85,441 research outputs found
The future of the Dutch egg processing industry
This research examines the competitiveness of the Dutch egg products industry, as well as the consequences of tightening up the laws concerning layer poultry on the competitive position of the Dutch egg production industry. A tightening of the laws has, in fact, the effect of raising the production cost, and in this research the central question revolves around whether animal welfare-friendly egg products are perceived as products with added value by the buyers of egg products (mainly industrial buyers) and will thus also be offered for sale at a higher price. Furthermore, it will be investigated what the probable developmental directions are in the egg products industry if this higher price cannot be realise
Animal welfare in poultry production systems: impact of EU standards on world trade
Animal welfare receives more legislative attention in the European Union (EU) than in many other regions of the world. Animal welfare standards for poultry are generally taken to be higher in the EU than in producing countries exporting to the EU, particularly developing countries. The recent action plan for animal welfare introduced by the European Commission aims to further expand the body of regulatory standards. In broiler production worldwide, birds are mainly kept on litter. Recently the EU agreed on a new Directive to set standards for maximum bird density. However, this is not considered likely to have a great impact on global trade. At present, the difference in animal conditions, including bird density, in Brazil and Thailand is limited compared to the EU. In egg production the majority of commercial layers are kept in laying cages. There is wide variation in space allowance per bird from 300 to 400 cm in Brazil, Ukraine and India towards the current minimum of 550 cm(2) per hen in the EU. After 2012, hens in the EU will be kept in enriched cages with a minimum space allowance of 750 cm(2) per hen. It is expected that this will have an impact on world trade in egg products and especially egg powder. Trade in table eggs will continue to be limited to the local region. The EU is considering the use of labelling to provide consumers with more information concerning the standard of production. Another option could be to use financial mechanisms such as taxes or tariffs to prevent imports from other countries with lower standards. The likelihood of a measure being challenged would depend on how difficult it was for exporters outside the EU to meet the requirements
The future of the Dutch egg processing industry
This research examines the competitiveness of the Dutch egg products industry, as well as the consequences of tightening up the laws concerning layer poultry on the competitive position of the Dutch egg production industry. A tightening of the laws has, in fact, the effect of raising the production cost, and in this research the central question revolves around whether animal welfare-friendly egg products are perceived as products with added value by the buyers of egg products (mainly industrial buyers) and will thus also be offered for sale at a higher price. Furthermore, it will be investigated what the probable developmental directions are in the egg products industry if this higher price cannot be realised.Livestock Production/Industries,
Effect of Larval Nutrition on Maternal mRNA Contribution to the Drosophila Egg.
Embryonic development begins under the control of maternal gene products, mRNAs and proteins that the mother deposits into the egg; the zygotic genome is activated some time later. Maternal control of early development is conserved across metazoans. Gene products contributed by mothers are critical to many early developmental processes, and set up trajectories for the rest of development. Maternal deposition of these factors is an often-overlooked aspect of parental investment. If the mother experiences challenging environmental conditions, such as poor nutrition, previous studies in Drosophila melanogaster have demonstrated a plastic response wherein these mothers may produce larger eggs to buffer the offspring against the same difficult environment. This additional investment can produce offspring that are more fit in the challenging environment. With this study, we ask whether D. melanogaster mothers who experience poor nutrition during their own development change their gene product contribution to the egg. We perform mRNA-Seq on eggs at a stage where all mRNAs are maternally derived, from mothers with different degrees of nutritional limitation. We find that nutritional limitation produces similar transcript changes at all degrees of limitation tested. Genes that have lower transcript abundance in nutritionally limited mothers are those involved in translation, which is likely one of the most energetically costly processes occurring in the early embryo. We find an increase in transcripts for transport and localization of macromolecules, and for the electron transport chain. The eggs produced by nutrition-limited mothers show a plastic response in mRNA deposition, which may better prepare the future embryo for development in a nutrition-limited environment
Regulation of Op18 during Spindle Assembly in Xenopus Egg Extracts
Oncoprotein 18 (Op18) is a microtubule-destabilizing protein that is negatively regulated by phosphorylation. To evaluate the role of the three Op18 phosphorylation sites in Xenopus (Ser 16, 25, and 39), we added wild-type Op18, a nonphosphorylatable triple Ser to Ala mutant (Op18-AAA), and to mimic phosphorylation, a triple Ser to Glu mutant (Op18-EEE) to egg extracts and monitored spindle assembly. Op18-AAA dramatically decreased microtubule length and density, while Op18-EEE did not significantly affect spindle microtubules. Affinity chromatography with these proteins revealed that the microtubule-destabilizing activity correlated with the ability of Op18 to bind tubulin. Since hyperphosphorylation of Op18 is observed upon addition of mitotic chromatin to extracts, we reasoned that chromatin-associated proteins might play a role in Op18 regulation. We have performed a preliminary characterization of the chromatin proteins recruited to DNA beads, and identified the Xenopus polo-like kinase Plx1 as a chromatin-associated kinase that regulates Op18 phosphorylation. Depletion of Plx1 inhibits chromatin-induced Op18 hyperphosphorylation and spindle assembly in extracts. Therefore, Plx1 may promote microtubule stabilization and spindle assembly by inhibiting Op18
A genomic analysis and transcriptomic atlas of gene expression in Psoroptes ovis reveals feeding- and stage-specific patterns of allergen expression
Background: Psoroptic mange, caused by infestation with the ectoparasitic mite, Psoroptes ovis, is highly contagious, resulting in intense pruritus and represents a major welfare and economic concern for the livestock industry Worldwide. Control relies on injectable endectocides and organophosphate dips, but concerns over residues, environmental contamination, and the development of resistance threaten the sustainability of this approach, highlighting interest in alternative control methods. However, development of vaccines and identification of chemotherapeutic targets is hampered by the lack of P. ovis transcriptomic and genomic resources.
Results: Building on the recent publication of the P. ovis draft genome, here we present a genomic analysis and transcriptomic atlas of gene expression in P. ovis revealing feeding- and stage-specific patterns of gene expression, including novel multigene families and allergens. Network-based clustering revealed 14 gene clusters demonstrating either single- or multi-stage specific gene expression patterns, with 3075 female-specific, 890 male-specific and 112, 217 and 526 transcripts showing larval, protonymph and tritonymph specific-expression, respectively. Detailed analysis of P. ovis allergens revealed stage-specific patterns of allergen gene expression, many of which were also enriched in "fed" mites and tritonymphs, highlighting an important feeding-related allergenicity in this developmental stage. Pair-wise analysis of differential expression between life-cycle stages identified patterns of sex-biased gene expression and also identified novel P. ovis multigene families including known allergens and novel genes with high levels of stage-specific expression.
Conclusions: The genomic and transcriptomic atlas described here represents a unique resource for the acarid-research community, whilst the OrcAE platform makes this freely available, facilitating further community-led curation of the draft P. ovis genome
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