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Objective Describe the pharmacokinetics and pharmacodynamics of intravenous hydromorphone in healthy horses. Study design Masked, randomized, cross-over, Latin square design. Animals A group of eight healthy adult horses Methods Horses were administered each of four treatments with an 8 day washout. Treatments groups included intravenous hydromorphone 0.02 mg kg–1 (LD), 0.04 mg kg–1 (MD), 0.08 mg kg–1 (HD) and saline (P). Blood samples for hydromorphone analysis were obtained for 24 hours after treatment. Plasma hydromorphone was quantified and pharmacokinetic parameters were determined using non-compartmental analysis. Pharmacodynamic data collected for 24 hours after treatment included thermal nociceptive threshold, heart rate (HR), respiratory rate (fR) and rectal temperature, and analyzed using mixed-effects linear models. Results Mean (± standard deviation) hydromorphone terminal half-life (t1/2), systemic clearance and apparent volume of distribution at steady state (Vdss) were 18.1 ± 18.6, 34.0 ± 12.8, and 41.3 ± 32.5 minutes, 66.6 ± 5.3, 550.0 ± 76.4, and 92.7 ± 13.9 mL kg–1 minute–1, and 1118 ± 369, 1460 ± 325 and 2242 ± 950 mL kg–1 for treatments LD, MD and HD, respectively. Thermal threshold increased significantly compared to baseline for all treatments for up to 12 hours. HR was elevated above baseline in treatments LD, MD and HD, extending to 30, 15 and 105 minutes after treatment, respectively. Respiratory rate was elevated above baseline in treatments MD and HD from 30 to 195 minutes and from 45 to 480 minutes after treatment, respectively. Temperature was elevated above baseline in treatment HD until 255 minutes after treatment. Conclusions Hydromorphone exhibited a short t1/2, rapid clearance and large Vdss in horses. It also provided a dose-dependent increase in thermal threshold with associated increases in HR, fR and rectal temperature. Clinical relevance Hydromorphone 0.04 mg kg–1 provided clinically relevant thermal antinociception with minimal adverse effects.

The ecological outcomes of civic environmental stewardship are poorly understood, especially at scales larger than individual sites. In this study we characterized civic environmental stewardship programs in the Green-Duwamish watershed in King County, WA, and evaluated the extent to which stewardship outcomes were monitored. We developed a four-step process based on the Open Standards for the Practice of Conservation to structure our evaluation and to make recommendations for future monitoring of ecological outcomes of stewardship activities. Environmental stewardship, primarily in the form of restoration projects, was common throughout the lower and middle watershed. The distribution of stewardship sites was influenced by population density, political and program boundaries, and financial and technical resources. Conceptual frameworks that link conservation goals, ecological threats, management strategies, and monitoring were rare and incomplete. Collaboration among programs was an important component of stewardship in the watershed, although communication gaps were identified between geographic regions and different ecosystems. Monitoring efforts were relatively common but unevenly distributed, often unsystematic, and usually dictated by project maintenance, funding purpose, or a program’s standard practices, rather than specific ecological outcomes and goals. As a result, monitoring results were rarely and inconsistently used for management. We recommend improving stewardship monitoring by clearly linking stewardship activities to specific conservation goals and objectives, developing reasonable quantitative outcome metrics that link upland and aquatic environments, and improving coordination and learning of monitoring efforts among multiple stewardship programs and actors.

Urban forest management plans serve as a municipality's guiding document for management of its urban trees and urban forest. This paper presents results of a content analysis and evaluation of the comprehensiveness of 39 urban forest management plans in Washington State. Comprehensiveness is the degree to which a plan includes a review of the current state of the resource, a vision for the future state, goals and objectives, an action plan for implementation, and a plan for monitoring progress. We also explored whether municipality size, community involvement, plan author, or funding source influence plan comprehensiveness. Plan comprehensiveness varies, and although most plans included the results of a tree inventory, very few conducted a full assessment of the current state of the urban forest. Tree maintenance, tree establishment, and tree protection were addressed most frequently, and many of the plans included a vision statement. The majority of plans included detailed action steps for implementing goals related to tree maintenance and tree establishment, and about a quarter of the plans included an implementation plan. Very few plans addressed monitoring and adaptive management, and no plan included a detailed strategy for monitoring the implementation of the plan. Larger municipalities tend to have more comprehensive plans, and community involvement in the plan development process appears to positively influence the overall comprehensiveness score. No relationship was found between plan author or receipt of grant funding and plan comprehensiveness. Our approach for evaluating plan comprehensiveness suggests a useful framework for future plan development, revision, and evaluation.

Peripheral blood mononuclear cells (PBMCs) were obtained from 6 foals1 week of age, 6 foals between 3 and 4 months of age, and 10 adult horses. PBMCs were stimulated with concanavalin A (ConA) or calcium ionomycin-phorbol myristate acetate (CaI-PMA) and the frequency of interferon IFN-gamma and IL-4 secreting cells was measured using an equine-specific ELISPOT assay. The number of IFN-gamma secreting cells was significantly lower in both groups of foals than in adult horses regardless of the mitogen used for stimulation. The number of IFN-gamma secreting cells was significantly higher in cells stimulated with CaI-PMA than in cells stimulated with ConA. In cells stimulated with CaI-PMA, the number of IL-4 secreting cells was significantly lower in both groups of foals compared to adult horses. In adult horses only, CaI-PMA stimulation resulted in significantly more IL-4 secreting cells than ConA stimulation. Regardless of age, the ratio of IFN-gamma/IL-4 spot forming cells (SFC) was significantly higher in cells stimulated with CaI-PMA than in cells stimulated with ConA. These findings indicate that the frequency of IFN-gamma and IL-4 secreting cells is lower in foals than in adult horses and that the type of mitogen used has a profound effect on the relative production of both cytokines.