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971.
Denmark has no free-range wild-boar population. However, Danish wildlife organizations have suggested that wild boar should be reintroduced into the wild to broaden national biodiversity. Danish pig farmers fear that this would lead to a higher risk of introduction of classical swine fever virus (CSFV), which could have enormous consequences in terms of loss of pork exports. We conducted a risk assessment to address the additional risk of introducing and spreading CSFV due to the reintroduction of wild boar. In this paper, we present the part of the risk assessment that deals with the spread of CSFV between the hypothetical wild-boar population and the domestic population. Furthermore, the economic impact is assessed taking the perspective of the Danish national budget and the Danish pig industry. We used InterSpreadPlus to model the differential classical swine fever (CSF) risk due to wild boar. Nine scenarios were run to elucidate the effect of: (a) presence of wild boar (yes/no), (b) locations for the index case (domestic pig herd/wild-boar group), (c) type of control strategy for wild boar (hunting/vaccination) and (d) presence of free-range domestic pigs. The presence of free-range wild boar was simulated in two large forests using data from wildlife studies and Danish habitat data. For each scenario, we estimated (1) the control costs borne by the veterinary authorities, (2) the control-related costs to farmers and (3) the loss of exports associated with an epidemic. Our simulations predict that CSFV will be transmitted from the domestic pig population to wild boar if the infected domestic pig herd is located close to an area with wild boar (<5 km). If an outbreak begins in the wild-boar population, the epidemic will last longer and will occasionally lead to several epidemics because of periodic transfer of virus from groups of infected wild boar to domestic pig herds. The size and duration of the epidemic will be reduced if there are no free-range domestic pig herds in the area with CSF-infected wild boar. The economic calculations showed that the total national costs for Denmark (i.e. the direct costs to the national budget and the costs to the pig industry) related to an outbreak of CSF in Denmark will be highly driven by the reactions of the export markets and in particular of the non-EU markets. Unfortunately, there is a substantial amount of uncertainty surrounding this issue. If hunting is used as a control measure, the average expenses related to a CSF outbreak will be 40% higher if wild boar are present compared with not present. However, a vaccination strategy for wild boar will double the total costs compared with a hunting strategy.  相似文献   
972.
973.
茉莉酸甲酯对采后赛买提杏冷藏品质的影响   总被引:1,自引:0,他引:1  
以新疆赛买提杏为试材,研究茉莉酸甲酯对采后赛买提杏冷藏品质的影响.将赛买提杏置于密闭气调箱内用不同浓度茉莉酸甲酯熏蒸处理绿熟期赛买提杏,处理浓度分别为0(CK),1×10^-4,1×10^-5,1×10^-6 mol/L,处理时间均为24 h,之后放置在(0士0.5)℃条件下贮藏30 d.结果表明,茉莉酸甲酯处理可抑制绿熟期杏果腐烂率的发生,降低呼吸速率,保持较高的维生素C及可溶性固形物含量,有效降低绿熟期杏果实细胞膜透性,浓度1×10^-4 mol/L茉莉酸甲酯处理可以较好保持绿熟期赛买提杏的贮藏品质.  相似文献   
974.
975.
The aim of this study was to evaluate the effect of cloprostenol administration on the blood flow of pre-ovulatory follicle (PF) and corpus luteum (CL), progesterone secretion and pregnancy outcome in buffaloes subjected to AI. The trial was performed on 75 Italian buffaloes at 182 ± 8 days in milk. Synchronized animals were randomly divided into two groups on the day of oestrus: Group T (n = 37) received a 0.524 mg intramuscular injection of cloprostenol and Group C (n = 38) received saline. Ultrasound examinations of the ovaries were performed 5 h after AI on the PF and 10 and 20 days after AI on the CL. Resistive (RI) and pulsatily index (PI) were calculated by colour-Doppler mode in each examination. Blood samples were collected on days 10, 20 and 25 after AI for progesterone assay and 25 days after AI, ultrasonography was performed to assess pregnancy, which was confirmed on day 45. Subjects pregnant on day 25 but not on day 45 were considered to have undergone late embryonic mortality (LEM). Statistical analysis was performed by anova. No differences were found in PF dimensions, CL size and blood flow on day 10 and 20 after AI between treated and control groups. Pre-ovulatory follicle area was higher in buffaloes that resulted pregnant on day 25 after AI compared to those that were non-pregnant (2.13 vs 1.66 cm in pregnant and non-pregnant buffaloes, respectively), while non-pregnant buffaloes showed higher values of RI (0.49 vs 0.30; p < 0.05) and PI (1.0 vs 0.37; p = 0.07) compared to pregnant subjects. Treatment by cloprostenol did not influence pregnancy rate both on day 25 (31/75; 41.3%) and 45 (27/75; 36.0%), progesterone levels and incidence of LEM (4/31; 12.9%). In conclusion, cloprostenol administration at the time of AI does not seem to affect PF and CL blood flow.  相似文献   
976.
A 7-year-old castrated male Whippet developed deep ulcerative skin lesions whilst receiving immunosuppressive doses of prednisolone and cyclosporine for the treatment of immune-mediated haemolytic anaemia. The lesions were determined to be a phaeohyphomycosis, caused by Curvularia lunata. The dog was treated with a combination of systemic antifungals and weaning off immunosuppressants and made a complete recovery. To the authors' knowledge, this is the first case report of the successful treatment of disseminated cutaneous phaeohyphomycosis in a dog.  相似文献   
977.
Clinically, the use of detomidine and butorphanol is suitable for sedation and deepening of analgosedation. The aim of our study was to establish the influence of detomidine used alone and a butorphanol-detomidine combination on brain activity and to evaluate and compare brain responses (using electroencephalography, EEG) by recording SEF90 (spectral edge frequency 90%), individual brain wave fractions (beta, alpha, theta and delta) and electromyographic (EMG) changes in the left temporal muscle in standing horses. Ten clinically healthy cold-blooded horses were divided into two groups of five animals each. Group I received detomidine and Group II received detomidine followed by butorphanol 10 min later. SEF90, individual brain wave fractions and EMG were recorded with a pEEG (processed EEG) monitor using computerised processed electroencephalography and electromyography. The present study found that detomidine alone and the detomidine-butorphanol combination significantly reduced SEF90 and EMG, and they caused changes in individual brain wave fractions during sedation and particularly during analgosedation. The EMG results showed that the detomidine-butorphanol combination provided greater and longer muscle relaxation. Our EEG and EMG results confirmed that the detomidine-butorphanol combination is safer and more appropriate for painless and non-painless procedures on standing horses compared to detomidine alone.  相似文献   
978.
Spin manipulation using electric currents is one of the most promising directions in the field of spintronics. We used neutron scattering to observe the influence of an electric current on the magnetic structure in a bulk material. In the skyrmion lattice of manganese silicon, where the spins form a lattice of magnetic vortices similar to the vortex lattice in type II superconductors, we observe the rotation of the diffraction pattern in response to currents that are over five orders of magnitude smaller than those typically applied in experimental studies on current-driven magnetization dynamics in nanostructures. We attribute our observations to an extremely efficient coupling of inhomogeneous spin currents to topologically stable knots in spin structures.  相似文献   
979.
The aims of this study were to investigate the effect of gradual water deficit stress on some phonological and morphological traits and grain yield of desi and kabuli chickpea cultivars. This study was carried out in 2007 and 2008, to evaluate responses of three chickpea cultivars (Hashem and Arman from kabuli and Pirooz from desi type) under well watering (I1: 70mm evaporation from class A pan), gradual water deficit (12 and 13: 70→90→ 110→130 and 70→100→130mm evaporation from class A pan, respectively) and severe water stress (14: 130mm evaporation from class A pan). Result showed that days to flowering and plant height were decreased, as water limitation increased. This reduction was significant under gradual water stress (I2 and I3) and Severe water deficit (I4), compared with control (I1). There were no significant differences in grain filling period and grain yield among I~, I2 and I3 irrigation treatments. No significant differences in days to physiologic maturity and number of sub branches were recorded among irrigation treatments. Interactions of year×cultivar for days to physiologic maturity, grain filling period and grain yield (P≤0.01) and for days to flowering and plant height (P≤0.05) were significant. The superiority of Arman in producing comparatively greater grain yield could be attributed to higher grain filling period of this cultivar in both years.  相似文献   
980.
economic performance;economic result 经济效益 social benefit 社会效益 socialist market system  相似文献   
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