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161.
Seasonal physiology and growth of planted oaks with implications for bottomland hardwood restoration
New Forests - Afforestation and reforestation of once dominant bottomland hardwood forests in the southeastern United States can provide ecosystem services and wildlife habitat. However, challenges... 相似文献
162.
Chun R Kellihan HB Henik RA Stepien RL 《Journal of the American Veterinary Medical Association》2010,237(7):806-811
163.
Kirsi-Maarit Siekkinen Jaakko Heikkil? Niina Tammiranta Heidi Rosengren 《Acta veterinaria Scandinavica》2012,54(1):12
Background
Farm-level biosecurity provides the foundation for biosecurity along the entire production chain. Many risk management practices are constantly in place, regardless of whether there is a disease outbreak or not. Nonetheless, the farm-level costs of preventive biosecurity have rarely been assessed. We examined the costs incurred by preventive biosecurity for Finnish poultry farms.Methods
We used a semi-structured phone interview and obtained results from 17 broiler producers and from 5 hatching egg producers, corresponding to about 10% of all producers in Finland.Results
Our results indicate that the average cost of biosecurity is some 3.55 eurocent per bird for broiler producers (0.10 eurocent per bird per rearing day) and 75.7 eurocent per bird for hatching egg producers (0.27 eurocent per bird per rearing day). For a batch of 75,000 broilers, the total cost would be €2,700. The total costs per bird are dependent on the annual number of birds: the higher the number of birds, the lower the cost per bird. This impact is primarily due to decreasing labour costs rather than direct monetary costs. Larger farms seem to utilise less labour per bird for biosecurity actions. There are also differences relating to the processor with which the producer is associated, as well as to the gender of the producer, with female producers investing more in biosecurity. Bird density was found to be positively related to the labour costs of biosecurity. This suggests that when the bird density is higher, greater labour resources need to be invested in their health and welfare and hence disease prevention. The use of coccidiostats as a preventive measure to control coccidiosis was found to have the largest cost variance between the producers, contributing to the direct costs.Conclusions
The redesign of cost-sharing in animal diseases is currently ongoing in the European Union. Before we can assert how the risk should be shared or resort to the ''polluter pays'' principle, we need to understand how the costs are currently distributed. The ongoing study contributes towards understanding these issues. The next challenge is to link the costs of preventive biosecurity to the benefits thus acquired. 相似文献164.
Pulmonary hypertension secondary to degenerative mitral valve disease has been recognized clinically for many years in veterinary medicine, and clinical diagnosis of this syndrome in dogs has been enhanced greatly by widespread use of echocardiography and Doppler echocardiography. Medical therapy is now available to treat this clinical complication of mitral valve disease, making timely diagnosis even more important to patient longevity and quality of life. 相似文献
165.
Caryn A. Reynolds Dorothy Cimino Brown John E. Rush Philip R. Fox Thaibihn P. Nguyenba Linda B. Lehmkuhl Sonya G. Gordon Heidi B. Kellihan Rebecca L. Stepien Bonnie K. Lefbom C. Kate Meier Mark A. Oyama 《Journal of Veterinary Cardiology》2012,14(1):193-202
ObjectiveTo identify risk factors for first-onset congestive heart failure (CHF) in dogs with degenerative mitral valve disease (DMVD).AnimalsEighty-two dogs with and without CHF secondary to DMVD were retrospectively assigned to a derivation cohort. Sixty-five dogs with asymptomatic DMVD were recruited into a prospective validation cohort.MethodsVariables associated with risk of CHF in dogs were identified in a derivation cohort and used to construct a predictive model, which was then prospectively tested through longitudinal examination of a validation cohort.ResultsLogistic regression analysis of the derivation cohort yielded a predictive model that included the left atrial to aortic root dimension ratio (LA:Ao) and plasma concentration of N-terminal pro-B-type natriuretic peptide (NT-proBNP). When this model was prospectively applied to the validation cohort, it correctly predicted first-onset of CHF in 69.2% of cases. Analysis of the validation cohort revealed that plasma NT-proBNP concentration and indexed left ventricular end-diastolic diameter (LVIDd:Ao) were independent risk factors for development of first-onset CHF in dogs with DMVD (NT-proBNP ≥1500 pmol/L, odds ratio (OR), 5.76, 95% confidence interval (CI), 1.37–24.28, P = 0.017; LVIDd:Ao ≥3, OR, 6.11, 95% CI, 1.09–34.05, P = 0.039).ConclusionsMeasures of left heart size and plasma NT-proBNP concentration independently estimate risk of first-onset of CHF in dogs with DMVD. These parameters can contribute to the management of dogs with DMVD. 相似文献
166.
Heidi C. Zimmer Hanh Le Thi Duc Lo Jack Baynes J. Doland Nichols 《Agroforestry Systems》2018,92(6):1721-1735
Intense cultivation of annual crops on steep slopes in northwest Vietnam has resulted in widespread and severe erosion. This has led to myriad problems including siltation of dams critical for hydroelectricity generation, and increasing levels of rural poverty due to declining crop yields. The solution to these problems is sustainable land management, in particular sloping land agricultural technologies. Our study focuses on defining, and finding solutions to, a second-order problem: that farmers are reluctant to adopt sustainable land management practices, despite numerous projects demonstrating their effectiveness. Interviews with farmers in northwest Vietnam confirmed that intense corn cultivation on steep slopes provided the majority of income for most households. The financial security associated with growing corn (compared to alternative crops) was the deciding factor in land management choices. However, interviews also revealed that farmers were dissatisfied with growing corn because of low income and high input costs. Farmers’ replies indicated that they thought they had no alternative to growing corn. However, farmers were aware of alternative crops, and were particularly interested in growing grass, fruit trees and timber trees, although few farmers were keen to be first to adopt these alternative species extensively. Further research is required on development of production-to-commercialization chains for alternative crops, and more generally, to find ways to increase farmer financial security during transition to sustainable land management. 相似文献
167.
Chad M. Kooistra Cassandra Moseley Heidi Huber-Stearns Stacy Rosenberg 《Journal of Sustainable Forestry》2018,37(1):56-76
Research about nonindustrial private forest (NIPF) landowners’ perspectives on voluntary conservation-based programs continues to proliferate. However, there is a gap in understanding NIPF landowner perspectives about the social and ecological outcomes of mandatory conservation-based regulations. We sent questionnaires to Oregon NIPF landowners to understand their beliefs about potential outcomes of proposed state regulations that strengthen mandatory riparian buffer habitat protection requirements. Factor analysis and multiple regression techniques revealed the most important variables that influence those beliefs. Overall, respondents believed that the socioeconomic outcomes were negative and the ecological outcomes were neutral or slightly positive. Respondents with more conservative political attitudes who owned larger properties were more likely to believe that the outcomes would be negative. As the importance of maintaining property for future generations and increasing timber productivity increased, respondents believed the potential outcomes would be increasingly negative. As the importance of improving water quality, increasing carbon storage, and improving recreational use on the property increased, respondents believed that the outcomes would be increasingly positive. We discuss management and policy implications, including communication strategies aimed at engaging with NIPF landowners to highlight the purpose and potential outcomes of forest and riparian management regulations. 相似文献
168.
Necroulcerative hemorrhagic gastritis in a cat secondary to the administration of 3% hydrogen peroxide as an emetic agent
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169.
Barnes HL Chrisman CL Farina L Detrisac CJ 《Journal of the American Animal Hospital Association》2003,39(6):547-550
A 6-month-old, female, mixed-breed dog presented for acute, progressive, flaccid paraplegia and bilateral pelvic-limb hyperesthesia. A lymphocytic pleocytosis with 366 mg/dL protein was found on cerebral spinal fluid (CSF) evaluation. Electromyography (EMG) demonstrated positive sharp waves and fibrillations in the left pelvic limb; the M wave of the left sciatic nerve was not obtainable by nerve stimulation. Seizures and dementia began during recovery from anesthesia. Six days after onset of paralysis, the dog was euthanized. Direct fluorescent antibody testing of the brain was positive for raccoon rabies virus. This case demonstrates clinical evaluation, CSF analysis, and EMG in an animal with rabies meningoencephalomyelitis. 相似文献
170.
Equine corneal surgery and transplantation. 总被引:1,自引:0,他引:1
Heidi M Denis 《Veterinary Clinics of North America: Equine Practice》2004,20(2):361-80, vi-vii
Corneal disease is common in equine ophthalmology and requires vigilant monitoring and appropriate therapy to optimize the outcome.Many equine corneal diseases, particularly those that progress rapidly, may benefit from surgical intervention. These include descemetoceles, deep corneal lacerations and ulcers, corneal perforation/iris prolapse, ulcerative keratitis, corneal stromal abscesses, and corneoscleral neoplasia. Indications for corneal transplantation include optical, tectonic, therapeutic, and cosmetic purposes. Corneal transplantation is most often implemented in equine patients for tectonic and therapeutic reasons when a cornea is compromised by corneal stromal abscess, iris prolapse, or neoplasia.This article provides an outline of when to consider surgical intervention for corneal disease, the procedures available and expected outcomes, and how appropriate early surgical intervention can dramatically improve the end result. 相似文献