Causes of mortality in laying hens in different housing systems in 2001 to 2004

<p>Abstract</p> <p>Background</p> <p>The husbandry systems for laying hens were changed in Sweden during the years 2001 – 2004, and an increase in the number of submissions for necropsy from laying hen farms was noted. Hence, this study was initiated to compare causes of mortality in different housing systems for commercial laying hens during this change.</p> <p>Methods</p> <p>Based on results from routine necropsies of 914 laying hens performed at the National Veterinary Institute (SVA) in Uppsala, Sweden between 2001 and 2004, a retrospective study on the occurrence of diseases and cannibalism, i.e., pecking leading to mortality, in different housing systems was carried out. Using the number of disease outbreaks in caged flocks as the baseline, the expected number of flocks with a certain category of disease in the other housing systems was estimated having regard to the total number of birds in the population. Whether the actual number of flocks significantly exceeded the expected number was determined using a Poisson distribution for the variance of the baseline number, a continuity correction and the exact value for the Poisson distribution function in Excel 2000.</p> <p>Results</p> <p>Common causes of mortality in necropsied laying hens included colibacillosis, erysipelas, coccidiosis, red mite infestation, lymphoid leukosis and cannibalism. Less common diagnoses were Newcastle Disease, pasteurellosis and botulism. Considering the size of the populations in the different housing systems, a larger proportion of laying hens than expected was submitted for necropsy from litter-based systems and free range production compared to hens in cages (<it>P </it>< 0.001). The study showed a significantly higher occurrence of bacterial and parasitic diseases and cannibalism in laying hens kept in litter-based housing systems and free-range systems than in hens kept in cages (<it>P </it>< 0.001). The occurrence of viral diseases was significantly higher in indoor litter-based housing systems than in cages (<it>P </it>< 0.001).</p> <p>Conclusion</p> <p>The results of the present study indicated that during 2001–2004 laying hens housed in litter-based housing systems, with or without access to outdoor areas, were at higher risk of infectious diseases and cannibalistic behaviour compared to laying hens in cages. Future research should focus on finding suitable prophylactic measures, including efficient biosecurity routines, to reduce the risk of infectious diseases and cannibalism in litter-based housing systems for laying hens.</p

Transgenesis in Animal Agriculture: Addressing Animal Health and Welfare Concerns

The US Food and Drug Administration’s final Guidance for Industry on the regulation of transgenesis in animal agriculture has paved the way for the commercialization of genetically engineered (GE) farm animals. The production-related diseases associated with extant breeding technologies are reviewed, as well as the predictable welfare consequences of continued emphasis on prolificacy at the potential expense of physical fitness. Areas in which biotechnology could be used to improve the welfare of animals while maintaining profitability are explored along with regulatory schema to improve agency integration in GE animal oversight

Stiffening Performance of Cold-Formed C-Section Beam Filled with Lightweight-Recycled Concrete Mixture

The aim of this paper is to investigate the flexural performance of a new steel–concrete composite beam system, which is required to carry higher loads when applied in flooring systems with less self-weight and cost compared with conventional composite beams. This new composite member is prepared by filling a single cold-formed steel C-section with concrete material that has varied lightweight-recycled aggregates. In addition, varied stiffening scenarios are suggested to improve the composite behavior of this member, since these cold-formed C-sections are of a slender cross-section and more likely to buckle and twist under high bending loads than those of hot-rolled C-sections. The influence of using four different lightweight-recycled aggregates that combine together in the infill concrete material was investigated. These recycled aggregates are recycled concrete aggregate (RCA), expanded polystyrene (EPS) beads, crumb rubber aggregates (CRA) and fine glass aggregates (FGA). For this purpose, 14 samples of cold-formed galvanized steel C-purlin were filled with concrete material (containing 0 to 100% recycled aggregates) which are experimentally tested under pure bending load, and 1 additional sample was tested without the filling material. Further numerical models were prepared and analyzed using finite element analysis software to investigate the effects of additional parameters that were not experimentally examined. Generally, the results confirm that filling the C-sections with concrete material that contains varied percentages of recycled aggregates offer significantly improved the flexural stiffness, bending capacity, and ductility performances. For example, using infill concrete materials with 0% and 100% recycled aggregate replacement increased the bending capacity of hollow C-section by about 11.4 and 8.6 times, respectively. Furthermore, stiffening of the concrete-filled C-sections with steel strips or screw connectors eventually improved the composite behavior of the specimens which led to an increase in their bending capacities accordingly, and this improvement enhanced more with an increased number of these strips and connectors.</jats:p

WTa37O95.487 Nanocatalyst for Pollutant Degradation

This is the author accepted manuscript. The final version is available from the American Chemical Society via the DOI in this recordData Availability: The data that support the findings of this study are available from the corresponding author upon reasonable request.The release of toxic industrial effluents has created serious impacts on human health and the aquatic ecosystem. WTa37O95.487 is a wide-band gap material that was reported in 1971, but no one has investigated its photocatalytic properties due to its wide band gap and unique crystal structure. Herein, we carried out detailed experimental and density functional theory (DFT) simulations of WTa37O95.487 nanocatalysts. The influence of temperature and light intensity on their crystallography, morphology, optical, and photocatalytic properties was studied. The powder obtained at 150 °C (WT-1) exhibited higher photocatalytic activity of 99% of methylene blue dye degradation within 30 min with a pseudo-first-order kinetics constant of 0.0643 min–1. DFT simulations revealed a good correlation between theory and experiment of electronic properties of WTa37O95.487, which consequently validate the catalytic performance of the catalyst. The WTa37O95.487 nanocatalyst is proposed as a novel and effective photocatalyst for treating dye effluents of wastewater.National University of MalaysiaCenter for Research and Instrumentation (CRIM)Engineering and Physical Sciences Research Council (EPSRC

Multifaceted role of tocotrienols in cardioprotection supports their structure: function relation

Tocotrienols are a class of vitamin E which modulates several mechanisms associated with cardioprotection, anti-cancer, anti-diabetic, and neuroprotection. Unlike other Vitamin E-like compounds, tocotrienols possess inimitable properties. Quite a lot of studies have determined the cardioprotective abilities of tocotrienols and have been shown to possess novel hypocholesterolemic effects together with an ability to reduce the atherogenic apolipoprotein and lipoprotein plasma levels. In addition, tocotrienol has been suggested to have an antioxidant, anti-thrombotic, and anti-tumor effect indicating that tocotrienol may serve as an effective agent in the prevention and/or treatment of cardiovascular disease and cancer. The bioactivity exhibited is due to the structural characteristics of tocotrienols. Rich sources of tocotrienols which include rice bran, palm oil, and other edible oils exhibit protective effect against cardiovascular disorders. The conclusions drawn from the early literature that vitamin E group of compounds provides an inevitable role in cardioprotection is sustained in many more recent studies