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Background Objectives Animals Materials and Methods Results Conclusions and Clinical Relevance Epicutaneously house dust mite‐sensitised (HDM‐S) healthy dogs are commonly used as canine atopic dermatitis (cAD) models; however, the exact mechanisms of HDM‐induced AD immune activation in HDM‐S and HDM‐nonsensitised (NS) dogs remain unclear.To characterise the inflammatory and pruritogenic transcriptome of acute epicutaneous HDM‐induced skin lesions at 6 h and 24 h in HDM‐NS and HDM‐S dogs; untreated skin at 0 h from each dog served as control.Six HDM‐S and six HDM‐NS laboratory beagles.Processed expression data from GEO deposited by Schamber et al. (G3 (Bethesda), 2014, 4 and 1787) (GSE58442) were downloaded and analysed using R and the Bioconductor package. Significance analysis was performed with the limma package; genes with false discovery rate <0.05 and fold‐change ≤/≥1.5 were considered significantly differentially expressed (DEGs).A 2D principal component analysis revealed no clear separation between HDM‐NS and HDM‐S dogs at 6 h and 24 h time points. HDM‐induced skin lesions in sensitised and nonsensitised dogs at the 24 h time point showed significant upregulation of T helper cell (Th)2 genes (interleukin [IL]‐4R, IL‐5, IL‐13, CCL13 and CCL17), as well as proinflammatory‐ (LTB, IL‐1A and IL‐18), Th1‐ (CXCL10, OASL and MX‐1) and Th17‐related markers (IL‐17B, IL‐17F, CCL19 and CCL20). The key Th22‐related maker, IL‐22, was upregulated only in the HDM‐S group at the 24 h time point. Both groups at 24 h featured significant upregulation of several noncytokine pruritogens, such as trypsin, chymase, cathepsin S, periostin and neuromedin B.Taken together, we establish that epicutaneous HDM patch application induces immune changes in HDM‐NS dogs with Th2 dominance and activates several itch‐promoting pathways. [ABSTRACT FROM AUTHOR]

Cover crops are multifunctional tools that mitigate environmental impacts of agriculture, enhance resilience to weather extremes and suppress weeds and arthropod pests. Cover crops provide non‐crop food and habitat resources that attract natural enemies of pests, but their outcomes for pest management are less clear in regions where keystone mutualisms between red imported fire ants and aphids dominate. Here, we manipulate ant exclusion treatments and cover crop treatments (living mulches and terminated cover crops) that vary in food/habitat resources and examine responses of ants, aphids, other herbivores and predators in a cotton agroecosystem. Living mulches reduced both ants and aphids in the crop canopy by 97% and 93%, respectively, relative to bare soil treatments, and terminated cover crops reduced them as well by a lesser degree (~50%). Non‐aphid herbivores occurred in low densities system‐wide and increased in living mulches, whilst native predators had variable responses to cover crops and ant exclusion. Cover crops had no effect on prey removal in the crop canopy, but living mulches tripled rates of weed seed biocontrol, relative to bare soils. Cover crops elicited a shift in fire ant foraging from cotton foliage downward to the soil‐surface, preventing competitive exclusion by keystone ant/aphid mutualists that dominate crop monocultures. Cover crops altered the system‐wide impacts of fire ants: reducing ecosystem disservices (i.e. aphid tending) and enhancing ecosystem services (i.e. weed seed biocontrol). These results provide incentives for cover crop adoption as a regenerative practice in large‐scale commercial agriculture. [ABSTRACT FROM AUTHOR]

Herbivorous insects generally choose host plants that optimize their growth. However, many specialists choose chemically defended host plants that slow their growth, prioritizing protection from natural enemies.Invasive specialist herbivores may have an added advantage in their non‐native range where they lack co‐evolved specialist natural enemies, in addition to being unpalatable to generalist predators.Here, we explore the diet preferences of the invasive yellowmargined leaf beetle, Microtheca ochroloma and those of native natural enemies. We measured M. ochroloma preferences among six Brassica cultivars varying in glucosinolate concentrations.In both field and laboratory experiments, M. ochroloma preferred the relatively less defended host plants, mizuna and Chinese cabbage. M. ochroloma grew quickest on mizuna.Generalist predators also preferred to eat M. ochroloma larvae that had been fed mizuna in choice trials, yet in the field, predatory insects were least commonly found on mizuna, and most commonly found on plants dominated by native herbivores.M. ochroloma consumes plants that increase their susceptibility to predators, but predation pressure in the field appears to be generally low. Our results suggest that invasive specialist herbivores may prioritize growth over protection against natural enemies.Weak top‐down regulation of specialist herbivore invaders might enable them to exploit less‐defended host plants in their novel range that facilitate faster growth and exacerbate crop damage. Invasive pests may be more effectively managed by leveraging plant preferences in the novel host range in trap crop systems. [ABSTRACT FROM AUTHOR]

Plant diversity aboveground can exert top‐down pressure on herbivores by attracting predatory insects, while organic soil amendments rich in beneficial microbes can limit herbivores from the bottom‐up by enhancing plant defensive chemistry. Aboveground and belowground forces always operate simultaneously to shape herbivore pressure, but understanding how they interact is a longstanding and persistent challenge.Here, we examine how organic composts mediate the effects of plant diversity across trophic levels, using zucchini plants (Cucurbita pepo) as a study system. Over two field seasons, we manipulated vermicompost treatments in 18 experiments in school gardens that varied in surrounding plant and floral resource diversity and measured responses of insect herbivores and their natural enemies.Vermicompost strengthened a positive relationship between flower richness and foliar‐feeding omnivores, suggesting that robust reservoirs of omnivores at flower‐rich sites mounted stronger responses to compost‐treated host plants.Predators increased with flower richness, but were not affected by vermicompost.Net outcomes of vermicompost and plant diversity were neutral for herbivores.Synthesis and applications. Altogether, our results reveal that bottom‐up factors protecting plants are modified by their environmental context, and may more effectively attract natural enemies in landscapes with diverse floral resources. Therefore, we recommend augmentation of biodiversity aboveground (i.e. floral resources) together with biodiversity belowground (organic soil amendments) to strengthen crop protection. [ABSTRACT FROM AUTHOR]

Copyright of Veterinary Dermatology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Increasing plant diversity in agroecosystems is well‐known to strengthen natural pest suppression, yet reliably predicting which non‐crop management practices best support natural enemies remains a challenge. Farmers often supplement diversity with managed flower patches or by allowing weedy non‐crop plant growth, both of which may support diverse, abundant and balanced communities of insect predators that provide biocontrol.At the same time, evenness among predators and effectiveness of biocontrol may be compromised by dominant arthropod invaders that co‐benefit from non‐crop diversity.We examined whether floral resources or adjacent weeds had stronger effects on the evenness and abundance of natural enemies by surveying plants and insects on zucchini crops at 37 organic farms.Neither flower richness nor weed richness affected insect predator evenness. Instead, the abundance of an invasive predator, the red imported fire ant (Solenopsis invicta Buren), increased with floral resource diversity, which negatively predicted the evenness and abundance of non‐invasive predators.These results suggest that floral diversity might be a less reliable predictor of natural enemy diversity when invasive predators interfere. Habitat management recommendations for bolstering biocontrol services should consider and potentially mitigate unintended consequences of floral resource provisions on farms where invasive predators dominate. [ABSTRACT FROM AUTHOR]

Diet composition modulates animals' ability to resist parasites and recover from stress. Broader diet breadths enable omnivores to mount dynamic responses to parasite attack, but little is known about how plant/prey mixing might influence responses to infection.Using omnivorous deer mice (Peromyscus maniculatus) as a model, we examine how varying plant and prey concentrations in blended diets influence resistance and body condition following infestation by Rocky Mountain wood ticks (Dermacentor andersoni).In two repeated experiments, deer mice fed for 4 weeks on controlled diets that varied in proportions of seeds and insects were then challenged with 50 tick larvae in two sequential infestations.The numbers of ticks successfully feeding on mice declined by 25% and 66% after the first infestation (in the first and second experiments, respectively), reflecting a pattern of acquired resistance, and resistance was strongest when plant/prey ratios were more equally balanced in mouse diets, relative to seed‐dominated diets.Diet also dramatically impacted the capacity of mice to cope with tick infestations. Mice fed insect‐rich diets lost 15% of their body weight when parasitized by ticks, while mice fed seed‐rich diets lost no weight at all.While mounting/maintaining an immune response may be energetically demanding, mice may compensate for parasitism with fat and carbohydrate‐rich diets.Altogether, these results suggest that a diverse nutritional landscape may be key in enabling omnivores' resistance and resilience to infection and immune stressors in their environments. [ABSTRACT FROM AUTHOR]

Impassable dams on major tributaries to the Willamette River, Oregon, have restricted access to historical spawning habitat for returning adult Chinook Salmon Oncorhynchus tshawytscha. To restore these populations, some fish are collected and transported in trucks upstream of dams (i.e., adult trap‐and‐haul operations). However, persistently high prespawn mortality (PSM) rates in these programs have hindered conservation efforts. The objective of this study was to evaluate environmental factors and individual fish traits associated with PSM in Chinook Salmon populations that were transported and released upstream of dams in three Willamette River tributaries. Annual PSM of tagged and untagged female salmon ranged from 6% to 88% across 7 years. Mortality was higher in warmer years and in warmer tributaries, consistent with rangewide studies of PSM in Chinook Salmon. Effects of individual traits were mixed across sites: longer salmon and those released relatively early or late in the migrations had higher mortality. We conclude that strategies designed to minimize adult Chinook Salmon exposure to warm water temperatures, as well as additional research into both proximate and ultimate causes of PSM, may lead to better management and conservation outcomes for outplanted populations, including those in Willamette River tributaries. [ABSTRACT FROM AUTHOR]

Nutrients regulate herbivore growth from the 'bottom‐up' via improved plant vigour and food quality. Nitrogen also affects 'top‐down' control of herbivores by moderating attraction of predators and the rates at which they consume herbivorous prey.Tri‐trophic consequences of nitrogen availability are more challenging to predict among omnivorous natural enemies who feed on both plants and herbivores, limiting our ability to predict net outcomes of nutrient availability in food webs.In a two‐year field survey of insects on zucchini host plants at 48 sites, I predicted that both herbivores and foliar‐feeding omnivores would increase with nutrient availability, while predators would not.My results revealed positive relationships between omnivores and foliar nitrogen concentrations, while predators had neutral responses to foliar N. Surprisingly, herbivores declined with increasing foliar N across the field sites.Greenhouse experiments re‐enforced these patterns, as herbivore growth inversely correlated with soil N concentrations in communities that included foliar‐feeding omnivores. Conversely, herbivore growth was uncorrelated with soil N on plants with predators, nor on predator‐free plants.These results suggest that omnivores mount strong and consistent responses to nitrogen in plant tissues in a variety of ecological contexts. In environments where omnivorous arthropods can thrive, their recruitment to nitrogen‐rich plants may increase predation and thereby counterbalance and stabilize 'bottom‐up' increases in herbivore performance supported by enhanced foliar nutrition. [ABSTRACT FROM AUTHOR]

B Background - b Chloroquine (CQ) is a prototypical systemic and intradermal pruritogen for histamine-independent (nonhistaminergic) itch in mice and humans. By contrast to the systemic CQ-induced pruritus reported previously in healthy mice and dogs, no significant pruritic behaviours were observed after CQ injection, regardless of the route of administration. Pruritus (itch), defined as a sensation that provokes a desire to scratch, is the most common clinical sign of many dermatological diseases in dogs.[1] Basic research has advanced our understanding of the mechanisms underlying pruritus. (b) Intradermal CQ injections induced mild acute pruritic behaviours at the site of injection of 200 µg and 400 µg CQ in dogs; however, these differences were not statistically significant for the pruritic seconds or episodes for either CQ concentration. gl. [Extracted from the article]

Back Bay is an oligohaline, coastal bay in southeast Virginia, USA. Since 2004, leeches have been observed in the oral cavities of largemouth bass (Micropterus salmoides) in this body of water. Leeches (Myzobdella lugubris) have previously been documented in the oral cavities of largemouth bass in the Currituck Sound, which is confluent with Back Bay on its southern border. Supplemental stocking of largemouth bass in Back Bay since 2009 has resulted in an increasing population; however, concern exists that leech infestation may be negatively affecting health of larger fish, which are still less abundant than expected. Despite the wide distribution of this leech, there is little available literature regarding its health impacts on hosts. In this study, we examine potential impacts of oral leech infestations on stress markers and haematological parameters of largemouth bass in Back Bay. No significant changes in plasma glucose or cortisol were observed between leech‐infested and uninfested fish, and haematological parameters were not significantly different between the groups. Further, there was no evidence of systemic infections associated with leech infestation. [ABSTRACT FROM AUTHOR]

Coho Salmon Oncorhynchus kisutch were historically absent from a major Columbia River subbasin, the upper Willamette River (UWR), until a fishway was installed at Willamette Falls and a sustained stocking program was implemented in the 1950s. Despite decades of stocking from three diverse source populations (early run, late run, and coastal Coho Salmon) during the second half of the twentieth century, adult abundance above the falls was less than 1,000 annually during the 1990s. A recent surge (>25,000 adults in 2009) has raised concerns about potential interactions with two native anadromous salmonids listed under the U.S. Endangered Species Act: UWR winter‐run steelhead O. mykiss and UWR spring‐run Chinook Salmon O. tshawytscha. We analyzed Coho Salmon stocking records and estimates of abundance from 1954–2017 to summarize population history, demographics, and adult phenology. We also characterized current Coho Salmon distribution using radiotelemetry (n = 219 adults in 2014) and evaluated potential mechanisms associated with changes in adult abundance. We identified a shift in adult migration timing over the time series that was consistent with an increase in late‐run traits and environmental changes affecting migration cues. The distribution of radio‐tagged adults among UWR subbasins was only weakly correlated with past stocking efforts, suggesting that habitat conditions, stocked phenotype, adaptation and range expansion by descendants of the relict stocked populations, or colonization from regional source populations strongly influenced current subpopulation abundance. Annual counts of returning UWR Coho Salmon were positively correlated with counts of Columbia River Coho salmon, suggesting a shared response to freshwater habitat or ocean conditions. Regardless of the underlying mechanisms affecting UWR Coho Salmon distribution and population size, the results illustrate the complex dynamics between changing landscapes and migration corridors, the introduction of nonnative species for harvest management goals, and the potential for nonnative fish to affect the conservation of native populations. [ABSTRACT FROM AUTHOR]

Background - Topical Janus kinase (JAK) inhibition is a promising therapeutic target forseveral inflammatory skin diseases of humans. Objectives - To evaluate the anti-inflammatory effect of tofacitinib, a JAK 1/3 inhibitor, on immediate and latephase skin reactions in dogs. Animals - Five healthy laboratory beagle dogs. Methods - Topical tofacitinib (total daily dosage: 0.5 mg/cm2) or its gel vehicle were applied on either the left or right lateral thorax of each dog for eight days. Three days before application and after eight days of topical treatment, intradermal injections of histamine and anticanine-IgE antibodies were performed on both sides; they were evaluated by an investigator blinded to the interventions. Results - The tofacitinib gel was well-tolerated; one dog developed mild erythema at Day 5 that resolved by the next application. Treatment with tofacitinib reduced histamine and anticanine-IgE global wheal scores (one-way ANOVA, P < 0.005 for both) compared to baseline; there was no significant difference for the vehicle placebo (histamine; P = 0.163; IgE, P = 0.223). Late-phase reactions (LPRs) were markedly, but not significantly reduced after tofacitinib treatment (P = 0.071).A blinded histological evaluation of 6 h-anti-IgE-associated LPRs revealed a significant reduction in the total leucocyte superficial dermal cellularity (P = 0.022), as well as eosinophil (P = 0.022) and mast cell (P = 0.022) counts at tofacitinib-treated sides compared with pretreatment values. Post-treatment complete blood counts and serum chemistry profiles did not show relevant tofacitinib-induced changes. Conclusions - Our observations suggest that topical tofacitinib exerts an inhibitory effect on activated canine skin-emigrating immune cells; this drug should be investigated further as a topical immunosuppressive drug in dogs. [ABSTRACT FROM AUTHOR]

Abstract: Plant defenses often mediate whether competing chewing and sucking herbivores indirectly benefit or harm one another. Dual‐guild herbivory also can muddle plant signals used by specialist natural enemies to locate prey, further complicating the net impact of herbivore–herbivore interactions in naturally diverse settings. While dual‐guild herbivore communities are common in nature, consequences for top‐down processes are unclear, as chemically mediated tri‐trophic interactions are rarely evaluated in field environments. Combining observational and experimental approaches in the open field, we test a prediction that chewing herbivores interfere with top‐down suppression of phloem feeders on Brassica oleracea across broad landscapes. In a two‐year survey of 52 working farm sites, we found that parasitoid and aphid densities on broccoli plants positively correlated at farms where aphids and caterpillars rarely co‐occurred, but this relationship disappeared at farms where caterpillars commonly co‐occurred. In a follow‐up experiment, we compared single and dual‐guild herbivore communities at four local farm sites and found that caterpillars (P. rapae) caused a 30% reduction in aphid parasitism (primarily by Diaeretiella rapae), and increased aphid colony (Brevicoryne brassicae) growth at some sites. Notably, in the absence of predators, caterpillars indirectly suppressed, rather than enhanced, aphid growth. Amid considerable ecological noise, our study reveals a pattern of apparent commensalism: herbivore–herbivore facilitation via relaxed top‐down suppression. This work suggests that enemy‐mediated apparent commensalism may override constraints to growth induced by competing herbivores in field environments, and emphasizes the value of placing chemically mediated interactions within their broader environmental and community contexts. [ABSTRACT FROM AUTHOR]

Abstract: We conducted a field experiment to test the hypothesis that intragastric radio‐tagging contributed to increased prespawn mortality (PSM) of adult Chinook Salmon Oncorhynchus tshawytscha after collection and transport to spawning sites above high‐head hydroelectric dams. We assessed PSM rates of 970 wild and hatchery Chinook Salmon collected during trap‐and‐haul operations that were released untagged, tagged with passive integrated transponder (PIT) tags only, or double tagged with PIT tags and radio transmitters, and then recovered as carcasses in two Willamette River, Oregon, tributaries from 2009 to 2015. Results revealed no evidence that PSM rates were higher in PIT‐tagged samples than in untagged (but not unhandled) control samples. The PSM rates in double‐tagged samples were variable among years and between locations and indicated that radio‐tagging effects were absent or small in effect size, on average, within each population. While we did not detect a consistent negative double‐tagging effect across locations and years, results suggest that the potential for radio‐tagging effects should be incorporated in study planning and design. We recommend that researchers use experimental designs that include control groups for directly evaluating tagging and handling effects on study outcomes. [ABSTRACT FROM AUTHOR]

Episodically high adult mortality during migration and near spawning sites has hindered the recovery of threatened spring-run Chinook SalmonOncorhynchus tshawytschain Oregon’s Willamette River basin. In 2011–2014, we assessed migration mortality for 762 radio-tagged adults along a ~260-km reach of the main stem of the Willamette River. Annual survival of salmon to spawning tributaries ranged from 0.791 (95% CI = 0.741–0.833) to 0.896 (0.856–0.926), confirming concerns about mortality in the migration corridor. In a series of general linear models, descaling, marine mammal injuries, and head injuries to adult Chinook Salmon were linked to reduced survival during migration to tributaries. Many injuries were minor (i.e., epidermal abrasions), which we hypothesize were unlikely to have caused direct mortality but may have increased salmon vulnerability to pathogens or other disease processes. Mortality in the main stem was not significantly associated with salmon body size, energetic status, sex, origin (hatchery, wild), river discharge, or water temperature metrics. The ~10–21% estimates of en route mortality in this study provide an important benchmark for the main stem of the Willamette River. The estimates complement ongoing efforts to quantify mortality of adult Chinook Salmon in Willamette River tributaries and after collection and transport to spawning sites above high-head hydroelectric dams. Received September 15, 2016; accepted December 1, 2016 Published online March 3, 2017 [ABSTRACT FROM AUTHOR]

A replica-mask method is presented to measure the contrast of character strokes on emissive displays under carefully controlled illumination. The method accounts for veiling glare introduced into the detector by the bright areas surrounding the dark characters. A sampling sphere is used to provide a uniform diffuse surround. Measurements of the diffuse reflectances are provided with specular included and with specular excluded. For emissive displays, the contrast depends both upon the darkroom characteristics of the emissive display and its reflective characteristics. Details are provided to replicate the measurement procedure. [ABSTRACT FROM AUTHOR]

The article presents a study which explained the replica-mask method to measure the contrast of character strokes on reflective displays. The researchers developed a sampling sphere to observe the uniform hemispherical reflectances, with and without specular, of dark characters with bright background for three reflective displays and engaged a replica mask to determine the veiling-glare contribution in the camera. Results showed the same contrast as the ratio of reflectances.

Previous studies of employee ownership have conceptualized its chief attitudinal outcome principally as an emotional bond to the organization (i.e. affective commitment), despite a growing consensus that commitment is multifaceted. Using a sample of airline pilots, we assessed relationships between ESOP (employee stock ownership plan) attributes and three-component commitment (Meyer & Allen, 1991). Regarding continuance commitment, high . nancial value was associated with pilots feeling freer to leave rather than being bound to the organization, as side-bet theory suggests. As predicted, perceived workplace empowerment was strongly related to normative commitment--consistent with Meyer and Allen's theoretical formulation emphasizing unful.lled reciprocity norms but inconsistent with the non-contingent, loyalty norm explanation. [ABSTRACT FROM AUTHOR]

Copyright of Veterinary Dermatology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Veterinary Dermatology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Veterinary Dermatology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)