increased, and pigs fed diets with low CP were less feed efficient (P = 0.043) than those fed the same levels of HiZox but with high CP. Overall, pigs fed low CP diets had poorer F/G (P = 0.041) than pigs fed similar levels of HiZox with high CP. For fecal characteristics, pigs fed low CP had higher (P = 0.008) dry matter (DM) and an interaction between day and CP (P = 0.040) was detected for fecal scores with low CP diets improving stool consistency to a greater extent on d 10 than on d 23. In summary, increasing levels of HiZox improved performance of nursery pigs during phases 1 and 2, and pigs fed a regimen of 800 and 500 ppm of HiZox in the first 2 phases in low ABC-4 diets had similar performance to pigs fed pharmacological levels of Zn from ZnO in the overall period. Finally, pigs fed low CP diets had improved fecal characteristics, but poorer F/G throughout the nursery period
The High-Acceptance Dielectron Spectrometer HADES
HADES is a versatile magnetic spectrometer aimed at studying dielectron
production in pion, proton and heavy-ion induced collisions. Its main features
include a ring imaging gas Cherenkov detector for electron-hadron
discrimination, a tracking system consisting of a set of 6 superconducting
coils producing a toroidal field and drift chambers and a multiplicity and
electron trigger array for additional electron-hadron discrimination and event
characterization. A two-stage trigger system enhances events containing
electrons. The physics program is focused on the investigation of hadron
properties in nuclei and in the hot and dense hadronic matter. The detector
system is characterized by an 85% azimuthal coverage over a polar angle
interval from 18 to 85 degree, a single electron efficiency of 50% and a vector
meson mass resolution of 2.5%. Identification of pions, kaons and protons is
achieved combining time-of-flight and energy loss measurements over a large
momentum range. This paper describes the main features and the performance of
the detector system
Environmentally Acquired Bacillus and Their Role in C. difficile Colonization Resistance
Clostridioides difficile is an environmentally acquired, anaerobic, spore-forming bacterium which ordinarily causes disease following antibiotic-mediated dysbiosis of the intestinal microbiota. Although much is understood regarding the life cycle of C. difficile, the fate of C. difficile spores upon ingestion remains unclear, and the underlying factors that predispose an individual to colonization and subsequent development of C. difficile infection (CDI) are not fully understood. Here, we show that Bacillus, a ubiquitous and environmentally acquired, spore-forming bacterium is associated with colonization resistance to C. difficile. Using animal models, we first provide evidence that animals housed under conditions that mimic reduced environmental exposure have an increased susceptibility to CDI, correlating with a loss in Bacillus. Lipopeptide micelles (~10 nm) produced by some Bacilli isolated from the gastro-intestinal (GI)-tract and shown to have potent inhibitory activity to C. difficile have recently been reported. We show here that these micelles, that we refer to as heterogenous lipopeptide lytic micelles (HELMs), act synergistically with components present in the small intestine to augment inhibitory activity against C. difficile. Finally, we show that provision of HELM-producing Bacillus to microbiota-depleted animals suppresses C. difficile colonization thereby demonstrating the significant role played by Bacillus in colonization resistance. In the wider context, our study further demonstrates the importance of environmental microbes on susceptibility to pathogen colonization
Invariant-mass and [gamma]-ray spectroscopy using secondary, radioactive ion beams
Coulomb excitation of secondary beams (5 < Z < 20) at energies
around 250 .1 MeV was explored at GSI. For low-lying states, 7-ray spectroscopy
was utilized, while high-lying excitations were investigated by
means of invariant-mass spectroscopy
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