Genetic diversity of international bovine viral diarrhoea virus (BVDV) isolates: identification of a new BVDV-1 genetic group

In the last decade, several studies were performed to characterise bovine viral diarrhoea virus (BVDV) isolates and define genetic groups by genotyping. Much data is now available from GenBank, predominantly sequences from the 5' untranslated region (5'-UTR). In order to find out whether genetic grouping of isolates from different countries could be harmonised, 22 new isolates from five countries were analysed in combination with published sequences. Eighteen of these isolates were typed as BVDV genotype 1 (BVDV-1), and one isolate from Argentina and three isolates from Brazil were typed as BVDV-2. BVDV-1 isolates were clustered into five previously defined genetic groups: BVDV-1a, b, d, e and f. Two isolates from Finland and one from Egypt formed a group which was tentatively labelled as BVDV-1j, since statistical support was low. By using a fragment of the Npro gene for typing, we found that these isolates fall into the same group as a deer strain, and are statistically significant. Some Swiss BVDV strains taken from GenBank were found in a new genetic group which was designated as BVDV-1k. The BVDV-2 isolates included in this study seemed to fall into two genetic groups.     

Seroprevalence for norovirus genogroups GII and GIV in captive non‐human primates

Noroviruses (NoVs) are a major cause of epidemic gastroenteritis in children and adults. Several pieces of evidence suggest that viruses genetically and antigenically closely related to human NoVs might infect animals, raising public health concerns about potential cross‐species transmission. The natural susceptibility of non‐human primates (NPHs) to human NoV infections has already been reported, but a limited amount of data is currently available. In order to start filling this gap, we screened a total of 86 serum samples of seven different species of NPHs housed at the Zoological Garden (Bioparco) of Rome (Italy), collected between 2001 and 2017, using an enzyme‐linked immunosorbent assay (ELISA) based on virus‐like particles (VLPs) of human GII.4 and GIV.1 NoVs. Antibodies specific for both genotypes were detected with an overall prevalence of 32.6%. In detail, IgG antibodies against GII.4 NoVs were found in 18 Japanese macaques (29.0%, 18/62), a mandrill (10.0%, 1/10), a white‐crowned mangabey (16.6%, 1/6) and in an orangutan (33.3%, 1/3). Twelve macaques (19.3%, 12/62), five mandrills (50.0%, 5/10), two chimpanzees (100%, 2/2) and a white‐crowned mangabey (16.6%, 1/6) showed antibodies for GIV.1 NoVs. The findings of this study confirm the natural susceptibility of captive NHPs to GII NoV infections. In addition, IgG antibodies against GIV.1 were detected, suggesting that NHPs are exposed to GIV NoVs or to antigenically related NoV strains.     

Effect of a Lactobacillus animalis strain on composition and metabolism of the intestinal microflora in adult dogs

Probiotics are microorganisms that are added to food to exert beneficial effects on the host. Aim of the present study was the in vitro and in vivo evaluation of the effect of Lactobacillus animalis LA4 (isolated from the faeces of a healthy adult dog) on composition and metabolism of dog intestinal microflora. When added to dog faecal cultures, LA4 reduced enterococci and increased lactobacilli counts throughout the study, whereas C. perfringens counts were significantly reduced at 24 h. After 8 h of incubation, LA4 reduced ammonia and increased lactic acid concentrations. For the in vivo study, nine adult dogs received the freeze-dried preparation of L. animalis LA4 for 10 days. On day 11, faecal lactobacilli were higher than at trial start (6.99 log CFU/g versus 3.35 log CFU/g of faeces) and faecal enterococci showed a trend towards a numerical reduction (P = 0.08). L. animalis LA4 was recovered in all faecal samples collected on day 11 and in four samples at day 15. The present results show that LA4 was able to survive gastrointestinal passage and transitorily colonize the dog intestine where, based on the in vitro results, it could positively influence composition and metabolism of the intestinal microflora. These results suggest that L. animalis LA4 can be considered as a potential probiotic for dogs.     

Effects of no tillage and genetic resistance on sunflower wilt by Verticillium dahliae

From 2001 to 2006 crop seasons three field experiments were run to compare the effect of no tillage (NT) vs. conventional tillage (CT) on Verticillium wilt of sunflower. One experiment had sunflower monocropping (SM) and the others the sequence wheat–sunflower (WS) with 6 years of fescue pasture or seven WS cycles as previous crops. All experimental fields have history of the disease. One cultivar with low resistance was used in SM and two genotype-resistance levels (high and low; characterized by six and eight cultivars each, respectively) in the WS sequences. Leaf mottle severity in all environments, Verticillium dahliae colony forming units (CFU)/g of soil in 2005 or 2006 trials, density of microsclerotia in the stem pith at 0.5 m above the soil line in WS, and grain yield and oil content in WS with fescue as previous crop were recorded. Every year, disease severity was higher in CT than in NT in all trials. In SM, disease severity increased during the 3 years in CT from 58% to 88%, while in NT disease severity remained around the initial level (49%). The V. dahliae-CFU/g of soil after 3 years in SM or three cycles of WS was approximately three times higher in CT than in NT. In WS, density of microsclerotia in stem pith were higher in CT than in NT. In WS with fescue pasture as previous crop, grain yield and oil content tend to increase with NT in relation to CT. The combination of NT and high-resistant genotypes reduced the disease and the production of microsclerotia in stem pith to very low values. NT + high resistance should be viewed as a preventative, not a curative disease management option because the microsclerotia persist in soil for a long time. Therefore, NT + high resistance programs should be initiated early, before inoculum builds up to high levels in the soil. Thus, the combination of NT and high-resistant cultivars promises to be an interesting tool to manage V. dahliae and Verticillium wilt in sunflower and would have potential in other crops like alfalfa, cotton or strawberry.     

Toxicity of arsenic in relation to soil properties: implications to regulatory purposes

Purpose

The present work evaluates the influence of different soil properties and constituents on As solubility in laboratory-contaminated soils, with the aim of assessing the toxicity of this element from the use of bioassays to evaluate the soil leachate toxicity and thereby propose soil guideline values for studies of environmental risk assessment in soil contamination.

Materials and methods

Seven soils with contrasting properties were artificially contaminated in laboratory with increasing concentrations of As. Samples were incubated for 4 weeks, and afterwards, soil solution (1:1) was obtained after shaking for 24 h. The soil leachate toxicity was assessed with two commonly used bioassays (seed germination test with Lactuca sativa and Microtox ® test with Vibrio fischeri).

Results and discussion

The relationship between soluble As and soil properties indicated that iron oxides and organic matter content were the variables most closely related to the reduction of the As solubility, while pH and CaCO₃ increased As solubility in the soil solutions. Toxicity bioassays showed significant differences between soils depending on their properties, with a reduction of the toxicity in the iron-rich soil (no observed effect concentration (NOEC)?=?150 mg kg^?1) and a significant increase in the highly carbonate samples (NOEC between 15 and 25 mg kg^?1).

Conclusions

Soil guideline values for regulatory purposes usually set a single value for large areas (regions or countries) which can produce over- or underestimation of efforts in soil remediation actions. These values should consider different levels according to the main soil properties controlling arsenic mobility and the soil leachate toxicity.     

Bioguided isolation and identification of the nonvolatile antioxidant compounds from fennel (Foeniculum vulgare Mill.) waste

A bioguided isolation of an aqueous extract of fennel waste led to the isolation of 12 major phenolic compounds. Liquid chromatography coupled to atmospheric pressure chemical ionization mass spectrometry (LC/UV/APCI-MS) combined with spectroscopic methods (NMR) was used for compound identification. Radical scavenging activity was tested using three methods: DPPH*, superoxide nitro-blue tetrazolium hypoxanthine/xanthine oxidase, and *OH/luminol chemiluminescence. In addition to products described in the literature, eight antioxidant compounds were isolated and identified for the first time in fennel: 3-caffeoylquinic acid, 4-caffeoylquinic acid, 1,5-O-dicaffeoylquinic acid, rosmarinic acid, eriodictyol-7-O-rutinoside, quercetin-3-O-galactoside, kaempferol-3-O-rutinoside, and kaempferol-3-O-glucoside. The structures of eriodictyol-7-O-rutinoside and quercetin-3-O-glucuronide were completely elucidated by two-dimensional NMR experiments. The isolated compounds exhibited a strong antiradical scavenging activity, which may contribute to the interpretation of the pharmacological effects of fennel.     

Mycorrhizal,nutritional and virgin olive oil parameters affected by groundcovers

Management of olive groves faces the challenge of reconciling yield, soil degradation and virgin olive oil (VOO) quality. We evaluated the effect of replacing tillage management by vegetal groundcovers (GC) on the relationships between mycorrhizal symbiosis, olive nutritional status, and VOO quality under field rainfed conditions. The experiment was set up in 2014 in an existing Cornicabra olive orchard with a Haplic Gypsisol soil under a Mediterranean semiarid climate. Four treatments were replicated four times and consisted of: (1) annual cover of bitter vetch, (2) permanent Brachypodium distachyon, (3) spontaneous vegetation cover (mainly Brassicaceae species), and (4) tilled soil. The use of bitter vetch GC increased the olive root colonization by 50% compared with the tillage treatment. The effect of tillage on VOO differed from that of GC use. Tillage treatment decreased maturity index and its VOO had lower polyphenol content and less luminosity than that from the GC treatments. Olive root colonization, together with changes in nutrients such as Cu, B and other elements resulting from GC use, seems to play an important role in explaining the variability of VOO quality parameters. Although tillage may lead to higher yield by controlling competition for water and nutrients, the introduction of GC in olive groves led to higher polyphenol contents, enhancing VOO quality and, at the same time, protecting soil from erosion.