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51.
Godin AC Bengtsson B Niskanen R Tareke E Törnqvist M Forslund K 《The Veterinary record》2002,151(24):724-728
Seven beef cattle from a herd accidentally exposed to acrylamide and N-methylolacrylamide while grazing were observed for eight months. They showed clinical signs of impaired nerve function, mainly in the hindlegs, with varying degrees of weakness and ataxia. The animals were irritable, nervous and hypersensitive to touch. Both pupils of the most badly affected animal were dilated and it had poor pupillary light responses; it also showed signs of axonal neuropathy. Selected haematological and clinical chemistry variables were normal. The severity of the neurological signs was correlated with the concentrations of haemoglobin adducts of acrylamides. The animals recovered substantially after their exposure. The gestations of four of the animals which were in calf proceeded normally. 相似文献
52.
Stina Fjelkner-Modig Håkan Bengtsson Stig Nystrõm Rolf Stegmark 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2013,63(3):102-113
In a six-year crop rotation trial organically and integrated grown vegetables were produced according to current good agricultural practices, taking quality and quantity aspects into consideration. The raw materials assessed focussed on materials used for industrial food production. Nutritional, sensory and agricultural aspects were evaluated. Carrot, cabbage, onion, pea and potato are possible to grow organically for industrial purposes. Depending on crop, the yield was lower (65-90%) for organically grown compared to integrated grown. Cultivation of organic spinach and dill turned out to be difficult due to problems with weed and discoloration. The chemical analyses included pesticide residues, nitrate, glycoalkaloid, dry matter, vitamin C and 25 different minerals and trace elements. Overall, the organically grown crops had higher dry matter content than the integrated grown. However, when examining the data for the different crops contradictory results were noted. No significant differences due to growing system were noticed for vitamin C and the other nutrients except for 4 of the trace elements. The growing system did not influence the sensory properties. 相似文献
53.
Hanna Bergeå Anki Roth Ulf Emanuelson Sigrid Agenäs 《Acta Agriculturae Scandinavica, Section A - Animal Sciences》2016,66(1):25-34
The aim of this study was to investigate if farmer awareness of longevity can explain why the longevity of dairy cows does not increase in Sweden, despite the fact that the genetic trend for longevity in Swedish dairy cattle is positive. In this study, farmers’ decisions were put in the forefront through a qualitative study with semi-structured interviews. The results showed that farmers seemed well aware of biological factors related to cow longevity, that they think the demands on dairy cows have increased over time and that they correlate the higher demands to shorter longevity. However, the farmers had not worked explicitly with longevity of their own herd. There are subjective management decisions behind a culling of a dairy cow, and the reporting of culling reasons does not mirror the farmer’s reasoning behind the decisions, which is a key factor determining longevity. 相似文献
54.
K. Birkhofer F. Arvidsson D. Ehlers V. L. Mader J. Bengtsson H. G. Smith 《Landscape Ecology》2016,31(3):567-579
Context
Hemipteran pests cause significant yield losses in European cereal fields. It has been suggested that local management interventions to promote natural enemies are most successful in simple landscapes that are dominated by large arable fields.Objectives
We study how farming category (conventional, new and old organic fields) and landscape complexity affect pests, natural enemies and biological control services in spring barley. We further analyse if yields are related to pest infestation or biological control services.Methods
The amount of pasture and the length of field borders were used to define landscape complexity around barley fields in Southern Sweden. Arthropods were sampled with an insect suction sampler and predation and parasitism services were estimated by field observations and inspections of pest individuals.Results
Pest infestation was affected by landscape complexity, with higher aphid, but lower leafhopper numbers in more complex landscapes. Aphid predation was higher under organic farming and affected by effects on predator abundance and community composition independent of landscape complexity. Auchenorrhyncha parasitism was neither significantly affected by landscape complexity nor by farming category. Higher aphid predation rates and lower aphid densities were characteristic for organically managed fields with higher barley yields.Conclusions
Our results suggest that it is possible to increase both aphid biological control services and barley yield via local management effects on predator communities independent of landscape complexity. However, the success of such management practices is highly dependent on the pest and natural enemy taxa and the nature of the trophic interaction.55.
Carina Ingvast-Larsson Anja Holgersson Ulf Bondesson† Anne-Sofie Lagerstedt‡ & Kerstin Olsson§ 《Veterinary anaesthesia and analgesia》2010,37(1):48-56
ObjectiveTo investigate the pharmacokinetics and effects of methadone on behaviour and plasma concentrations of cortisol and vasopressin in healthy dogs.Study designRandomized, cross-over, experimental trial.AnimalsNine adult dogs (beagle and beagle cross breeds), four males and five females.MethodsMethadone hydrochloride, 0.4 mg kg?1, was administered intravenously (IV) and subcutaneously (SC) with a crossover design. Drug and hormone analyses in plasma were performed using Liquid Chromatography–Electrospray Ionization–Tandem Mass Spectrometry and radioimmunoassay respectively. Behavioural data were collected using a standardized protocol.ResultsAfter IV administration, the plasma concentration of methadone at 10 minutes was 82.1 ± 9.2 ng mL?1 (mean ± SD), the terminal half-life was 3.9 ± 1.0 hours, the volume of distribution 9.2 ± 3.3 L kg?1 and plasma clearance 27.9 ± 7.6 mL minute?1 kg?1. After SC administration, time to maximal plasma concentration was 1.26 ± 1.04 hours and maximal plasma concentration of methadone was 23.9 ± 14.4 ng mL?1, the terminal half-life was 10.7 ± 4.3 hours and bioavailability was 79 ± 22%. Concentrations of both cortisol and vasopressin were increased for an hour following IV methadone. The observed behavioural effects of methadone were decreased licking and swallowing and an increase in whining after SC administration. The latter finding is notable as it can be misinterpreted as pain when methadone is used as an analgesic.Conclusion and clinical relevanceWhen methadone was administered by the SC route, the half-life was longer, but the individual variation in plasma concentrations was greater compared with IV administration. Increased frequency of whining occurred after administration of methadone and may be a drug effect and not a sign of pain. Cortisol and vasopressin concentrations in plasma may not be suitable for evaluating analgesia after methadone treatment. 相似文献
56.
Landscape simplification promotes weed seed predation by carabid beetles (Coleoptera: Carabidae) 总被引:1,自引:0,他引:1
Weeds constitute major constraints for farmers by reducing crop yield and quality. However, weeds are managed effectively using herbicides, but this may cause harmful effects on human health and the environment. In an experiment on weed seed predation, we tested the biological control potential of carabid beetles to combat weeds in the absence of herbicides. Seeds from three common weed species were placed in cereal fields on conventional and organic farms located along a landscape complexity gradient (area annual crops within 1 km) in two distinct regions in Sweden. Carabid beetles were sampled in the same fields using pitfall traps. Neither carabid species richness nor seed removal was related to organic farming. Seed removal was significantly related to carabid species richness and both carabid species richness and seed removal was higher in landscapes with large total area of annual crops, although the evenness of the carabid communities was lower. The carabid genera with strongest positive relationship to seed removal differed between regions (Trechus in Uppland and Pterostichus in Scania), as did the preference for the different weed seed species. This study concludes that carabid species richness contributes to weed seed predation and that large scale landscape context explains more variation in the carabids’ responses than local farming practices. 相似文献
57.
We studied the effects of excess nitrogen added as nitrate (NO(3) (-)) or ammonium (NH(4) (+)), or both, on mineral nutrition and growth of beech (Fagus sylvatica L.) plants grown at pH 4.2 in Al-free nutrient solution or in solutions containing 0.1 or 1.0 mM AlCl(3). A high external concentration of NH(4) (+) increased the concentration of nitrogen in roots, stems and leaves. The root/shoot dry weight ratio was less in plants grown in the presence of NH(4) (+) than in plants grown in the presence of NO(3) (-). The concentration of phosphorus in the roots was increased and the concentration of potassium in all parts of the plant was decreased by NH(4) (+). A high external concentration of NO(3) (-) caused a decrease in phosphorus concentrations of the root, stem and leaf. Uptake of (45)Ca(2+) by roots was reduced in the presence of high concentrations of NH(4) (+) or NO(3) (-), and a combination of high concentrations of nitrogen and aluminum further reduced the uptake of (45)Ca(2+). Uptake of phosphate ((32)P) and concentrations of phosphorus in root and shoot were increased when plants were grown in the presence of 0.1 mM Al. Exposure to 1.0 mM Al, however, reduced the concentration of phosphorus in roots and shoots and the reduction was greater when plants were grown in the presence of a high external NO(3) (-) concentration. Aluminum binds to roots, and plants grown in the presence of 1.0 mM Al had a slightly higher concentration of aluminum in roots than plants grown in the presence of 0.1 mM Al, whereas the concentration of Al in the shoot was increased 2 to 3 times in plants exposed to 1.0 mm Al. Furthermore, the effects of 1.0 mM Al on uptake of other macronutrients were quite different from the effects of 0.1 mM Al. We conclude that 0.1 mM Al facilitates uptake and transport of phosphorus in beech and that between 0.1 and 1.0 mM Al there is a dramatic change in the effects of Al on uptake and transport of divalent cations and phosphorus. 相似文献
58.
Egenvall A Bonnett BN Olson P Penell J Emanuelson U 《Preventive veterinary medicine》2006,77(1-2):122-136
Our objective was to estimate the 5-year survival to death in insured warmblooded riding horses (as reflected by a life-insurance claim) in horses with or without at least one costly veterinary-care event (VCE) in 1997. We also determined the impacts of gender, age, previous diagnosis of veterinary claim, geographic variables, cost for veterinary claims and life-insurance value upon the survival. The design was a retrospective cohort study using a population of warmblooded riding horses insured in a Swedish animal-insurance company (Agria Insurance, P.O. 70306, SE-107 23 Stockholm, Sweden) in 1997. All horses in this population had insurance both for veterinary-care and life ("complete" insurance reimbursing the insurance holder for most medical problems). We followed two cohorts (2,495 horses with > or = 1 VCE and 15,576 horses with no VCE in year 1997). The median VCE cost in horses with > or =1 VCE was 3,800 SEK, with 10th and 90th percentiles of 1,400 and 11,400 SEK respectively. In total 944 of the 2,495 horses (38%) in the VCE-positive cohort and 2,962 of the 15,576 horses (19%) in the VCE-negative cohort had died (had a settled life-insurance claim) after the follow-up time. An exponential-regression model showed that geldings had a higher risk of claimed death compared to mares and mares had a higher risk compared to stallions. The risk of death increased linearly with age. The risk of death increased with increasing life-insurance value. Horses with previous lameness had the lowest survival, and for high-cost claims this increased risk was not associated with age. 相似文献
59.
Rintisch U Baars J Lahrmann KH 《Berliner und Münchener tier?rztliche Wochenschrift》2012,125(3-4):96-102
The objective of the investigation was to evaluate quantitatively the analgesic efficacy of the Ketamine-Azaperone-general anesthesia during surgical procedures on pigs by nociceptive flexor reflexes (NFR). The study was performed in 30 four to five month old male pigs which were castrated. The NFR was evoked every minute over the N. ulnaris by multiple electrical stimulation consisting of five single stimuli (2 Hz). The reflex response was derived electromyographically (EMG) by surface electrodes placed over the M. deltoideus. The root-mean-square amplitude within the time interval of 80-240 ms after the last stimulus was calculated as measure for the reflex size. The threshold was fixed at 40 microV. Beside electrical NFR recording the surgical tolerance was determined by the traditional interdigital reflex and the defense reaction to defined surgical test stimuli which were incisisions in the scrotal skin, in the tunica vaginalis and in the testis, pulling off the spermatic cord, clamping and cutting off the spermatic cord and final wound disinfection. All surgical pain stimuli were performed simultaneously with the electrical stimuli. After induction of anesthesia the NFR amplitude declined from 3500 microV below the threshold of 40 microV. At 98% of the surgical stimuli without defense reaction were below the reflex threshold. At 93% with defense reactions demonstrated reflex amplitudes above the threshold. When the interdigital reflex was suppressed, 89% of the NFR values fell below the threshold of 40 microV. These findings demonstrate a good correlation of NFR-amplitudes with reactions to traditional controls of analgesia. 相似文献
60.
The present study aimed at describing older persons’ experiences of outdoor environments at nursing homes in Sweden in terms of what factors are important and in what way they are important. Twelve residents and seven next of kin from three nursing homes participated in 16 interviews. Two main themes were identified. The first theme, access to nature and surrounding life, describes the outdoor environment as a means for change and as promoting a feeling of freedom. This theme calls for an inspiring design. The second theme, being comfortable in the outdoor environment, describes how important it is that going outdoors can be something easy and natural, and it calls for a comfortable design. The results are intended to facilitate practical knowledge that is useful to planners, decision-makers and care workers striving to create attractive and useable environments that are part of the daily life of nursing home residents. The themes also exemplify how the outdoor environment at nursing homes can serve as a resource in promoting restoration, a feeling of being at home and positive development late in life. 相似文献