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91.
Transepidermal water loss (TEWL) was measured as assessment of barrier function in house dust mite-sensitized atopic ( n  = 24) and normal ( n  = 21) beagle dogs before and after allergen challenge. Dogs of the two groups were matched for age and housed in the same environment. Ten sites were evaluated including both areas of high and low predisposition to atopic lesion formation. On day 0 (before allergen exposure) and day 3 (3 days after allergen exposure), TEWL measurements were taken using an open-chamber evaporimeter. On day 0, significant differences (one-way ANOVA) were found between normal and atopic dogs in the chin, pinna, periocular region, axilla, antebrachium and thorax. Within the atopic group, a significant increase (one-way ANOVA) in TEWL was found in the axilla on day 3. Such a difference was particularly marked in young dogs (chin, pinna, axilla, antebrachium and groin). Within the normal group, allergen challenge did not change TEWL except for the chin. When atopic and nonatopic sites were compared within the atopic group, a significant difference in TEWL was found on day 0. A two-way ANOVA showed a significant effect of site, a significant effect of time but no site × time (i.e. allergen exposure) interaction. It is concluded that the house dust mite-sensitized atopic beagle dogs used in this study have altered barrier function in 'atopic' areas and that such differences are more evident in young individuals and are aggravated by allergen exposure.  相似文献   
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Vegetative layering of black spruce (Picea mariana [Mill.] B.S.P.) is the principal mode of regeneration for over mature, uneven-aged stands subject to long fire cycles (>300 years) in northeastern Québec, Canada. However, growth response of black spruce layers following disturbance by fire or harvest can be slow, due to a lag of morphological acclimation and potential nutrient limitation. This phenomenon can be accentuated if black spruce is associated with ericaceous shrubs such as Kalmia angustifolia and Rhododendron groenlandicum, which are known to interfere with conifer growth through direct and indirect competition. Such interactions can result in productive stands being converted to unproductive heathlands. It is not known whether these effects of ericaceous shrubs on black spruce are accentuated on low fertility sites, or if the impacts are independent of inherent site fertility. The objectives of this study were to evaluate the effects of ericaceous shrubs on both resource availability and on functional traits of black spruce advance regeneration across a gradient of site fertility (as defined by a site classification system). We monitored black spruce advanced regeneration physiology and soil nutrient availability over two growing seasons on a gradient of ecological site types in northeastern Québec (Canada). The eradication of competing vegetation favored higher soil NH4-N and K availability, with increases of 67% and 28% compared to control conditions, respectively. Black spruce photosynthesis rate (A) and foliar K content were higher in plots where vegetation was eradicated, compared to the control plots, but did not vary among ecological site types. Photosynthesis did not appear to be limited by nitrogen or water relations, but was possibly limited by a deficit of foliar K+, probably resulting from reduced availability following sequestration by the ericaceous root systems. The absence of interaction between inherent site fertility and the eradication of ericaceous shrubs suggests that vegetation management of ericaceous shrubs must be planned independently from the ecological site type.  相似文献   
95.
A 10 year research programme at Lincoln University, investigating the use of Trichoderma species for biological control of soil-borne diseases of vegetable crops, has resulted in the development of two commercial products. Trichodry TM. 6S and Trichoflow TM. 6S based upon Trichoderma hamatum isolate 6SR4, are used to control Sclerotinia lettuce drop disease. The Trichodry 6S product is formulated as a dry flake, which is incorporated into nursery seedling mix and the Trichoflow 6…  相似文献   
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Background

Ireland has long been renowned as a major centre for the breeding, rearing and keeping of horses. Since 2007, however, there has been increasing concern for horse health and welfare standards, and links between these concerns and the structures, governance and funding of the Irish equine industries have been reported. This paper addresses two central issues: firstly the local governance of, trade in and disposal of unwanted horses; and secondly mechanisms employed to improve standards of care given to horses owned by certain communities.

Method

Primary information was gathered through visits to horse pounds run by and on behalf of Local Authorities, to social horse projects, to horse dealer yards, ferry ports, horse slaughter plants and knackeries.

Results

The approach adopted by members of a given group, e.g. ferry ports, is described and differences are highlighted, for example in how different Local Authorities implement the Control of Horses Act of 1986, and how the choice, for example, of disposal route affects the standard of animal welfare.

Conclusions

There is a pressing need for a more centrally mandated and uniformly applied system of governance to safeguard the health and promote the keeping of horses to a higher welfare standard in Ireland. Fundamental to an understanding of why there is insufficient oversight of the keeping and proper disposal of horses is the lack of a comprehensive, integrated system for the registration, identification and tracing of equidae in Ireland.  相似文献   
98.

Background

The objective of this study was to describe aspects of case study herds investigated by the Department of Agriculture, Fisheries and Food (DAFF) in which animal welfare incidents occurred and to identify key performance indicators (KPIs) that can be monitored to enhance the Early Warning System (EWS). Despite an EWS being in place for a number of years, animal welfare incidents continue to occur. Questionnaires regarding welfare incidents were sent to Superintending Veterinary Inspectors (SVIs), resulting in 18 herds being chosen as case study herds, 12 of which had a clearly defined welfare incident date. For each study herd, data on six potential KPIs were extracted from DAFF databases. The KPIs for those herds with a clearly defined welfare incident date were studied for a consecutive four year window, with the fourth year being the ''incident year'', when the welfare incident was disclosed. For study herds without a clearly defined welfare incident date, the KPIs were determined on a yearly basis between 2001 and 2009.

Results

We found that the late registration of calves, the use of on-farm burial as a method of carcase disposal, an increasing number of moves to knackeries over time and records of animals moved to ''herd unknown'' were notable on the case farms.

Conclusion

Four KPIs were prominent on the case study farms and warrant further investigation in control herds to determine their potential to provide a framework for refining current systems of early warning and prevention.  相似文献   
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An estimated 300,000 cases of Lyme disease occur in the United States annually. Disseminated Lyme disease may result in carditis, arthritis, facial palsy or meningitis, sometimes requiring hospitalization. We describe the epidemiology and cost of Lyme disease‐related hospitalizations. We analysed 2005–2014 data from the Truven Health Analytics MarketScan Commercial Claims and Encounters Databases to identify inpatient records associated with Lyme disease based on International Classification of Diseases, Ninth Revision, Clinical Modification (ICD‐9‐CM) codes. We estimated the annual number and median cost of Lyme disease‐related hospitalizations in the United States in persons under 65 years of age. Costs were adjusted to reflect 2016 dollars. Of 20,983,165 admission records contained in the inpatient databases during the study period, 2,823 (0.01%) met inclusion criteria for Lyme disease‐related hospitalizations. Over half of the identified records contained an ICD‐9‐CM code for meningitis (n = 614), carditis (n = 429), facial palsy (n = 400) or arthritis (n = 377). Nearly 60% of hospitalized patients were male. The median cost per Lyme disease‐related hospitalization was $11,688 (range: $140–$323,613). The manifestation with the highest median cost per stay was carditis ($17,461), followed by meningitis ($15,177), arthritis ($13,012) and facial palsy ($10,491). Median cost was highest among the 15‐ to 19‐year‐old age group ($12,991). Admissions occurring in January had the highest median cost ($13,777) for all study years. Based on extrapolation to the U.S. population, we estimate that 2,196 Lyme disease‐related hospitalizations in persons under 65 years of age occur annually with an estimated annual cost of $25,826,237. Lyme disease is usually treated in an outpatient setting; however, some patients with Lyme disease require hospitalization, underscoring the need for effective prevention methods to mitigate these serious cases. Information from this analysis can aid economic evaluations of interventions that prevent infection and advances in disease detection.  相似文献   
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