Changing dietary calcium-phosphorus level and cereal source selectively alters abundance of bacteria and metabolites in the upper gastrointestinal tracts of weaned pigs. Appl Environ Microbiol. 2013;79:7264-7272. [PMID: 24038702 DOI: 10.1128/AEM.02691-13]

Dietary calcium concentration and cereals differentially affect mineral balance and tight junction proteins expression in jejunum of weaned pigs

Ca plays an essential role in bone development; however, little is known about its effect on intestinal gene expression in juvenile animals. In the present study, thirty-two weaned pigs (9·5 (SEM 0·11) kg) were assigned to four diets that differed in Ca concentration (adequate v. high) and cereal composition (wheat-barley v. maize) to assess the jejunal and colonic gene expression of nutrient transporters, tight junction proteins, cytokines and pathogen-associated molecular patterns, nutrient digestibility, Ca balance and serum acute-phase response. To estimate the impact of mucosal bacteria on colonic gene expression, Spearman's correlations between colonic gene expression and bacterial abundance were computed. Faecal Ca excretion indicated that more Ca was available along the intestinal tract of the pigs fed high Ca diets as compared to the pigs fed adequate Ca diets (P> 0.05). High Ca diets decreased jejunal zonula occludens 1 (ZO1) and occludin (OCLN) expression, up-regulated jejunal expression of toll-like receptor 2 (TLR2) and down-regulated colonic GLUT2 expression as compared to the adequate Ca diets (P< 0.05). Dietary cereal composition up-regulated jejunal TLR2 expression and interacted (P= 0.021) with dietary Ca on colonic IL1B expression; high Ca concentration up-regulated IL1B expression with wheat-barley diets and down-regulated it with maize diets. Spearman's correlations (r> 0·35; P< 0·05) indicated an association between operational taxonomic units assigned to the phyla Bacteroidetes, Firmicutes and Proteobacteria and bacterial metabolites and mucosal gene expression in the colon. The present results indicate that high Ca diets have the potential to modify the jejunal and colonic mucosal gene expression response which, in turn, interacts with the composition of the basal diet and mucosa-associated bacteria in weaned pigs.

News in livestock research - use of Omics-technologies to study the microbiota in the gastrointestinal tract of farm animals

Technical progress in the field of next-generation sequencing, mass spectrometry and bioinformatics facilitates the study of highly complex biological samples such as taxonomic and functional characterization of microbial communities that virtually colonize all present ecological niches. Compared to the structural information obtained by metagenomic analyses, metaproteomic approaches provide, in addition, functional data about the investigated microbiota. In general, integration of the main Omics-technologies (genomics, transcriptomics, proteomics and metabolomics) in live science promises highly detailed information about the specific research object and helps to understand molecular changes in response to internal and external environmental factors.

The microbial communities settled in the mammalian gastrointestinal tract are essential for the host metabolism and have a major impact on its physiology and health. The microbiotas of livestock like chicken, pig and ruminants are becoming a focus of interest for veterinaries, animal nutritionists and microbiologists. While pig is more often used as an animal model for human-related studies, the rumen microbiota harbors a diversity of enzymes converting complex carbohydrates into monomers which bears high potential for biotechnological applications.

This review will provide a general overview about the recent Omics-based research of the microbiota in livestock including its major findings. Differences concerning the results of pre-Omics-approaches in livestock as well as the perspectives of this relatively new Omics-platform will be highlighted.

Necessity of monitoring blood trace elements in children with Helicobacter pylori infection

AIM: To analyze the necessity of monitoring blood trace elements in children with Helicobacter pylori (H. pylori) infection, and assess the value of trace elements in the treatment of children with H. pylori infection.

METHODS: Eighty children without H. pylori infection (control group) and 80 children with H. pylori infection (observation group) were included. The children in the observation group all accepted triple therapy for two weeks, of whom 40 additionally accepted symptomatic treatment by zinc or iron supplementation (symptomatic treatment subgroup), and another 40 received simultaneous supplementation of zinc and iron (non-symptomatic treatment subgroup). The levels of zinc, iron, copper, calcium and magnesium and the incidence of anemia were compared between the observation group and control group, and H. pylori infection, trace elements, and anemia were compared between the two subgroups after 1 mo of treatment.

RESULTS: Zinc and iron levels were significantly higher in the observation group than in the control group (P < 0.05), although there were no statistically differences in copper, calcium or magnesium levels between the two groups (P > 0.05). In the observation group, the percentages of children with zinc or iron deficiency were significantly higher than those in the control group (31.25% vs 13.75%, 36.25% vs 17.50%, P < 0.01), although the percentages of children with deficiency of other elements had no significant differences (P > 0.05). The incidence of anemia was significantly higher in the observation group than in the control group (40.00% vs 18.75%, P < 0.01). The numbers of children with zinc deficiency, iron deficiency, H. pylori infection or anemia were significantly lower in the symptomatic treatment subgroup than in the non-symptomatic treatment subgroup (5 vs 16, 2 vs 13, 3 vs 11, 1 vs 6, P < 0.05 or P < 0.01).

CONCLUSION: H. pylori infection children may develop zinc or iron deficiency and have a higher incidence of iron-deficiency anemia. Zinc or iron supplementation during H. pylori eradication treatment is conducive to recovery in H. pylori infection children.

Quantification of Gram-positive bacteria: adaptation and evaluation of a preparation strategy using high amounts of clinical tissue

Background

A preparation method for quantification of bacteria in tissues is obligatory to reduce tissue mass, concentrate the target, purify, remove inhibitory substances and to achieve constant target recovery rates. No preparation method has been available until now for a high mass of tissue applicable for routine use and analytical veterinary diagnostics.

Results

This study describes an easy-to-use tissue preparation protocol to quantify Gram-positive bacteria from a large volume of tissue matrix. A previously published sample preparation method (Matrix-Lysis) from food science was successfully adapted for clinical use on tissues from pigs, including cerebrum, spinal cord, lung, liver, ileum, colon, caecum, kidney and muscle tissue. This tissue preparation method now permits quantification of pathogens from 5 g of organic matrix, which is a 20–200 fold increase by weight compared to other methods. It is based on solubilization of the sample matrix with either a chaotrope plus detergent or divalent salts as solubilization agents. The method was designed as a modular system, offering the possibility to change lysis buffers, according to tissue solubilization characteristics and the intended detection method (molecular or culture). Using Listeria monocytogenes as model organism, viable cell quantification or DNA extraction and quantitative real-time PCR were performed after Matrix-Lysis to determine recovery rates and detection limit (LOD). The adapted Matrix-Lysis protocol resulted in high recovery rates (mean value: 76% ± 39%) for all tested organs, except kidney, and recovery was constant over 5 log scales for all tested buffer systems. The LOD for Matrix-Lysis with subsequent plate count method (PCM) was as low as 1 CFU/5 g, while for qPCR based detection the LOD was 10² bacterial cell equivalents (BCE)/5 g for two buffer systems.

Conclusions

This tissue preparation is inexpensive and can be easily used for routine and analytical veterinary diagnostics. Inoculation studies or hazard assessments can profit from this tissue preparation method and it is anticipated that this study will be a valuable source for further research on tissue preparation strategies.