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141.
Seahorn JL Slovis NM Reimer JM Carey VJ Donahue JG Cohen ND 《Journal of the American Veterinary Medical Association》2003,223(6):832-838
OBJECTIVE: To identify factors significantly associated with an epidemic of fibrinous pericarditis during spring 2001 among horses in central Kentucky. DESIGN: Case-control study. ANIMALS: 38 horses with fibrinous pericarditis and 30 control horses examined for other reasons. PROCEDURE: A questionnaire was developed to solicit information regarding a wide range of management practices and environmental exposures from farm owners or managers. RESULTS: The following factors were found in bivariate analyses to be significantly associated with an increased risk of pericarditis: being from a farm with mares and foals affected by mare reproductive loss syndrome, exposure to Eastern tent caterpillars in or around horse pastures, younger age, shorter duration of residence in Kentucky and at the farm of current residence, being fed hay grown outside Kentucky, a lack of access to pond water, access to orchard grass for grazing, and a lack of direct contact with cattle. In multivariate logistic regression analyses, only variables related to caterpillar exposure and age were significantly associated with fibrinous pericarditis. CONCLUSIONS AND CLINICAL RELVANCE: Results suggest that fibrinous pericarditis in horses may be associated with mare reproductive loss syndrome. Exposure to Eastern tent caterpillars was the greatest risk factor for development of fibrinous pericarditis. The distribution of times of diagnosis of fibrinous pericarditis was consistent with a point-source epidemic. 相似文献
142.
Tan JY Valberg SJ Sebastian MM Davis GD Kelly JR Goehring LS Harland MM Kuebelbeck KL Waldridge BM Newton JC Reimer JM 《The Canadian veterinary journal. La revue veterinaire canadienne》2010,51(9):993-999
Five horses were presented with signs of myopathy along with systemic malaise, hyperfibrinogenemia, hyperphosphatemia, and an elevated calcium phosphorus product (Ca*P). Postmortem findings were consistent with systemic calcinosis, a syndrome of calcium deposition in the tissue of organs including lungs, kidneys, muscle, and heart that has not been previously described in horses. 相似文献
143.
144.
Lindahl Johanna F. Vrentas Catherine E. Deka Ram P. Hazarika Razibuddin A. Rahman H. Bambal R. G. Bedi J. S. Bhattacharya C. Chaduhuri Pallab Fairoze Nadeem Mohamed Gandhi R. S. Gill J. P. S. Gupta N. K. Kumar M. Londhe S. Rahi M. Sharma P. K. Shome R. Singh R. Srinivas K. Swain B. B. 《Tropical animal health and production》2020,52(1):387-396
Tropical Animal Health and Production - Brucellosis is an important zoonosis worldwide. In livestock, it frequently causes chronic disease with reproductive failures that contribute to production... 相似文献
145.
Arthur W. A. M. De Cock Afra Neuvel Günther Bahnweg Johanna C. J. M. De Cock Hermann H. Prell 《European journal of plant pathology / European Foundation for Plant Pathology》1992,98(5):277-289
Thirteen strains ofPhytophthora porri from five different hosts were compared with respect to their morphology, cardinal temperatures for growth, pathogenicity to leek and cabbage and restriction fragment patterns of mitochondrial DNA. Morphology of vegetative growth was rather similar in most isolates. Those characters which differed among isolates showed overlapping variability and could not be used to distinguish groups, with the exception of production of oogonia and sporangia and the antheridium type. Considerable differences were found in restriction patterns of mitochondrial DNA, isolates from the same host mostly showing identical patterns. Isolates from differentAllium species showed relatively similar restriction patterns if compared to the other isolates. Isolates fromBrassica oleracea proved to be a homogeneous group, quite different from the others with respect to restriction patterns, production of sporangia, production of oogonia, antheridium type and pathogenicity. One isolate, CBS 366.59, isolated from and pathogenic toA. porrum, deviated in many characters from the other isolates. It showed the restriction patterns ofPhytophthora nicotianae and also the high cardinal temperatures for growth typical for this species. The sporangia, however, were distinctly non-papillate and the majority of antheridia was of the paragynous type. 相似文献
146.
Capercaillie (Tetrao urogallus L.) populations in Finland have decreased markedly during past decades. One of the assumed reasons is the decreased quality of brood feeding grounds since current forest management transfers mature forests to younger successional stages. We studied how different types of managed Finnish forests offer resources for capercaillie broods by comparing the vegetation and invertebrate fauna of four successional stages in the two most common forest types in Finland, spruce dominated Vaccinium myrtillus (MT) and pine dominated Vaccinium vitis-idaea (VT) type. Forest age class had a significant effect on the cover of bilberry. There was a positive correlation between bilberry cover and the biomass of larvae and of all invertebrates (including all developmental stages) both at the stand and the sample level. Both forest type and age class significantly affected the biomass of larvae. Mature stands and young stands had the highest biomass of larvae in both MT and VT. In both forest site types the sapling stands hosted the smallest biomass of larvae. The results suggest that successional stages that follow clear cutting seriously lowers the food availability for capercaillie chicks and also reduces the shelter that field layer might provide. However, already the young stages that follow sapling phases seem to provide both bilberries and invertebrates so it is quite unlikely that the bilberry abundance alone could explain the dramatic decline of the capercaillie. 相似文献
147.
Rolf Lidskog Johanna Johansson Daniel Sjödin 《Scandinavian Journal of Forest Research》2019,34(4):319-328
Wildfires present a growing risk to many countries, and climate change is likely to exacerbate this risk. This study analyzes how people directly affected by a wildfire understand its causes and consequences, as well as the future risk of wildfires. The point of departure is that social understanding of wildfires has an important influence on the consequences that emerge in the wake of a wildfire. The empirical case analyzed here is the largest forest fire in modern Swedish history, and the material basis of the study is a postal survey to all individuals directly affected by the fire. The results revealed a complex picture of the respondents’ understanding of the wildfire. Even if the fire was human caused, there was little blame toward forest companies and fire departments. Many positive consequences, such as a long-term increase in biodiversity, were attached to the disaster, and there was a belief that organizations will learn from it and take action to limit wildfires in the future. Simultaneously, the majority of the respondents believed that climate change may lead to an increased risk of forest fires in the future. These findings illustrate the complexity of people's perceptions of the fire and its aftermath. 相似文献
148.
E. Carina H. Keskitalo Johanna Liljenfeldt 《Scandinavian Journal of Forest Research》2014,29(5):473-484
The goal of nature conservation is often implemented on productive forest land largely by means of forest certification – a market-driven, voluntary system of third-party verification of the fulfilment of specific goals. This study assesses how certification requirements are being implemented in various organisations in the forest sector at various levels, and the problems and opportunities identified at each level in order to implement the requirements of the standard. Based on interviews with 34 stakeholders in Sweden, the study demonstrates that forest certification is a communication issue: it places great demands on communication or “information logistics” between different parts of the felling and forest management chain, from the top management to the contractor in the field. Integration with environmental performance systems, clarity in the division of responsibility, formalisation of requirements for forest planning and further integration of a culture of continuous improvement and internal reporting could support implementation of the certification system. 相似文献
149.
Effects of elevated concentrations of carbon dioxide ([CO2]) and ozone ([O3]) on photosynthesis and related biochemistry of two European silver birch (Betula pendula Roth) clones were studied under field conditions during 1999-2001. Seven-year-old trees of Clones 4 and 80 were exposed for 3 years to the following treatments in an open-top chamber experiment: outside control (OC), chamber control (CC), 2x ambient [CO2] (EC), 2x ambient [O3] (EO) and 2x ambient [CO2] + 2x ambient [O3] (EC+EO). During the experiment, gas exchange, chlorophyll fluorescence, amount and activity of Rubisco, concentrations of chlorophyll, soluble protein, soluble sugars, starch, nitrogen (N) and carbon:nitrogen (C:N) ratio were determined in short- and long-shoot leaves. Elevated [CO2] increased photosynthetic rate by around 30% when measurements were made at the growth [CO2]. When measured at ambient [CO2], photosynthesis was around 15% lower in EC trees than in CC trees. This was related to a approximately 10% decrease in total leaf N, to 26 and 20% decreases in the amount and activity of Rubisco, respectively, and to a 49% increase in starch concentration in elevated [CO2]. Elevated [O3] had no significant effect on gas exchange parameters and its effect on biochemistry was small in both clones. However, elevated [O3] decreased the proportion of Rubisco in total soluble proteins and the apparent quantum yield of photosystem II (PSII) photochemistry in light and increased non-photochemical quenching in 2000. The interactive effect of CO2 and O3 was variable. Elevated [O3] decreased chlorophyll concentration only in EO trees, and the EC+EO treatment decreased the total activity of Rubisco and increased the C:N ratio more than the EO treatment alone. The small effect of elevated [O3] on photosynthesis indicates that these young silver birches were fairly tolerant to annual [O3] exposures that were 2-3 times higher than the AOT40 value of 10 ppm.h. set as a critical dose for forest trees. 相似文献
150.
Michael J. Beyer John F. Freestone Johanna M. Reimer William V. Bernard Edward R. Rueve 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1997,11(6):356-360
Five thoroughbred foals (4 fillies and 1 colt), all in good to excellent body condition, ranging in age from 4 days to 5 weeks at the time of onset of signs, were presented to 2 Kentucky equine hospitals from 1992 through 1996. All 5 foals presented with tachycardia, hyperhidrosis, diarrhea or a recent history of diarrhea, and muscle rigidity or stiff gait. Four of the 5 foals presented for recumbency, seizure-like activity with opisthotonos, or pronounced extensor muscle rigidity. All 5 foals were hypocalcemic. All foals either died or had euthanasia performed. None responded to oral calcium supplementation. The cause of the hypocalcemia was unknown. Different idiopathic hypocalcemia syndromes may exist in foals. 相似文献