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31.
Because forest width is thought to be the most relevant metric to ecological communities, it has persisted as the dominant paradigm and focus of management recommendations for riparian forest conservation. Consequently, managers may overlook important effects of the surrounding landscape matrix. We determined if characteristics of the landscape matrix, particularly the amount of urban development surrounding a forest, were better predictors of bird communities than forest width. We sampled breeding-bird communities 3 times each June 2001-2004 in 33 riparian forest sites (69-565 m wide) in Ohio, USA. We examined if bird community structure and composition were more closely associated with forest width or the amount of urban development within 1 km of each forest using canonical correlation analysis. Results indicate that the landscape matrix surrounding these relatively large forest tracts explained >94% of the variation in bird communities compared to <6% explained by forest width. Numbers of Neotropical migrants were negatively associated with urbanization in the landscapes (r = −0.43), whereas residents (r = 0.57) and short-distance migrants (r = 0.41) were positively associated with urbanization. Similar patterns persisted at the individual species level, particularly for Neotropical migrants as 76% of species in this guild were negatively related to urban development. Our findings suggest that the traditional approach to conserving riparian forests is not sufficient and that explicit consideration of the surrounding landscape matrix also should be a key component in conservation efforts. 相似文献
32.
Helene Wahlstr?m Marja Isomursu Gunilla Hallgren Dan Christensson Maria Cedersmyg Anders Wallensten Marika Hjertqvist Rebecca K Davidson Henrik Uhlhorn Petter Hopp 《Acta veterinaria Scandinavica》2011,53(1):9
Background
The fox tapeworm Echinococcus multilocularis has foxes and other canids as definitive host and rodents as intermediate hosts. However, most mammals can be accidental intermediate hosts and the larval stage may cause serious disease in humans. The parasite has never been detected in Sweden, Finland and mainland Norway. All three countries require currently an anthelminthic treatment for dogs and cats prior to entry in order to prevent introduction of the parasite. Documentation of freedom from E. multilocularis is necessary for justification of the present import requirements.Methods
The probability that Sweden, Finland and mainland Norway were free from E. multilocularis and the sensitivity of the surveillance systems were estimated using scenario trees. Surveillance data from five animal species were included in the study: red fox (Vulpes vulpes), raccoon dog (Nyctereutes procyonoides), domestic pig, wild boar (Sus scrofa) and voles and lemmings (Arvicolinae).Results
The cumulative probability of freedom from EM in December 2009 was high in all three countries, 0.98 (95% CI 0.96-0.99) in Finland and 0.99 (0.97-0.995) in Sweden and 0.98 (0.95-0.99) in Norway.Conclusions
Results from the model confirm that there is a high probability that in 2009 the countries were free from E. multilocularis. The sensitivity analyses showed that the choice of the design prevalences in different infected populations was influential. Therefore more knowledge on expected prevalences for E. multilocularis in infected populations of different species is desirable to reduce residual uncertainty of the results. 相似文献33.
Mari J Palviainen Sami Junnikkala Marja Raekallio Seppo Meri Outi Vainio 《Acta veterinaria Scandinavica》2015,57(1)
Background
Non-steroidal anti-inflammatory drugs (NSAIDs) are widely used to treat inflammatory pain in humans and animals. An overdose of an NSAID is nephrotoxic and can lead to acute kidney injury (AKI). Complement activation occurs in several types of renal disorders with proteinuria. The aim of this study was to investigate whether complement system becomes activated in kidneys after a high dose of NSAID. Kidney tissue and urine samples were collected from six sheep with ketoprofen-induced AKI and from six healthy control sheep. The localization of complement proteins in kidney tissue was carried out using immunohistochemical stainings, and excretion of C3 was tested by immunoblotting.Results
The complement system was found to become activated in the kidney tissue as demonstrated by positive immunostaining for C1q, C3c, C4c, C5, C9 and factor H and by Western blotting analysis of C3 activation products in urine samples in sheep with AKI.Conclusions
Our results thus suggest that the alternative complement pathway is activated, and it may contribute to the acute tubular injury seen in the kidneys of NSAID-induced AKI sheep. Inhibition of complement activation may serve as potential therapeutic target for intervention in drug-induced AKI. 相似文献34.
Kirsti Rouvinen Marja Marjoniemi Marianne Eskolin Esa Mäntysalo Seppo Nummela 《Acta Agriculturae Scandinavica, Section A - Animal Sciences》2013,63(1):54-62
Abstract Ninety dried raw blue fox skins having two different dietary backgrounds, saturated fat and fish fat feeding, were submitted to the following experimental treatments: dressing after pelting; control storage at 8 [ddot]C or at -20 [ddot]C; antioxidant diet, storage at 8 [ddot]C or at -20 [ddot]C; butylhydroxytoluene (BHT) drumming, storage at 8 [ddot]C or at -20 [ddot]C; nitrogen gas, storage at 20 [ddot]C; and pickling, storage at 8 [ddot]C. Each storage group contained five skins from both dietary groups. Storage duration for the dried raw skins was approximately one year, during which the changes in their fatty acid compositions were analysed. After the storage period the skins were dressed and the physical characteristics of the leathers were determined. The dietary background of the animals had a significant influence on the fatty acid profiles of the dried raw skins, but it did not affect their fat peroxidation during storage. Moreover, freezing at a temperature of -20 [ddot]C or the antioxidant treatments employed did not prevent lipid peroxidation in the skins. In the pickle-treated skins the changes in the fatty acid profiles were even more pronounced than in the other groups. The only skins in which the fatty acid composition stayed constant were those stored in nitrogen gas. The dietary background affected the breaking load and the elongation at break of the leather. Based on the measured physical characteristic of elongation at break, the quality of the leather decreased when the skins were stored in circumstances involving oxygen. The storage period is recommended to be kept to a minimum time, and storage temperatures above ±0 [ddot]C should be avoided, because of water condensation. The results also emphasize the importance of careful conservation and proper handling of the dried raw skins. 相似文献
35.
Mari Vainionpää Kati Salla Flávia Restitutti Marja Raekallio Jouni Junnila Marjatta Snellman Outi Vainio 《Veterinary anaesthesia and analgesia》2013,40(2):142-148
ObjectiveTo record, with a thermal camera, peripheral temperature changes during different sedation protocols and to relate the results to changes in the rectal temperature.Study designRandomized crossover part-blinded experimental study.AnimalsEight healthy purpose-bred neutered Beagles (two females and six males) weight 14.5 ± 1.6 kg (mean ± SD) and aged 3–4 years.MethodsEach dog was sedated four times. Treatments were medetomidine 20 μg kg?1 and butorphanol 0.1 mg kg?1 (MB) with or without MK-467 500 μg kg?1 (MK). Both drug combinations were administered IV and IM as separate treatments. A thermal camera (T425, FLIR) with a resolution of 320 by 240 was used for imaging.The dogs were placed in lateral recumbency on an insulated mattress. Digital (DFT) and metatarsal footpad temperatures (MFT) were measured with thermography. Thermograms and rectal temperature (RT) were taken before and at 3, 10, 20, 30, 45 and 60 minutes after treatment.ResultsAt 60 minutes after drug administration, MFT was higher (p < 0.001) after MB+MK (34.5 ± 1.1 IV, 34.8 ± 0.5 IM) than MB (31.1 ± 2.9 IV, 30.5 ± 3.6 IM), DFT was higher (p < 0.001) after MB+MK (33.6 ± 1.4 IV, 34.0 ± 0.6 IM) than MB (26.7 ± 1.4 IV, 26.7 ± 2.5 IM), and RT was lower (p < 0.001) after MB+MK (36.7 ± 0.8 IV, 36.9 ± 0.3 IM) than MB (37.5 ± 0.3 IV, 37.4 ± 0.4 IM), with both routes. The change from baseline was greater with MB+MK than MB in all variables.ConclusionsSuperficial temperature changes can be seen and detected with thermography. MK-467 used with MB resulted in increased superficial temperatures and a decline in rectal temperature compared to MB alone.Clinical relevanceThe sedation protocol may influence core temperature loss, and may also have an effect on thermographic images. 相似文献
36.
Kim M. van Schaik-Gerritsen Nico J. Schoemaker Marja J.L. Kik Niek J. Beijerink 《Journal of Exotic Pet Medicine》2013,22(1):70-75
A 2-year-old, male castrated ferret (Mustela putorius furo) was presented with progressive abdominal distention and loss of muscle mass despite normal appetite. Physical examination findings included pale mucous membranes, a prolonged capillary refill time, a pulse rate greater than 300 beats/min, and severe abdominal distention. Abdominal ultrasound showed free abdominal fluid and an enlarged liver with distended hepatic veins and caudal vena cava. During the echocardiographic examination, abnormalities observed included a 2-mm-diameter left-to-right shunting atrial septal defect (ASD) with concurrent severe dilatation of the right atrium and eccentric hypertrophy of the right ventricle with mild pulmonary hypertension. All other echocardiographic measurements were within normal limits. The owner declined treatment, and the ferret was euthanized. Postmortem examination confirmed the ultrasonographic findings. The free abdominal fluid (200 mL) was a non-septic fibropurulent exudate. Decompensated right-sided heart failure due to ASD and exudative peritonitis of undetermined origin were the final diagnoses. To our knowledge, this is the first report of an ASD in a ferret. 相似文献
37.
Kähkönen M Kylli P Ollilainen V Salminen JP Heinonen M 《Journal of agricultural and food chemistry》2012,60(5):1167-1174
Ellagitannins from red raspberries (Rubus idaeus) and cloudberries (Rubus chamaemorus) were isolated by using column chromatography and preparative HPLC. The berry phenolic isolates consisted of 80% (cloudberry) and of 60% (raspberry) of ellagitannins, with raspberries also containing anthocyanins. The main ellagitannins of both raspberries and cloudberries were identified by ESI-MS to consist of the dimeric sanguiin H-6 and the trimeric lambertianin C. Monomeric ellagitannins such as casuarictin in raspberries and pedunculagin in cloudberries were also found. The antioxidant activity of the berry phenolic isolate, ellagitannin isolate (mixture), ellagitannin main fraction (dimer and trimer), and ellagic acid was studied in bulk and emulsified methyl linoleate, in human low-density lipoprotein in vitro, and the radical scavenging activity was studied in the 2,2-diphenyl-1-picrylhydrazyl (DPPH) test. Cloudberry and red raspberry ellagitannins were highly effective as radical scavengers. Berry ellagitannins also showed significant antioxidant activity toward oxidation of both human LDL and methyl linoleate emulsions. However, only weak or moderate antioxidant activity was exhibited by ellagitannins toward oxidation of bulk oil. Thus, ellagitannins contribute significantly to the antioxidant capacity of cloudberries and red raspberries in lipoprotein and lipid emulsion environments, the latter being more relevant for food applications. 相似文献
38.
Suppression of Saprolegnia infections in rainbow trout (Oncorhynchus mykiss) eggs using protective bacteria and ultraviolet irradiation of the hatchery water 下载免费PDF全文
Jouni Heikkinen Marja Tiirola Satu Maarit Mustonen Päivi Eskelinen Dina Navia‐Paldanius Atte von Wright 《Aquaculture Research》2016,47(3):925-939
Since formalin is widely used in prevention of Saprolegnia infections in salmonid fish hatcheries, there is a need for more environmentally safe treatment methods. Therefore, we screened 360 bacterial isolates against their ability to antagonize the growth of Saprolegnia parasitica hyphae in vitro, and best strains were selected according to their antagonistic properties and colonization capability on rainbow trout egg surface. Protective bacterial cultures of Pseudomonas sp. M162, Pseudomonas sp. M174 and Janthinobacterium M169 were tested for prevention of Saprolegnia sp. infections during incubation trials of rainbow trout (Oncorhynchus mykiss) eggs with UV irradiated (400 mWs cm?2) and non‐treated inlet water. UV irradiation of inlet water significantly decreased mortality during the incubation. Lowest mortalities were observed in protective culture treated groups incubated with UV‐irradiated inlet water. UV irradiation increased the dominance of the main bacterial colonizers and variation in the bacterial species diversity between the experimental units. 相似文献
39.
Pascoe PJ Raekallio M Kuusela E McKusick B Granholm M 《Veterinary anaesthesia and analgesia》2006,33(2):97-103
OBJECTIVE: To measure the change in the minimum alveolar concentration of isoflurane associated with three constant rate infusions of dexmedetomidine. STUDY DESIGN: Prospective, randomized, and blinded experimental trial. Animals Six healthy 6-year-old Beagles weighing between 13.0 and 17.7 kg. METHODS: The dogs received each of four treatments; saline or dexmedetomidine at 0.1, 0.5 or 3 microg kg(-1) loading dose given intravenously (IV) over 6 minutes followed by infusions at 0.1, 0.5 or 3 microg kg(-1) hour(-1), respectively. There were 2 weeks between treatments. The dogs were mask-induced with and maintained on isoflurane in oxygen. Acetated Ringer's (5 mL kg(-1) hour(-1)) and saline or dexmedetomidine (each at 0.5 mL kg(-1) hour(-1)) were given IV. Pulse rate, blood pressure, samples for the measurement of blood gases, pH, lactate, packed cell volume (PCV), total protein (TP) and dexmedetomidine concentrations were obtained from an arterial catheter. Sixty minutes after induction minimum alveolar concentration (MAC) was determined by intermittently applying supramaximal electrical stimuli to the thoracic and pelvic limbs. Cardiopulmonary measurements and arterial blood samples were collected before each set of stimuli. Statistical analyses were conducted with analysis of variance or mixed models according to the experimental design. RESULTS: There was a significant decrease in the MAC of isoflurane associated with 0.5 and 3 microg kg(-1) hour(-1) but not with 0.1 mg kg(-1)hour(-1). Serum concentrations of dexmedetomidine were not measurable at the 0.1 mg kg(-1) hour(-1) and averaged 0.198 +/- 0.081 and 1.903 +/-0.621 ng mL(-1) for the 0.5 and 3 microg kg(-1) hour(-1) infusion rates, respectively. Heart rate decreased with increasing doses of dexmedetomidine while blood pressure increased. Packed cell volume increased at 3 microg kg(-1) hour(-1) but not with other doses. CONCLUSIONS AND CLINICAL RELEVANCE: Dexmedetomidine infusions decrease the intra-operative requirement for isoflurane and may be useful in managing dogs undergoing surgery, where the provision of analgesia and limitation of the stress response is desirable. 相似文献
40.
Marja H. Bakermans Amanda D. Rodewald Andrew C. Vitz Carlos Rengifo 《Agroforestry Systems》2012,85(1):85-94
Shade coffee plantations support high numbers of Neotropical migratory birds, but relatively little is known about the structural and floristic attributes used by individual species. From 2005 to 2007, we studied the relationship between habitat characteristics and Neotropical migratory birds in shade coffee plantations in the Venezuelan Andes. Our results indicate that density of migrants was significantly related to both structural and floristic attributes of coffee farms. Specifically, upper canopy foragers were positively associated with number of large trees (>38?cm dbh), tree canopy height, and understory vegetation density. Low canopy and ground foragers were positively associated with numbers of small (8?C23?cm dbh) and medium (23?C38?cm dbh) trees and increased shade cover. Moreover, certain tree species, especially Inga spp., Erythrina spp. and Acnistus arborescens, were important components of habitat for those species that forage in the canopy. For example, our detailed foraging observations showed that Inga trees were used in greater proportion than available throughout plantations by Cerulean Warblers (Dendroica cerulea), a species of high conservation concern. Overall, our research suggests that suitability of coffee plantations for migratory birds may be improved by managing for particular structural and floristic characteristics of plantations. 相似文献