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Intensive dairy and beef cattle farming contribute significantly to the emissions of greenhouse gases from Belgian agriculture. Two main breeds dominate the Belgian cattle livestock; Holstein-Friesian (HF) dairy cattle and double-muscled Belgian Blue (DMBB) beef cattle. The aim of our study was to quantify and compare methane emissions of both breeds under conditions of equal diet composition, environment and physiological stage (using heifers of the same age). The methanogen and bacterial communities were thoroughly investigated using metabarcoding to correlate taxonomic compositions with breed and methane emission levels. HF heifers had significantly higher absolute enteric methane emissions as compared to DMBB heifers. Methane production was positively correlated to the dry matter intake (DMI). Due to the significantly higher DMI and energy intake of HF heifers, methane yield per DMI was not significantly different between breeds. Furthermore, no significant differences were observed between the gross feed efficiency (GFE) of both breeds, but the DMBB heifers demonstrated significantly lower CH 4 :CO 2 ratios (mole-to-mole ratio), suggesting a more efficient fermentation by the rumen microbial ecosystem. Although both breeds accommodated a common core of taxonomic groups, the bacterial communities also showed a breed specific composition due to differential abundance of specific species belonging to the main taxonomic groups and the presence of a few species of minor taxonomic groups that were significantly associated with one of both breeds. In contrast to the bacterial communities, the methanogen community was consistent and stable between breeds and at different sampling times. Our results suggest that breed related factors influence the bacterial community composition, while the variation in methane emission levels can be attributed mainly to the feed intake of the animals. [ABSTRACT FROM AUTHOR]

Recently, we developed a DNA walking system for the detection and characterization of a broad spectrum of GMOs in routine analysis of food/feed matrices. Here, we present a new version with improved throughput and sensitivity by coupling the DNA walking system to Pacific Bioscience® Next-generation sequencing technology. The performance of the new strategy was thoroughly assessed through several assays. First, we tested its detection and identification capability on grains with high or low GMO content. Second, the potential impacts of food processing were investigated using rice noodle samples. Finally, GMO mixtures and a real-life sample were analyzed to illustrate the applicability of the proposed strategy in routine GMO analysis. In all tested samples, the presence of multiple GMOs was unambiguously proven by the characterization of transgene flanking regions and the combinations of elements that are typical for transgene constructs. [ABSTRACT FROM AUTHOR]

Biochar, a solid coproduct of biomass pyrolysis, has recently been proposed as soil amendment in agriculture. We studied the effect of biochar on soil and substrate physicochemical properties, plant growth, disease susceptibility and rhizosphere microbiology in two contrasting cropping systems, i.e., lettuce grown in field soil and strawberry grown in white peat. For both systems, changes in the physicochemical properties of the plant growth media were observed. In the lettuce bio-assay, biochar addition had no effect on crop growth, crop health ( Rhizoctonia solani infection test) and rhizosphere microbiology. In contrast, in the strawberry bioassay, addition of 3% biochar to peat resulted in (i) a higher fresh and dry plant weight, (ii) a lower susceptibility for the fungal pathogen Botrytis cinerea on both leaves and fruits, and (iii) changes in the rhizosphere microbiology, analysed by Phospholipid Fatty Acid (PLFA) profiling and 16S rDNA amplicon sequencing. Biochar addition led to an increase of bacterial diversity and a shift in composition of the rhizosphere microbiota. Extra inorganic plant nutrition and lime added to the peat reduced these effects of biochar on the strawberry plants. We conclude that in certain plant growth media, biochar amendment can result in chemical changes that induce multiple responses in the plant, including shifts in the rhizosphere microbiome. Biochar can be beneficial for plant growth, especially in conditions of limited nutrient availability. [ABSTRACT FROM AUTHOR]

Because the number and diversity of genetically modified (GM) crops has significantly increased, their analysis based on real-time PCR (qPCR) methods is becoming increasingly complex and laborious. While several pioneers already investigated Next Generation Sequencing (NGS) as an alternative to qPCR, its practical use has not been assessed for routine analysis. In this study a statistical framework was developed to predict the number of NGS reads needed to detect transgene sequences, to prove their integration into the host genome and to identify the specific transgene event in a sample with known composition. This framework was validated by applying it to experimental data from food matrices composed of pure GM rice, processed GM rice (noodles) or a 10% GM/non-GM rice mixture, revealing some influential factors. Finally, feasibility of NGS for routine analysis of GM crops was investigated by applying the framework to samples commonly encountered in routine analysis of GM crops. [ABSTRACT FROM AUTHOR]