ASVCP quality assurance guidelines: external quality assessment and comparative testing for reference and in‐clinic laboratories

The purpose of this document is to educate providers of veterinary laboratory diagnostic testing in any setting about comparative testing. These guidelines will define, explain, and illustrate the importance of a multi‐faceted laboratory quality management program which includes comparative testing. The guidelines will provide suggestions for implementation of such testing, including which samples should be tested, frequency of testing, and recommendations for result interpretation. Examples and a list of vendors and manufacturers supplying control materials and services to veterinary laboratories are also included.     

Amaranth (Amaranthus hypochondriacus) as an alternative crop for sustainable food production: Phenolic acids and flavonoids with potential impact on its nutraceutical quality

The demand for food is increasing, not only to meet food security for growing populations, but also to provide more nutritious food, rich in good quality proteins and nutraceutical compounds. The amaranth (Amaranthus hypochondriacus) plant, in addition to its high nutritive and nutraceutical characteristics, has excellent agronomic features. The objective of the present study was to analyze some physical and proximal-nutritional properties of amaranth seeds obtained from different varieties grown in arid zones and characterize their phenolic acids and flavonoids. Two commercial (Tulyehualco and Nutrisol) and two new (DGETA and Gabriela) varieties of A. hypochondriacus were grown at the Mexican Highlands zone. Tulyehualco and DGETA varieties had higher seed yield of 1475 and 1422 kg ha⁻¹, respectively, comparable to corn and soybean production in agricultural areas. Gabriela had the highest protein content of 17.3%, but all varieties had an adequate balance of essential amino acids. Polyphenols as rutin (4.0–10.2 μg g⁻¹ flour) and nicotiflorin (7.2–4.8 μg g⁻¹ flour) were detected. Amaranth can be cultivated in arid zones where commercial crops cannot be grown; the seeds besides their well known nutritive characteristics could be a source of phenolic compounds of high antioxidant properties.     

Influence of surfactants on the leaching of bentazone in a sandy loam soil

BACKGROUND: Surfactants are very often used for more efficient pesticide spraying, but knowledge about their influence on the leaching potential for pesticides is very limited. In the present study, the leaching of the herbicide bentazone [3‐isopropyl‐1H‐2, 1,3‐benzothiadiazin‐4(3H)‐one 2,2‐dioxide] was measured in columns with sandy loam soil with or without the addition of a non‐ionic surfactant, octylphenol ethylene oxide condensate (Triton X‐100, Triton), and an anionic surfactant, sodium dodecylbenzenesulfonate (SDBS), and in the presence of both surfactants (SDBS + Triton). RESULTS: The mobility of bentazone (B) increased in the following order: B + Triton (slowest) < B + SDBS + Triton < B < B + SDBS (fastest). When Triton X‐100 was applied to the soil together with bentazone, the leaching of bentazone in the soil decreased significantly compared with leaching of bentazone without the addition of surfactant. SDBS and Triton X‐100 neutralised their influence on the leaching speed of bentazone in the soil columns when both surfactants were applied with bentazone. CONCLUSION: From the study it can be concluded that, depending on their properties, surfactants can enhance or reduce the mobility of bentazone. By choosing a non‐ionic surfactant, bentazone mobility can be reduced, giving time for degradation and thereby reducing the risk of groundwater pollution. Copyright © 2009 Society of Chemical Industry     

Sensor‐based assessment of herbicide effects

Non‐destructive assessment of herbicide effects may be able to support integrated weed management. To test whether effects of herbicides on canopy variables could be detected by sensors, two crops were used as models and treated with herbicides at BBCH 20 using a logarithmic sprayer. Twelve days after spraying at BBCH 25 and 42 days after sowing, nine sensor systems scanned a spring barley and an oilseed rape field experiment sown at different densities and sprayed with increasing field rates of glyphosate and tribenuron‐methyl. The objective was to compare ED₅₀s for crops and weeds derived by the different sensors in relation to crop density and herbicides. Although sensors were not directly developed to detect herbicide symptoms, they all detected changes in canopy colours or height and crop density. Generally ED₅₀s showed the same pattern in response to crop density within herbicide, but there were marked differences between barley and oilseed rape. We suggest that the results of comparing the various sensor outputs could become a stepping stone to future standardisation for the benefit of the research and development of sensors that will detect herbicide effect on crops and weeds, particularly at the most vulnerable stages of development of the canopy.     

Sudden change in long‐term ocean climate fluctuations corresponds with ecosystem alterations and reduced recruitment in Norwegian spring‐spawning herring (Clupea harengus,Clupeidae)

Fish stocks vary in abundance. The causes behind the fluctuations may be difficult to determine, especially ones caused by natural fluctuations, but long‐term data series may provide indications of the mechanisms. Assessments show that the recruitment to the Norwegian spring‐spawning herring (Clupea harengus, Clupeidae) has remained low since 2004, a year which produced the last really rich year‐class. Long time‐series of estimated recruitment and mean winter temperature in the ocean showed a significant positive correlation for the period 1921–2004. Here, we show that this positive correlation did not continue from 2005 onwards as the winter temperature increased to high levels while herring recruitment decreased and has remained low. The density of zooplankton in the drift route of the herring larvae dropped significantly after 2004, and their centre of gravity shifted northwards. There may currently be heavy predation on the larvae by Atlanic mackerel (Scomber scombrus, Scombridae), and top‐down regulation is suggested to hamper successful recruitment. Our analysis indicates that the presence of food and overlap with high food concentrations are likely important regulators of survival in herring larvae. The findings may be important for future management and planning of fisheries of this stock because recruitment failure may continue if temperature remains high and food abundance remains low.     

Bioactive benzoxazinoids in rye bread are absorbed and metabolized in pigs

Recently, bioactive benzoxazinoids were discovered in cereal grains and bakery products. In this study, we studied the uptake, distribution, and metabolism of these secondary metabolites using a pig model. Twelve benzoxazinoid compounds and their 4 transformation products were quantified in the pigs' diets and biofluids using high-performance liquid chromatography coupled to electrospray ionization triple quadrupole mass spectrometry. The 2-β-D-glucopyranosyloxy-4-hydroxy-1,4-benzoxazin-3-one (DIBOA-glc) was the most dominant benzoxazinoid (232 nmol/g DM) seconded by the double-hexose derivative of DIBOA (provisionally characterized here as DIBOA-glc-hex) in the rye-based diet. DIBOA-glc (derived from the diet and intestinal deglycosylation of DIBOA-glc-hex) was apparently reduced to 2-β-D-glucopyranosyloxy-1,4-benzoxazin-3-one (HBOA-glc), the most dominant benzoxazinoid in the blood (829 nmol/L). The benzoxazinoid compounds were excreted in the urine, with HBOA-glc (18 μmol/L) as a major metabolite. In this study, we determined for the first time the bioavailability of dietary benzoxazinoids that have high digestibility, distribution, and metabolism in mammals. These findings could be a milestone for the exploitation of healthful and pharmacological properties of benzoxazinoids.     

Competition Affects the Production of First Backcross Offspring on F1-hybrids, Brassica Napus × B. Rapa

Summary Interspecific F₁-hybrids may arise in fields with transplastomic oilseed rape where B. rapa occurs as a weed. Spilled seeds, including transplastomic F₁-hybrids with B. rapa, may germinate, which creates an opportunity for production of transplastomic BC₁ with B. rapa as father (BC_1r). Field trials were made with three different proportions of B. napus, B. rapa and F₁-hybrids and three different densities. Contrary to most studies on how plant competition affects introgression between oilseed rape and B. rapa, this study focused on offspring produced on F₁-hybrids, where the F₁-hybrids had oilseed rape as maternal parent. We estimated the BC_1r production in all combinations of proportion and density, and found that B. rapa sired from 0.6–7.8% of the offspring. At the proportion with the highest abundance of F₁-hybrids the entire paternity was assessed. There was a significant density effect on the production of BC_1r but the effect differed among proportions. Both the highest and lowest frequencies of BC_1r were obtained at high plant density. Neither the proportion nor density affected the number of BC_1r per square-meter significantly. Biomass components decreased significantly from low to intermediate density, whereas a further increase in density only affected the thousand-seed weight significantly. On the basis of the results from the present experiment we conclude that introgression of transgenes from transplastomic oilseed rape to B. rapa seems most likely at current field densities of B. napus, and when B. rapa is an abundant weed.     

Contaminant aspects of blackish surface deposits on highway roadsides

A blackish, sandy material (‘blackish deposit’, BD) accumulates on highway roadsides. Few years after road opening it may reach several centimeters of depth. Comparison of BD rates of accumulation with reported loads of suspended solids in highway runoff suggests blackish deposits to originate both from suspended solids in road runoff and from aerial depositions. This study of four Danish highways shows that BD is considerably different from the original surface (OS) material. Compared to OS-materials, BD-materials are clearly darker, contain more organic matter(4–8% versus around 1% in OS), have a high and less-variable content of clay and metal oxides, and a slightly lower bulk weight and pH. Similar clay mineralogy points to both BD and OS to be of local origin. Both materials contain lime (calcite). The textural border between BD and OS is also a sharp border between different levels of soil contamination: Zn up to 330 mg/kg in BD versus 19–63 mg/kg in OS, Pb up to 210 mg/kg versus 5–33 mg/kg, Cr up to 250 mg/kg versus 3–10 mg/kg, Cd up to twice as high in BD as in OS, Br and As markedly higher in BD than OS, heavy mineral oils (nC25–nC35) up to 680 mg/kg versus 16–24 mg/kg, and sum of PAH up to 1.4 mg/kg versus < 0.05–0.72 mg/kg. The continuous deposition of organic matter, calcite, metal oxides and clay suggest that BD, in addition to particles, is able to accumulate dissolved contaminants from infiltrating road runoff.