Organic C levels of Ap horizons in North German Pleistocene sands as influenced by climate,texture, and history of land‐use

We evaluated the contents of organic carbon (C_org) of Ap horizons from 11 North German study areas along a Southeast to Northwest precipitation gradient with respect to their general levels and as related to C : N ratio, soil texture (clay content), bulk soil density, climate, and historical land‐use since 1780. The focus was on sandy soils, with the largest group of samples originating from 308 km² of the Fuhrberg catchment north of Hannover/Lower Saxony. Data from loess areas were used for comparisons. Major aims were (1) to quantify current C_org stocks, (2) to provide data on site‐specific, steady‐state C_org levels in old arable soils, and (3) to identify the main controls of C_org levels in the studied sands. The mean C_org content in sandy, well‐drained, old Ap horizons (uplands, > 200 years under cultivation, near steady‐state) increased with precipitation from < 8 g kg^—1 in the dry eastern parts of the study area (530 mm year^—1, 8.3°C) to 25 g kg^—1 in the moist Northwest (825 mm year^—1, 8.4°C). The C_org levels in lowlands which have been drained for more than 40 years were approximately 3 g kg^—1 higher than those of uplands under a similar climate. The factor clay content had no predictive value because low contents were associated with high C_org levels. Large proportions of refractory organic matter in sands resulting from specific features of historical land‐use and soil development (calluna heathland, heath plaggen fertilization, podzolization) appeared to be the most probable reason for such high C_org levels. However, the high C_org levels of these old arable sites were still exceeded by those of younger arable areas formerly under continuos grassland. A chrono‐sequence suggested that a period of about 100 years is necessary until a new steady‐state C_org level is established after conversion of grassland into arable land. Elevated C_org levels in current Ap horizons were also found for former woodland and heathland soils. The main conclusion is that sands can contain a lot of stable organic matter, sometimes more than finer textured soils.     

First Isolation of a Rabid Bat Infected with European Bat Lyssavirus in Luxembourg

Rabid bats are regularly reported in Europe, especially in countries that have implemented a bat surveillance network. In May 2013, bat rabies was evidenced for the first time in Luxembourg (southern city of Differdange). The rabies virus, an EBLV‐1b strain, was diagnosed in a serotine bat that bit a 29‐year‐old male person while he was asleep. The man received rapidly a post‐exposure RABV treatment and was put under strict medical supervision.     

Influence of foam structure on the release kinetics of volatiles from espresso coffee prior to consumption

The relationship between the physical structure of espresso coffee foam, called crema, and the above-the-cup aroma release was studied. Espresso coffee samples were produced using the Nespresso extraction system. The samples were extracted with water with different levels of mineral content, which resulted in liquid phases with similar volatile profiles but foams with different structure properties. The structure parameters foam volume, foam drainage, and lamella film thickness at the foam surface were quantified using computer-assisted microscopic image analysis and a digital caliper. The above-the-cup volatile concentration was measured online by using PTR-MS and headspace sampling. A correlation study was done between crema structure parameters and above-the-cup volatile concentration. In the first 2.5 min after the start of the coffee extraction, the presence of foam induced an increase of concentration of selected volatile markers, independently if the crema was of high or low stability. At times longer than 2.5 min, the aroma marker concentration depends on both the stability of the crema and the volatility of the specific aroma compounds. Mechanisms of above-the-cup volatile release involved gas bubble stability, evaporation, and diffusion. It was concluded that after the initial aroma burst (during the first 2-3 min after the beginning of extraction), for the present sample space a crema of high stability provides a stronger aroma barrier over several minutes.     

Characteristics of Gas Generation (NH3, CH4, N2O, CO2, H2O) From Horse Manure Added to Different Bedding Materials Used in Deep Litter Bedding Systems

The aim of this study was to analyze the influence of horse manure added to different bedding materials on the generation of gases (ammonia (NH₃), nitrous oxide, carbon dioxide, methane, water vapor) from deep litter bedding under standardized laboratory conditions. Two different types of straw (wheat and rye) and wood shavings were analyzed. The deep litter (substrate) was made of 25 kg of the respective bedding material, 60 kg horse feces, and 60 L ammonium chloride solution (urea), and spread out in identical chambers over 19 days (n = 3). On days 1, 8, 15, and 19, total nitrogen, total carbon, and dry matter content of the substrate, as well as the pH in 500-g samples, were measured along with. At the end of each test period, the nitrite nitrogen, nitrate nitrogen, and ammonium nitrogen contents of the leachate were analyzed. The wheat straw substrate emitted the highest concentration of NH₃ (4.31 mg/m³; P < .0001) and the wood shavings substrate emitted the lowest (1.73 mg/m³; P < .0001); the rye straw substrate generated 3.05 mg/m³. In addition, significant differences occurred during days 1 to 3 with respect to the generation of the gases NH₃, methane, nitrous oxide, carbon dioxide, and water vapor, and after the opening of the chamber on day 15. The nitrogen losses through the leachate occurred mainly in the form of nitrate, where the leachate from the wheat straw substrate had a significantly higher amount of nitrate nitrogen (44.56 mg) as compared with the leachates of the rye straw (14.49 mg; P ≤ .0001) and the wood shaving substrates (22.62 mg; P = .0010).     

In vivo staining of reduced iron by 2,2′ bipyridine in rice exposed to iron toxicity

A protocol for a novel method to visualize Fe(II) in rice tissues is proposed. The method is based on the selective formation of a purple‐red color complex of 2,2′ bipyridine and Fe(II). Rice genotypes were exposed to 18 mM Fe(II) in nutrient solution for 2 d. Root systems of intact plants were subsequently placed in 2,2′ bipyridine solutions. The formation of the [Fe(bipy)<$>_3^{2+}<$>] color complex was visualized using bifocal microscopy. The method may improve the selection of genotypes during breeding for Fe‐toxicity resistance of rice.     

Lactational traits of importance in dairy cows and applications for emerging biotechnologies

New molecular and quantitative genetic technologies are the latest in a long list of technologies that have been introduced to dairy industries over many decades to improve the performance of cows. The catalysts for future advances will be sequencing of the bovine genome and development of high-throughput technologies to identify and exploit relevant variation in DNA sequences. The new technologies will allow the selection of animals based on specific genotypes that suit specific applications such as once-daily (OAD) milking or extended lactation.

These technologies will also allow exploitation of between-cow variation in milk composition, which is currently hidden by bulking of milk on and between farms. Thus, there are opportunities to produce milk from herds of cows selected for specific milk composition that might be, for example, more suitable for cheese-making or have milkfat with specific properties to enhance human health. Identification of genes and gene polymorphisms associated with improved resistance to specific diseases in cows and other farm species also represents a real opportunity to improve animal health over the coming decade.

New levels of genetic regulation have been identified, e.g. microRNA and epigenetics, the impacts of which on the performance of cows and humans are only just beginning to be understood.

There is a potential role for veterinarians to provide or be the interface for provision of genetic advice to farmers in much the same way that nutritional advice is currently given.     

First evidence of Kunjin strain of West Nile virus associated with saltwater crocodile (Crocodylus porosus) skin lesions

Recently, the Kunjin strain of West Nile virus (WNV_KUN) has been detected using qRT‐PCR in belly skin lesions of farmed juvenile saltwater crocodiles. This follows an established association between similar lesions and West Nile virus in American alligators. The lesions present as cutaneous lymphohistiocytic aggregates in the dermal layers of both species. While these lesion do not create an obvious defect on the live crocodile, upon tanning the lesion area collapses and does not uptake the dye evenly, thus reducing its aesthetic appeal. As a result, skins are being rejected jeopardising the economic viability of the Australian crocodile industry. Over 50 skin lesions have since been confirmed as WNV_KUN‐positive and preliminary evidence of lesion restructuring is presented. Horizontal transmission of WNV_KUN by mosquitoes is well‐established but other transmission routes, such as ingestion and cloacal shedding, need further evaluation. An infection trial is currently underway to ensure WNV_KUN is the causative agent of these skin lesions.     

In vivo studies on the metabolism of the monoterpenes S-(+)- and R-(-)-carvone in humans using the metabolism of ingestion-correlated amounts (MICA) approach

The major in vivo metabolites of S-(+)- and R-(-)-carvone in a metabolism of ingestion correlated amounts (MICA) experiment were newly identified as alpha,4-dimethyl-5-oxo-3-cyclohexene-1-acetic acid (dihydrocarvonic acid), alpha-methylene-4-methyl-5-oxo-3-cyclohexene-1-acetic acid (carvonic acid), and 5-(1,2-dihydroxy-1-methylethyl)-2-methyl-2-cyclohexen-1-one (uroterpenolone) on the basis of mass spectral analysis in combination with syntheses and NMR experiments. Minor metabolites were identified as reduction products of carvone, namely, the alcohols carveol and dihydrocarveol. The previously identified major in vivo metabolite in rabbits, 10-hydroxycarvone, could not be detected, indicating either concentration effects or interspecies differences. Metabolic pathways for carvone in humans including oxidation of the double bond in the side chain and, to a minor extent 1,2- and 1,4 + 1,2-reduction of carvone, are discussed. No differences in metabolism between S-(+)- and R-(-)-carvone were detected.