58 research outputs found
Organic selenium supplementation increased selenium concentrations in ewe and newborn lamb blood and in slaughter lamb meat compared to inorganic selenium supplementation
Background
Selenium is part of the antioxidant defence system in animals and humans. The available selenium concentration in soil is low in many regions of the world. The purpose of this study was to evaluate the effect of organic versus inorganic selenium supplementation on selenium status of ewes, their lambs, and slaughter lambs.
Methods
Ewes on four organic farms were allocated five or six to 18 pens. The ewes were given either 20 mg/kg inorganic selenium as sodium selenite or organic selenium as selenized nonviable yeast supplementation for the two last months of pregnancy. Stipulated selenium concentrations in the rations were below 0.40 mg/kg dry matter. In addition 20 male lambs were given supplements from November until they were slaughtered in March. Silage, hay, concentrates, and individual ewe blood samples were taken before and after the mineral supplementation period, and blood samples were taken from the newborn lambs. Blood samples from ewes and lambs in the same pens were pooled. Muscle samples were taken from slaughter lambs in March. Selenium concentrations were determined by atomic absorption spectrometry with a hydride generator system. In the ANOVA model, selenium concentration was the continuous response variable, and selenium source and farm were the nominal effect variables. Two-sample t-test was used to compare selenium concentrations in muscle samples from the slaughtered lambs that received either organic or inorganic selenium supplements.
Results
In all ewe pens the whole blood selenium concentrations increased during the experimental period. In addition, ewe pens that received organic selenium had significantly higher whole blood selenium concentrations (mean 0.28 μg/g) than ewe pens that received inorganic selenium (mean 0.24 μg/g). Most prominent, however, was the difference in their lambs; whole blood mean selenium concentration in lambs from mothers that received organic selenium (mean 0.27 μg/g) was 30% higher than in lambs from mothers that received inorganic selenium (mean 0.21 μg/g). Slaughter lambs that received organic selenium had 50% higher meat selenium concentrations (mean 0.12 mg/kg wet weight) than lambs that received inorganic selenium (mean 0.08 mg/kg wet weight).
Conclusion
Organic selenium supplementation gave higher selenium concentration in ewe and newborn lamb blood and slaughter lamb meat than inorganic selenium supplementation
Sediment source fingerprinting: benchmarking recent outputs, remaining challenges and emerging themes
Abstract: Purpose: This review of sediment source fingerprinting assesses the current state-of-the-art, remaining challenges and emerging themes. It combines inputs from international scientists either with track records in the approach or with expertise relevant to progressing the science. Methods: Web of Science and Google Scholar were used to review published papers spanning the period 2013–2019, inclusive, to confirm publication trends in quantities of papers by study area country and the types of tracers used. The most recent (2018–2019, inclusive) papers were also benchmarked using a methodological decision-tree published in 2017. Scope: Areas requiring further research and international consensus on methodological detail are reviewed, and these comprise spatial variability in tracers and corresponding sampling implications for end-members, temporal variability in tracers and sampling implications for end-members and target sediment, tracer conservation and knowledge-based pre-selection, the physico-chemical basis for source discrimination and dissemination of fingerprinting results to stakeholders. Emerging themes are also discussed: novel tracers, concentration-dependence for biomarkers, combining sediment fingerprinting and age-dating, applications to sediment-bound pollutants, incorporation of supportive spatial information to augment discrimination and modelling, aeolian sediment source fingerprinting, integration with process-based models and development of open-access software tools for data processing. Conclusions: The popularity of sediment source fingerprinting continues on an upward trend globally, but with this growth comes issues surrounding lack of standardisation and procedural diversity. Nonetheless, the last 2 years have also evidenced growing uptake of critical requirements for robust applications and this review is intended to signpost investigators, both old and new, towards these benchmarks and remaining research challenges for, and emerging options for different applications of, the fingerprinting approach
Environmental \u3ci\u3eSalmonella\u3c/i\u3e in Agricultural Fair Poultry Exhibits in Colorado
Salmonella enterica is a common zoonotic pathogen in humans. Transmission typically occurs through consumption of contaminated food products or contact with infected animals, including poultry or their environment. The objective of this study was to estimate the frequency of Salmonella contamination in the environment in poultry exhibits at agricultural fairs. Samples were collected from cages, feed, floors and tables in the exhibit and cultured for Salmonella. At least one environmental sample was positive for Salmonella in 10 of 11 fairs (91%), and Salmonella was isolated from 28 of 55 environmental samples (50.9%). Eleven different serotypes were detected. Results of this study demonstrate that environmental surfaces at agricultural fairs can be contaminated with Salmonella and could potentially serve as a route of transmission to bird owners and the general public. Poultry owners and the general public should be educated about the risks of Salmonella infection from the poultry exhibit environment. Agricultural fairs should consider instituting policies and practices to improve hygiene and mitigate the risk of zoonotic salmonellosis
Enhanced Biopharmaceutical Performance of Rivaroxaban through Polymeric Amorphous Solid Dispersion
Rivaroxaban (RXB) is an orally active
direct inhibitor of the activated
serine protease Factor Xa, given as monotherapy in the treatment of
venous thromboembolism (VTE). It has been characterized <i>in
vitro</i> as a substrate for the active, nonsaturable efflux
via P-gp transporter, limiting its high permeability. Therefore, the
role of P-gp inhibiting polymers in enhancing the biopharmaceutical
performance of RXB by preparing polymeric amorphous solid dispersion
and subsequent improvement in solubility and permeability was investigated.
Initially, solubility parameter and Flory–Huggins interaction
parameter were determined for miscibility studies between drug and
polymers. Binary dispersions were prepared by dissolving drug with
polymers eudragit S100, eudragit L100, and soluplus in common solvent
(5% v/v water in tetrahydrofuran) using spray dryer. Prepared binary
dispersions were analyzed by differential scanning calorimetry (DSC),
microscopy, powder X-ray diffractometry (PXRD), Fourier transform
infrared spectroscopy (FTIR), dynamic vapor sorption (DVS), and solution
nuclear magnetic resonance (NMR) spectroscopy. Superior performance
of binary dispersions was observed upon dissolution and solubility
studies over micronized active pharmaceutical ingredient. Amorphous
solid dispersion (ASD) prepared with soluplus showed 10-fold increase
in apparent solubility and maintenance of supersaturation for 24 h
compared to the crystalline RXB. Further, pharmacokinetic study performed
in animals was in good correlation with the solubility data. Increases
of 5.7- and 6.7-fold were observed in AUC and C<sub>max</sub>, respectively,
for ASDs prepared with soluplus compared to those with crystalline
RXB. FTIR and NMR spectroscopy unveiled the involvement of N–H
group of RXB with CO group of polymers in intermolecular interactions.
The decreased drug efflux ratio was observed for ASDs prepared with
eudragit S100 and soluplus in Caco-2 transport study suggesting improvement
in the absorption of RXB. Hence, the present study demonstrates ASD
using soluplus as a promising formulation strategy for enhancing the
biopharmaceutical performance of RXB by increasing the solubility
and circumventing the P-gp activity
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