How browsing by red deer impacts on litter decomposition in a native regenerating woodland in the Highlands of Scotland

Herbivores can indirectly affect ecosystem productivity and processes such as nutrient cycling and decomposition by altering the quantity and quality of resource inputs into the decomposer subsystem. Here, we tested how browsing by red deer impacts on the decomposition of, and nutrient loss from, birch leaf litter (Betula pubescens), and tested whether effects of browsing on these measures were direct, via alteration of the quality of leaf litter, or indirect through long term impacts of deer browsing on soil biological properties. This was tested in a microcosm experiment using soil and litter taken from inside and outside three individual fenced exclosures located at Creag Meagaidh National Nature Reserve, Scotland. We found that litter of un-browsed trees decomposed faster than that from browsed trees, irrespective of whether soil was sourced from inside or outside exclosures. These findings suggest that effects of browsing on litter quality, rather than on soil biological properties, are the key determinant of enhanced decomposition in un-browsed areas of this ecosystem. Despite this, we found no consistent impact of browsing on litter C:N, a key indicator of litter quality; however, the rate of litter decomposition was linearly and negatively related to litter C:N when analysed across all the sites, indicating that this measure, in part, contributed to variation in rates of decomposition in this ecosystem. Our findings indicate that herbivores impact negatively on rates of decomposition in this ecosystem, ultimately retarding nutrient cycling rates, and that these effects are, in part, related to changes in litter quality.     

Combining snow water equivalent data from multiple sources to estimate spatio-temporal trends and compare measurement systems

Owing to the importance of snowfall to water supplies in the western United States, governmentagencies regularly collect data on snow water equivalent (the amount of water in snow) over this region. Several differentmeasurementsystem, of possibly different levels of accuracy and reliability, are in operation: snow courses, snow telemetry, aerial markers, and airborne gamma radiation. Data are available at more than 2,000 distinct sites, dating back a variable number of years (in a few cases to 1910). Historically, these data have been used primarily to generate flood forecasts, and short-term (intra-annual) predictions of streamflow and water supply. However, they also have potential for addressing the possible effects of long-term climate change on snowpack accumulations and seasonal water supplies. We presenta Bayesian spatio-temporalanalysis of the combined snow water equivalent (SWE) data from all four systems that all ows for systematic differences in accuracy and reliability. The primary objectives of our analysis are (1) to estimate the long-term temporal trend in SWE over the western U.S. and characterizehow this trend variesspatially, with quantifiable estimates of variability, and (2) to investigate whether there are systematic differences in the accuracy and reliability of the four measurement systems. We find substantial evidence of a decreasing temporal trend in SWE in the Pacific North west and northern Rockies, but no evidence of a trend in the intermountain region and southern Rockies. Our analysis also indicates that some of the systems differ significantly with respect to their accuracy and reliability.     

Long-term avian research at the San Joaquin Experimental Range: Recommendations for monitoring and managing oak woodlands

Experimental forests and ranges are living laboratories that provide opportunities for conducting scientific research and transferring research results to partners and stakeholders. They are invaluable for their long-term data and capacity to foster collaborative, interdisciplinary research. The San Joaquin Experimental Range (SJER) was established to develop appropriate land management practices on foothill rangelands in California. SJER has a long and rich history of avian research. Natural history observations recorded since 1935 demonstrate that oak woodlands are one of the most diverse habitat types in North America. Early avian studies focused on California quail (Callipepla californica) as a game species and led to insights on quail diet and habitat requirements. Starting in the late 1970s, the focus of avian research shifted to methods for detecting changes in wildlife populations over time and response to management practices. This research has led to important recommendations for implementing bird monitoring programs. Using data collected on bird numbers, in conjunction with monitoring reproductive success of all species, recent studies have examined life history strategies, source-sink dynamics, the effects of livestock grazing, and the impacts of an invasive species on native cavity-nesting species. We are currently in the process of examining population trends and predicting the effects of climate change using long-term data. SJER continues to provide unique opportunities for research and educational activities that increase our understanding of the foothill oak woodlands of California.     

Formulation and Characterization of Drug‐Loaded Microparticles Using Distillers Dried Grain Kafirin

Kafirin, a protein extracted from sorghum grain, has been formulated into microparticles and proposed for use as a delivery system owing to the resistance of kafirin to upper gastrointestinal digestion. However, extracting kafirin from sorghum distillers dried grains with solubles (DDGS) may be more efficient, because the carbohydrate component has been removed by fermentation. This study investigated the properties and use of kafirin extracted from DDGS to formulate microparticles. Prednisolone, an anti‐inflammatory drug that could benefit from a delayed and targeted delivery system to the colon, was loaded into DDGS kafirin microparticles by phase separation with sodium chloride. Scanning electron micrographs revealed that the empty and prednisolone‐loaded microparticles were round in shape and varied in size. Surface binding studies indicated prednisolone was loaded within the microparticles rather than being solely bound on the surface. These findings demonstrate DDGS kafirin can be formulated into microparticles and loaded with medication. Future studies could investigate the potential applications of DDGS kafirin microparticles as an orally administered targeted drug‐delivery system.     

Review of irrigation system performance with respect to initial objectives

This paper presents the results of assessment studies of the performance of gravity irrigation projects, in six countries in different climate and social environments, with respect to their original objectives in terms of water availability, water use efficiencies, equity of water distribution, cropping intensity and crop yields, and project economic rates of return.An important lesson is the need for more realistic assumptions in the adoption of design standards, especially irrigation efficiency which affect the cropping intensity, the overall productivity of the project and its economic viability. This comparative method of performance assessment applied to a variety of projects has also provided some useful insights into the relative value of the different approaches to design of gravity irrigation systems.The views expressed in this paper are those of the author and are not presented as official views of the World Bank.     

Comparison of 2 glucose analytical methodologies in immature Kemp’s ridley sea turtles: dry chemistry of plasma versus point-of-care glucometer analysis of whole blood

Blood glucose measurements provide important diagnostic information regarding stress, disease, and nutritional status. Glucose analytical methodologies include dry chemistry analysis (DCA) of plasma and point-of-care (POC) glucometer analysis of whole blood; however, these 2 methods differ in cost, required sample volume, and processing time. Because POC glucometers use built-in equations based on features of mammalian blood to convert whole blood measurements to plasma equivalent units, obtained glucose data must be compared and validated using gold-standard chemistry analytical methodology in reptiles. For in-water, trawl-captured, immature Kemp’s ridley sea turtles (Lepidochelys kempii) from Georgia, USA, we observed significant, positive agreement between the 2 glucose determination methods; however, the glucometer overestimated glucose concentrations by 1.4 mmol/L on average in comparison to DCA and produced a wider range of results. The discordance of these results suggests that POC glucometer glucose data should be interpreted in the context of methodology- and brand-specific reference intervals along with concurrent packed cell volume data.     

Nutrient–drug interactions in nutritional support

Abstract Objective: To review the types and potential consequences of diet/nutrient–drug interactions that can occur in patients receiving nutritional support. Data sources: A literature review was performed using Ovid multi‐database searching including Medline, Agricola and Biosis. Summary: Although very little information is currently available that pertains specifically to veterinary patients, we know from the human experience that food intake and diet composition can affect the absorption, distribution, metabolism, efficacy and toxicity of a drug. Conversely, certain drugs can alter the absorption of nutrients when administered in conjunction with food or act to antagonize nutrient metabolism or function. The different ways that incompatibility can arise between food or nutrients and drugs in patients receiving nutritional support and strategies for avoiding these problems are discussed. Conclusions: The consequences of diet/nutrient–drug interactions include decreased tolerance of nutritional support, loss of feeding access, decreased drug efficacy, nutrient malabsorption or malassimilation, and risk of drug overdosage. Therefore, when patients receiving nutritional support experience these types of complications, a review of the diet, route of nutritional support, drugs, and timing of feeding and medication administration are indicated.