Phosphorus forms and enzymatic hydrolyzability of organic phosphorus in soils after 30 years of organic and conventional farming

Lower P‐input levels in organic than conventional farming can decrease soil total and available P, which can potentially be resupplied from soil organic P. We studied the effect of 30 y of conventional and organic farming on soil P forms, focussing especially on organic P. Soil samples (0–20 cm) were taken in a field experiment with a nonfertilized control, two organic systems receiving P inputs as animal manure, and two conventional systems receiving only mineral P or mineral P and manure. Soils were analyzed for total, inorganic, organic, and microbial P, by sequential P fractionation and by enzyme additions to alkaline soil extracts. Samples taken prior to starting the experiment were also analyzed. Average annual P balances ranged from –20 to +5 kg ha^–1. For systems with a negative balance, labile and moderately labile inorganic P fractions decreased, while organic and stable inorganic P fractions were hardly affected. Similar quantities and proportions of organic P extracted with NaOH‐EDTA were hydrolyzed in all soils after addition of an acid phosphatase, a nuclease, and a phytase, and enzyme‐stable organic P was also similar among soils. Thus, neither sequential fractionation nor enzyme addition to alkaline soil extracts showed an effect of the type of applied P (manure vs. mineral) on organic P, suggesting that organic P from manure has largely been mineralized. Thus far, we have no indication that the greater microbial activity of the organic systems resulted in a use of stable P forms.     

Antinociceptive and anti-inflammatory activity from algae of the genus Caulerpa

Marine natural products have been the focus of discovery for new products of chemical and pharmacological interest. The aim of this study was to evaluate the antinociceptive activity of the methanolic (ME), acetate (AE), hexanic (HE) and chloroform (CE) extracts obtained from Caulerpa mexicana, and ME, CE and HE obtained from Caulerpa sertularioides. These marine algae are found all over the world, mainly in tropical regions. Models such as the writhing test, the hot plate test and formalin-induced nociception test were used to evaluate antinociceptive activity in laboratory mice. In the writhing test, all the extracts were administered orally at a concentration of 100 mg/kg, and induced high peripheral antinociceptive activity, with a reduction in the nociception induced by acetic acid above 65%. In the hot plate test, treatment with extracts from C. sertularioides (100 mg/kg, p.o.) did not significantly increase the latency of response, although the ME, AE and HE from C. mexicana showed activity in this model. This result suggests that these extracts exhibit antinociceptive activity. In the formalin test, it was observed that ME, AE and HE obtained from C. mexicana reduced the effects of formalin in both phases. On the other hand only CE from C. sertularioides induced significant inhibition of the nociceptive response in the first phase. To better assess the potential anti-inflammatory activity of the extracts, the carrageenan-induced peritonitis test was used to test Caulerpa spp. extracts on cell migration into the peritoneal cavity. In this assay, all extracts evaluated were able to significantly inhibit leukocyte migration into the peritoneal cavity in comparison with carrageenan. These data demonstrate that extracts from Caulerpa species elicit pronounced antinociceptive and anti-inflamatory activity against several nociception models. However, pharmacological and chemical studies are continuing in order to characterize the mechanism(s) responsible for the antinociceptive action and also to identify the active principles present in the Caulerpa species.     

Isolation of volatils from maritime pine sawdust waste by different processes: Ultrasound,microwave, turbohydrodistillation,and hydrodistillation

This study concerns the transformation of maritime pine (Pinus pinaster) sawdust waste into potentially novel products through isolation of volatile compounds in the form of valuable oil. Different techniques, namely, turbohydrodistillation (THD), solvent-free microwave extraction (SFME), microwave hydrodiffusion and gravity (MHG), and ultrasound-assisted extraction (UAE) were tested. These different processes were compared to conventional hydrodistillation (HD) and allowed to extract almost similar yields of isolated oils. THD which consists in a permanent agitation during extraction and UAE improve the kinetics of extraction, but MHG and SFME required the shortest extraction times, 60 min to reach a maximal yield of 0.272 and 0.266% (w/w), respectively. The compositions of isolated oils are almost similar with a high proportion of oxygenated compounds for MHG and SFME, respectively, 56.9% and 54.5% compared with 37.7%, 44.1% and 34.1%, respectively, for THD, UAE, and for the conventional HD method.     

Development and evaluation of an indirect enzyme-linked immunosorbent assay for serological detection of Schmallenberg virus antibodies in ruminants using whole virus antigen

Background

In late 2011, a new Orthobunyavirus of the Simbu serogroup named Schmallenberg virus (SBV) emerged in continental Europe. The virus is transmitted by hematophagous arthropods, with the Culicoides species as, so far known, main vectors. Infection with the virus can cause clinical signs in adult ruminants including diarrhea, fever and reduced milk production. Transplacental infection of the developing fetus can lead to malformations of varying severity. To assess seroprevalence of SBV in Sweden an indirect enzyme-linked immunosorbent assay (ELISA) was established in connection with the surveys. Here, we describe the development and evaluation of the indirect ELISA, based on whole virus as the coating antigen and a monoclonal antibody for the detection of antibodies to SBV in ruminant sera. The evaluation includes comparison between the in-house ELISA, virus neutralization test and an indirect commercial ELISA.

Results

The optimal working dilutions of antigens and conjugate were estimated with checkerboard titrations. Comparative studies, including ROC analyses, were used for the selection of an optimal cut-off (S/P value = sample value as percentage of positive control value). With an estimated S/P value of 15% the whole virus ELISA showed a specificity of 100% and a sensitivity of 99.19% compared to virus neutralization test (VNT) and with a good consistency as shown in reproducibility and variability experiments. Furthermore, the comparison of our whole virus indirect ELISA to an indirect ELISA with a SBV nucleoprotein antigen, demonstrated a higher sensitivity of our test.

Conclusion

The indirect whole virus ELISA described in this paper is a readily available test for serological analysis of SBV antibodies. Since this in-house ELISA demonstrates a specificity and sensitivity comparable to virus neutralization test and also shows a higher sensitivity compared to commercially available indirect ELISA, it is a useful alternative for surveillance and screening purposes of SBV.     

Biological activity of acetylated phenolic compounds

In recent years an effort has been made to isolate and identify biologically active compounds that are included in the Mediterranean diet. The existence of naturally occurring acetylated phenolics, as well as studies with synthetic ones, provide evidence that acetyl groups could be correlated with their biological activity. Platelet activating factor (PAF) is implicated in atherosclerosis, whereas its inhibitors seem to play a protective role against cardiovascular disease. The aim of this study was to examine the biological activity of resveratrol and tyrosol and their acetylated derivatives as inhibitors of PAF-induced washed rabbit platelet aggregation. Acetylation of resveratrol and tyrosol was performed, and separation was achieved by HPLC. Acetylated derivatives were identified by negative mass spectrometry. The data showed that tyrosol and its monoacetylated derivatives act as PAF inhibitors, whereas diacetylated derivatives induce platelet aggregation. Resveratrol and its mono- and triacetylated derivatives exert similar inhibitory activity, whereas the diacetylated ones are more potent inhibitors. In conclusion, acetylated phenolics exert the same or even higher antithrombotic activity compared to the biological activity of the initial one.     

Cattle cruelty and risks of meat contamination at Akinyele cattle market and slaughter slab in Oyo State,Nigeria

Cattle transported to the government-run cattle market and slaughter slab in Akinyele, Oyo State, Nigeria on their final voyage are facing a disturbingly cruel, filthy and unsafe environment that is also raising the risk of contamination of meat sold for human consumption. This report gives a picture of what the cattle have to go through before they are slaughtered. This study also reveals cattle awaiting slaughter in abysmal health conditions, cows pulled with extreme force towards lairage and slaughter slab. Equally disturbing is the filthy situation inside the abattoir where the risk of contamination of meat is significant. Also, poor meat handling, transportation and sales practices subject meat to contamination leading to poor quality and exposure of human consumers to health risk. Development of hygienic slaughter slab operations, improved transportation system for both livestock and meat is therefore recommended; not only for Akinyele, but all abattoirs and slaughter slabs in Nigeria.     

PROTON IRRADIATION OF FELINE NASAL PLANUM SQUAMOUS CELL CARCINOMAS USING AN ACCELERATED PROTOCOL

Fifteen cats were treated for squamous cell carcinoma of the nasal planum using proton beam radiation. The protocol used was accelerated with eight equal fractions given on four consecutive days, with a minimum of six hours between fractions. Total dose of radiation delivered was escalated with nine cats receiving 40.4 CGE (60Co Gy equivalent), and three cats each receiving 42.4 and 44.8 CGE. Complete response to the protocol was 60% (9/15), partial response was 33% (5 of 15), and no response was seen in 6.6% (1 of 15). Tumor control rate at one year was 64% and no cat had tumor recurrence after one year. Median survival was 946 days (+/- 516 days). Side effects were minimal with no severe reactions noted in the early or late period. This protocol offers an effective treatment for squamous cell carcinoma of the feline nasal planum with minimal side effects and may be adaptable to conventional radiation sources particularly when the field size is very small.     

Suspended Solids from Baitfish Pond Effluents in Drainage Ditches

Effluents from aquaculture facilities vary between species and among production systems. Drainage ditches commonly convey effluents from central Arkansas baitfish ponds. Ditches could potentially reduce suspended solids prior to effluent release into receiving streams through settling. We characterized suspended solids in effluents from baitfish ponds and evaluated changes in suspended solids in drainage ditches. We also characterized drainage ditches based on width, depth, slope, and percent vegetation cover. Average (± SD) total suspended solids (TSS) at the point of discharge was 52 (± 41) mg/L, while volatile suspended solids (VSS) averaged 22 (± 23) mg/L. Screening effluents did little to alter their composition. Approximately 76% of TSS were less than 5 μm. There were no significant changes in effluent solids along drainage ditches 100 m from the point of discharge and no significant correlations between ditch characteristics and changes in either TSS or VSS. Existing ditches are quite variable and are not necessarily effective in removing solids present in baitfish effluents. Screening and use of ditches as settling basins seem impractical for effluent treatment given the characteristics of solids in baitfish effluents.     

Time Course Transformations and Fate of Mercury in Aquatic Model Ecosystems

In order to achieve remediation of contaminated substrates, phyto-extraction in pot experiments utilizing lettuce seedlings as universal accumulator plants was investigated. As test substrates, mine tailings from Shiheung and Okdong mines in Korea (particularly high in Pb, Zn, Cu, and Cd), as well as samples from historic mining site at Oberzeiring in Austria (particularly high in Pb, Sb and As) were used, and compared with adjacent farmland soils. After 21 days of growth in the test substrate, the lettuce plants were harvested, and the adjacent soils parted in bulk and root soils. Special soil bacteria, adapted to high Cd levels (Exiguobacter sp.) and capable of adsorbing large amounts of cadmium from solution, as well as perlite (Samson Perlite Inc.) were added to the test substrates before plant growth. Speciation changes in the solids were investigated by sequential leaching, utilizing neutral MgCl₂ (exchangeable), 0.16 M acetic acid, hydroxylamine pH 2, oxalate pH 3, H₂O₂ oxidation, and reflux with aqua regia. Plant growth induced differentiation between root and bulk soils, the differences were more pronounced for the non-contaminated controls. The iron-hydroxide phase increased about 30%, and also the amount of iron-hydroxide bound Be, Cd, Co, Cu, Mg, Mo, Sb and V concentrations, coming mainly from less mobile fractions. The Mn hydroxide phase, however (hydroxylamine), remained rather constant. After plant growth, the root soils were significantly lower in available P, and significantly higher in available Ca, Mn, and Na than the corresponding bulk soils. Addition of Cd-adapted soil bacteria led to a severe decrease of plant yield, but metal uptake changed in both directions. Exchangeable P in both root and bulk soil decreased, and Be, Co, Cr, Fe, K, Li, Mg, Mn, Ni, and Sr in the residual organic fraction increased. This can be interpreted as competition for nutrients, dissolution of residuals by bacterial action, and adsorption to a tightly bound biomass. Addition of perlite hardly affected the plant yield, and again metal uptake changed in both directions, but led to a decrease of siderophilic elements in the Fe- and Mn hydroxides of the bulk soil. In the root soil, perlite addition above all decreased available K, P and As, with respect to the untreated samples. Bacteria addition to perlite treated soils shifted some elements from weak acid mobile towards less available fractions.