Basin‐scale distribution and haplotype partitioning in different genetic lineages of the Neotropical migratory fish Salminus brasiliensis

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Antifungal activity of <Emphasis Type="Italic">Boerhavia diffusa</Emphasis> L. extract against <Emphasis Type="Italic">Phytophthora</Emphasis> spp. in tomato and pepper

A new longidorid nematode, Longidorus persicus n. sp., is described and illustrated from a population extracted from soil associated with wild rose (Rosa sp.) naturally growing in the mountains close to the village of Cheshmeh-e-Nezamei near the city of Gilan-e-Gharb, Kermanshah province, western Iran. The new needle nematode is characterised by a large body size (6550–7763 μm), an anteriorly flattened lip region, ca 13 μm wide, distinctly set off from body contour by a depression, amphidial fovea large, pocket shaped, slightly asymmetrically bilobed, a moderately long and flexible odontostyle ca 86 μm long, stylet guiding ring located at ca 25 μm from anterior end, posterior arrangement of the pharyngeal gland nuclei, vulva almost equatorial (49–54 %), tail short, about 3/4 of its width, dorsally convex-conoid, with rounded terminus, with a c’ ratio ca 1.3, bearing three pairs of caudal pores and male rare (ratio 1:10 females) with spicules ca 46 μm long. Integrative diagnosis was completed with molecular data obtained using D2-D3 expansion segments of 28S rDNA, ITS1-rDNA, and partial 18S-rDNA. The phylogenetic relationships of this species with other Longidorus spp. using D2-D3 expansion segments and partial 18S-rDNA indicated that L. persicus n. sp. clustered together with L. perangustus and L. euonymus: both of them sharing an anteriorly flattened lip region and distinctly set off from body contour by a depression.     

Effects of post-fire management practices and slope-aspect on medium-term Spanish black pine regeneration: implications of using a direct seeding strategy in burnt areas

The natural regeneration of non-serotinous Spanish black pine (Pinus nigra Arn. ssp. salzmannii) is known to be null or limited after severe wildfires. However, it remains challenging to define efficient management strategies within the burnt area, which can help to increase the post-fire resilience of this species. We conducted a direct seeding experiment during 2011–2015 to assess the effect of different post-fire management treatments (control, soil ripping, woodchips, and soil ripping?+?woodchips) performed in opposite slope-aspects (north- and south-facing) on pine emergence, seed predation, survival, growth, and biomass allocation during the early stages of seedling development (1–5 years) after a severe wildfire. Our results showed that the slope-aspect did not have an important effect in both the seedling emergence and seed predation rates. In contrast, the influence of slope-aspect was significant as both survival and growth of pine seedlings were reduced at the south-facing slope-aspect compared to the north-facing slope-aspect due to harsher environmental conditions. A variable and reduced impact on seedling emergence and seed predation rates was induced by both soil ripping and woodchips treatments. Overall, post-fire management treatments helped to enhance survival rates during early growth stages, although this effect was short-lasting. This knowledge can be used to define post-fire seeding management strategies oriented to enhance the resilience of severely burnt pine forest stands; therefore, while both the soil ripping and woodchips treatments might not be practices leading to increase their post-fire regeneration, direct seeding at north-facing slope-aspects could be a more appropriate management strategy.     

Interaction with soil enhances the toxic effect of iodide and iodate on barley (Hordeum vulgare L.) compared to artificial culture media during initial growth stage

Iodine is an essential trace element for humans, and while plants play an important role in its supplementation, they can also be subject to iodine toxicity. Herein, comparison of iodide and iodate effects on barley (Hordeum vulgare L.) development was evaluated in laboratory experiments when it was cultivated in iodine-spiked agar cultivation media and agricultural soil. Our results show that iodine toxicity is highly dependent on its chemical form and also reflects growth substrate type. Barley responses to iodine presence in agar and soil media suggest that iodide has more severe inhibitory effects than iodate on plant growth. Furthermore, the detrimental effect of iodine notably increased in soil with biomass synthesis as the most sensitive physiological parameter to adverse iodide and iodate effects. However, mild iodate and iodide stimulation of barley growth was observed which implies they are beneficial for growth at low concentrations. These effects were more intense when iodine was applied as iodide, especially in soil cultivation system where natural geochemical processes lead to alteration in iodine speciation which significantly increases plant sensitivity to iodine toxicity.     

Tree cavity densities and characteristics in managed and unmanaged Swedish boreal forest

In forests worldwide, ～10?40% of bird and mammal species require cavities for nesting or roosting. Although knowledge of tree cavity availability and dynamics has increased during past decades, there is a striking lack of studies from boreal Europe. We studied the density and characteristics of cavities and cavity-bearing trees in three categories of forest in a north-Swedish landscape: clearcuts with tree retention, managed old (>100 years) forest, and unmanaged old forest. Unmanaged old forests had significantly higher mean density of cavities (2.4?±?2.2(SD)?ha^?1) than managed old forest (1.1?±?2.1?ha^?1). On clearcuts the mean cavity density was 0.4?±?2.3?ha^?1. Eurasian aspen (Populus tremula) had a higher probability of containing excavated cavities than other tree species. There was a greater variety of entrance hole shapes and a higher proportion of cavities with larger entrances in old forest than on clearcuts. Although studies of breeding success will be necessary to more accurately assess the impact of forest management on cavity-nesting birds, our results show reduced cavity densities in managed forest. To ensure future provision of cavities, managers should retain existing cavity-bearing trees as well as trees suitable for cavity formation, particularly aspen and dead trees.     

Characterization of the urogenital microbiome in Miniature Schnauzers with and without calcium oxalate urolithiasis

BackgroundCalcium oxalate (CaOx) uroliths are common in dogs. Humans with CaOx urolithiasis exhibit alterations of the urinary and urogenital microbiomes that might mediate urolith formation. Detection of urogenital microbes associated with CaOx in dogs could inform disease pathophysiology.ObjectiveTo identify compositional differences in the urogenital microbiome of Miniature Schnauzers with and without CaOx uroliths.AnimalsNineteen midstream, voided urine samples from Miniature Schnauzers with (n = 9) and without (n = 10) a history of CaOx urolithiasis.MethodsAnalytical cross‐sectional study. Microbial DNA was extracted from previously frozen urine samples and sequenced for the bacterial 16S rRNA V3‐V4 hypervariable regions. Diversity and composition of microbial populations were compared between urolith formers and controls.ResultsAlpha and beta diversity measures were similar between groups. Five individual bacterial taxa differed in abundance (indicator values >0.5 and P < .05): Acinetobacter, 2 Geobacillus variants, and Hydrogenophaga were overrepresented in the urine of urolith formers, and Sphingopyxis was overrepresented in controls. Two distinct subtypes of urine microbial composition were observed based on beta diversity measures, independent of urolith status, and other clinical variables.Conclusions and Clinical ImportanceAlthough we did not detect a difference in the overall urogenital microbial composition between groups, observed differences in individual bacterial taxa might be clinically relevant. For example, Acinetobacter was overrepresented in urolith formers and is associated with CaOx urolithiasis in humans. Two unique clusters of the microbiome were identified, independent of urolith status, which may represent distinct urotypes present in Miniature Schnauzers.     

Exudative epidermitis and porcine circovirus-2 infection in a Swedish SPF-herd

An outbreak of exudative epidermitis (EE) among piglets in a Swedish SPF-herd initiated a survey for indications as to the cause of disease.The herd was established by caesarean section and has been closed to all new animal material, with the exception of semen for artificial insemination (AI). The study comprised serum samples from the SPF-herd over a 10-year period (n=109) and a close monitoring of animals in the herd during the period after the EE outbreak. Serum samples from conventional boars at the AI-station servicing the herd were also included (n=9). All serum samples were tested for antibodies to porcine circovirus-2 (PCV-2). In addition, 3-week-old piglets from three litters (n=24) farrowed close after the initial EE outbreak were closely monitored for clinical signs of skin disease, sampled for Staphylococcus hyicus, tested for antibodies to porcine parvovirus and in sequentially collected serum samples tested for interferon-alpha (IFN-alpha) and interleukin-6.The PVC-2 serology showed that animals in the herd were sero-negative at least until 2 months prior to the EE outbreak. During the period close after the EE outbreak the animals showed varying levels of antibodies to PCV-2 but all the tested animals had sero-converted 4 months later. The AI boars were also sero-positive to PCV-2 at the time of the EE outbreak. Animals in the SPF-herd remained sero-positive to PCV-2 during the following 7 years. In the monitored litters, one piglet had clinical EE and 15 piglets displayed defined erythemas on the abdomen. Fourteen of the piglets also had IFN-alpha in serum on one or more occasions during the study, indicating viral activity among the animals. S. hyicus was isolated from all of the piglets from the earliest sampling point (3 days of age) and onwards, irrespective of clinical signs. PCV-2 was isolated from lymph node tissue collected from one of the EE affected pigs.Further, increases in the number of stillborn piglets, small litters (<6 piglets) and repeat breeders could be correlated to the time of PCV-2 sero-conversion. Coincidence of active viral infection and sero-conversion to PCV-2 points to the virus as the cause of the EE outbreak and reproductive disturbances.