Evidence-based veterinary dermatology: a systematic review of interventions for treatment of Pseudomonas otitis in dogs

The efficacy and safety of pharmacological interventions to treat canine Pseudomonas otitis externa and media were evaluated based on the systematic review of clinical trials published between 1967 and 2006. Clinical trials were included if Pseudomonas species were cultured from the ears of dogs with otitis externa or otitis media prior to treatment, and if the outcome of these interventions was reported at the end of the study. Studies were compared with regard to design characteristics (randomization generation and concealment, masking, intention-to-treat analyses), benefit (microbiological and/or clinical resolution of the Pseudomonas otitis), and adverse effects. Ten trials reporting data on 162 patients and 13 different pharmacological interventions were identified. Based on the accepted criteria for quality of evidence, there is insufficient evidence for or against recommending the use of any of these treatments for Pseudomonas otitis in dogs. This is largely because there is only one trial supporting the use of each treatment option and none were randomized controlled trials. Future studies need to be prospective, randomized, blinded and controlled; designed to evaluate pharmacological interventions for otitis regardless of the infective organism; have appropriate statistical advice on recruitment numbers, the power of the study and appropriate statistical analysis; include details of underlying conditions and concomitant treatments; and be designed such that inclusion criteria include microbial culture and antimicrobial sensitivity, and outcome assessments include clinical examination, cytology and microbial culture.     

A dynamic, optimal disease control model for foot-and-mouth disease: I. Model description

A dynamic optimization model was developed and used to evaluate alternative foot-and-mouth disease (FMD) control strategies. The model chose daily control strategies of depopulation and vaccination that minimized total regional cost for the entire epidemic duration, given disease dynamics and resource constraints. The disease dynamics and the impacts of control strategies on these dynamics were characterized in a set of difference equations; effects of movement restrictions on the disease dynamics were also considered. The model was applied to a three-county region in the Central Valley of California; the epidemic relationships were parameterized and validated using the information obtained from an FMD simulation model developed for the same region. The optimization model enables more efficient searches for desirable control strategies by considering all strategies simultaneously, providing the simulation model with optimization results to direct it in generating detailed predictions of potential FMD outbreaks.     

An analysis of an early-warning system to reduce abortions in dairy cattle in Denmark incorporating both financial and epidemiologic aspects

Emergency preparedness relies on the ability to detect patterns in rare incidents in an early stage of an outbreak in order to implement relevant actions. Early warning of an abortion storm as a result of infection with a notifiable disease, e.g. brucellosis, bovine viral diarrhea (BVD) or infectious bovine rhinotracheitis (IBR), is a significant surveillance tool. This study used data from 507 large Danish dairy herds. A modified two-stage method for detecting an unusual increase in the abortion incidence was applied to the data. An alarm was considered true if an abortion were detected in the month following the alarm month, otherwise false. The total number of abortions that could potentially be avoided if effective action were taken ranged from 769 (22.9%) to 10 (0.3%), as the number of abortions required to set the alarm increased from 1 to 6. The vast majority of abortions could, however, not be predicted, much less prevented, given this early-warning system. The false to true alarm ratio was reduced when the number of abortions that set the alarm increased. The financial scenarios evaluated demonstrated that the value of an abortion, the cost of responding to an alarm and the efficiency of the actions are important for decision making when reporting an alarm. The presented model can readily be extended to other disease problems and multiple-time periods.     

Most fish destined for fishmeal production are food‐grade fish

Marine fisheries target and catch fish both for direct human consumption (DHC) as well as for fishmeal and fish oil, and other products. We derived the fractions used for each for 1950–2010 by fishing country, and thus provide a factual foundation for discussions of the optimal use of fisheries resources. From 1950 to 2010, 27% (~20 million tonnes annually) of globally reconstructed marine fisheries landings were destined for uses other than DHC. Importantly, 90% of fish destined for uses other than DHC are food‐grade or prime food‐grade fish, while fish without a ready market for DHC make up a much smaller proportion. These findings have implications for how we are using fish to feed ourselves or, more appropriately, how we are not using fish to feed ourselves.     

Energy and resource consumption of land-based Atlantic salmon smolt hatcheries in the Pacific Northwest (USA)

This paper evaluates the resource and energy requirements of six different types of land-based, hatchery production systems located in the U.S. Pacific Northwest: flow-through with a gravity water supply, flow-through with a pumped water supply, flow-through with pure oxygen, partial reuse system, partial reuse with heating, and a reuse system for the production of Atlantic salmon (Salmo salar) smolts. Key parameters used in the evaluation include direct energy, indirect energy, transportation energy, greenhouse gas emissions, and pollutant discharges.Power (electricity and natural gas) and feed energy accounted for the majority of the required energy for all the rearing option evaluated. The sum of the fixed capital and chemicals components accounted for less than 2–12% of the total energy budget for any rearing option. The energy efficiency (energy output/energy input) of the six options ranges from 0.97% for flow-through with pumped supply to 3.49% for the flow-through with gravity supply. The rearing options with the three highest energy efficiencies were flow-through with gravity supply (3.49%), partial reuse (2.75%), and reuse (2.64%).On a kg of smolt produced basis, the six rearing options showed a wide range in performance. The reuse system had the lowest water (2 m³ kg^− 1) and land (0.13 m² kg^− 1) requirements and the third lowest total energy requirement (288 MJ kg^− 1). The partial reuse system had the second lowest total power requirement (276 MJ kg^− 1), a low land requirement (0.21 m² kg^− 1), and moderate water requirements (33 m³ kg^− 1). The partial reuse with temperature control had the second highest total power requirement (657 MJ kg^− 1) and land and water requirements similar to the partial reuse system without temperature control. The flow-through system with pumped water supply had the highest water (289 m³ kg^− 1), land (2.19 m² kg^− 1), and energy requirements (786 MJ kg^− 1) of any of the rearing options. By comparison, the flow-through system with gravity water supply had the lowest energy requirement (218 MJ kg^− 1), a moderate land requirement (0.78 m² kg^− 1), and a high water requirement (214 m³ kg^− 1). The ranking of the six rearing options based capital and operating costs are likely to be quite different from those based on energy, water, and greenhouse gas emissions.     

Short‐term degradation of semiarid grasslands—results from a controlled‐grazing experiment in Northern China

The assessment of grassland degradation due to overgrazing is a global challenge in semiarid environments. In particular, investigations of beginning steppe degradation after a change or intensification of the land use are needed in order to detect and adjust detrimental land‐use management rapidly and thus prevent severe damages in these sensitive ecosystems. A controlled‐grazing experiment was established in Inner Mongolia (China) in 2005 that included ungrazed (UG) and heavily grazed plots with grazing intensities of 4.5 (HG4.5) and 7.5 (HG7.5) sheep per hectare. Several soil and vegetation parameters were investigated at all sites before the start of the experiment. Topsoil samples were analyzed for soil organic C (SOC), total N (N_tot), total S (S_tot), and bulk density (BD). As vegetation parameters, aboveground net primary productivity (ANPP), tiller density (TD), and leaf‐area index (LAI) were determined. After 3 y of the grazing experiment, BD increased and SOC, N_tot, S_tot, ANPP, and LAI significantly decreased with increasing grazing intensity. These sensitive parameters can be regarded as early‐warning indicators for degradation of semiarid grasslands. Vegetation parameters were, however, more sensitive not only to grazing but also to temporal variation of precipitation between 2006 and 2008. Contrary, soil parameters were primarily affected by grazing and resistant against climatic variations. The assessment of starting conditions in the study area and the application of defined grazing intensities is essential for the investigation of short‐term degradation in semiarid environments.     

Marker‐assisted parentage analysis reveals high individual selfing rates in tetraploid red clover genotypes selected for seed yield

Seed yield is a major breeding target in tetraploid red clover. We investigated if marker‐assisted parentage analysis can identify progeny plants with two high seed‐yielding parents in tetraploid red clover and if this technique is more advantageous than traditional half‐sib selection. Parentage analysis was successfully performed on the progeny from the 10% highest seed‐yielding genotypes from a second‐cycle family selection trial: 16.0% of progeny were identified with a high seed‐yielding father. However, progeny plants with two high seed‐yielding parents did not produce more seeds than traditionally selected progeny (27.3 g vs. 30.7 g/plant, respectively). The 10% highest seed‐yielding genotypes displayed on average 2% self‐fertilization. Four genotypes were self‐fertile with individual selfing rates up to 20%. Our results discourage the use of marker‐assisted parentage analysis to improve seed yield in tetraploid red clover when the material has been preselected for seed yield. Breeders should be aware that intensive selection for seed yield in tetraploid red clover may inadvertently lead to selection for increased self‐fertility, which may increase inbreeding in the long term.     

Animal movement varies with resource availability,landscape configuration and body size: a conceptual model and empirical example

Landscape Ecology - Animals must move to find food, shelter and mates, and escape predation and competition. Changes in landscape configuration and resource availability can disrupt natural...     

基于ANUSPLIN的时间序列气象要素空间插值

【目的】介绍ANUSPLIN在黄土高原多沙粗沙区时间序列气象要素的空间插值过程,为相关人员在ANUSPLIN的参数设置、误差分析和协变量要素选择等方面提供参考。【方法】以薄盘样条函数为插值理论,以专用气象数据插值软件ANUSPLIN为实现工具,并引入一个或多个协变量线性子模型,来实现多个气象要素的空间插值。【结果】完成了黄土高原多沙粗沙区时间序列(1980~2000年)多个气象要素月平均数据的栅格化,计算了气象要素随其影响因子变化的关系。【结论】ANUSPLIN以薄盘光滑样条函数为理论基础,引入协变量线性子模型,能较好地提高气象要素空间插值精度,且能反映气象要素随其影响因子变化的比率关系。在大多数情况下,该区模型选择以样条次数为3次的局部薄盘光滑样条函数模型为最佳。温度的空间插值相对比较容易,且误差较小,1995-07平均相对误差为1%;风速、水汽压的误差中等;日照时数和降雨量的误差较大,个别情况相对误差可超过50%。