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241.
NRC以前的工作对实验证据进行了总结并且发表了肥育猪的氨基酸对赖氨酸的理想比率。本文研究了 1 997年以来发表的资料 ,以图对肥育猪理想氨基酸比率作一更新 相似文献
242.
Vassiliki Tsioli Lysimachos G. Papazoglou Nikolaos Papaioannou Dimitra Psalla Ioannis Savvas Leonidas Pavlidis Maria Karayannopoulpou 《Journal of veterinary science (Suw?n-si, Korea)》2015,16(1):99-106
Our objective was to evaluate the effectiveness of skin-stretching devices for closing defects on the extremities of dogs. Antebrachial skin defects were created on the limbs of 24 dogs randomly divided into three groups. Skin stretchers included staples and sutures passing through them (group A), sutures and hypodermic needles (group B), and Pavletic device (group C). Wounds on the left were further undermined in all groups. Tension and blood perfusion were assessed. After removing the stretchers on day 3, the defects were sutured and wound healing was clinically scored. Histological variables evaluated were cellular infiltration, edema, collagen orientation, and thickness of epidermis. Significant differences in tension were found among groups (p < 0.0005) and between measurement times for undermined (p = 0.001) or non-undermined (p < 0.0005) wounds. In contrast, blood perfusion values did not differ significantly. Clinical scores for group B seemed to be better than those for groups A and C, but differences were not significant. Primary wound closure using the Pavletic device was not feasible. No significant differences in histological variables were found between groups. Skin stretching with staples or hypodermic needles resulted in successful wound management with minor side effects on skin histology and circulation. 相似文献
243.
The effect of the stage of the ovarian cycle (anoestrus or dioestrus) and of pregnancy on the incidence of gastro‐oesophageal reflux in dogs undergoing ovariohysterectomy 
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下载免费PDF全文 Tilemahos L Anagnostou Ioannis Savvas George M Kazakos Haralabos N Ververidis Dimitra Psalla Charalampos Kostakis Petros Skepastianos Dimitris Raptopoulos 《Veterinary anaesthesia and analgesia》2015,42(5):502-511
ObjectiveTo investigate the potential association of increased blood progesterone (P4) concentrations and/or late pregnancy with the incidence of gastro-oesophageal reflux (GOR), in healthy bitches undergoing ovariohysterectomy under general anaesthesia during anoestrus or dioestrus or during the second half of pregnancy.Study designProspective observational study.AnimalsNinety-four healthy, female, dogs, aged 1–8 years presented for elective ovariohysterectomy.MethodsNon-pregnant animals were classified into group A (anoestrus) (n = 35) if blood P4 concentration was sufficiently low or group D (dioestrus) (n = 26) if blood P4 concentration was sufficiently high. All animals in the second half of pregnancy were classified into group P (n = 33). Acepromazine (0.05 mg kg−1) was administered intramuscularly as preanaesthetic medication, and sodium thiopental (10 mg kg−1, with additional doses if needed) was administered intravenously (IV) for induction of anaesthesia. After endotracheal intubation, halothane (1.1–1.3% end-tidal concentration) in oxygen was used for maintenance of anaesthesia. Lower oesophageal pH was monitored continuously throughout surgery using a pH-measuring probe. Reflux was considered to have occurred whenever pH values of >7.5 (alkaline reflux) or <4 (acid reflux) were recorded. On completion of surgery, carprofen (4 mg kg−1) was administered IV. Further administration of analgesics post-operatively was dictated by visual analogue scale pain scoring.ResultAcid GOR was observed in five of 26 dogs in group D, six of 35 group A, and 12 of 33 group P (p = 0.152). The incidence of GOR in group P approached statistical significance and was higher than the incidence in the combined group A + D (one sided p = 0.044, two sided p = 0.077).ConclusionsIn dogs undergoing ovariohysterectomy, GOR during anaesthesia occurs with a high incidence in dogs in the second half of pregnancy compared to non-pregnant animals during anoestrus or dioestrus.Clinical relevanceMeasures could be taken in such cases to avoid the consequences of potential reflux. 相似文献
244.
Ioannis S. Tokatlidis 《Euphytica》2017,213(4):92
Competition between crop plants, due to resource limitation, is at the root of a considerable yield limitation, a major problem that future agriculture is faced with. Due to inter-plant variation, intra-crop competition causes plant-to-plant interference and unbalanced use of input which decreases possible profit. Acquired intra-crop competition is a priori present in farming due to spatial heterogeneity. Genetically imposed intra-crop competition is due to the plant-to-plant genetic differences, i.e. the intra-species genetic competition in multi-genotypic varieties grown alone, and both the intra- and inter-species genetic competition in intercropping multi-genotypic varieties. In general, high densities accelerate the acquired plant-to-plant variation and intensify the intra-crop competition. Considering environmental diversity, an additional yield gap element is density-reliance. Density-reliant varieties are inefficient in resource use at the single-plant level and present poor results at low densities, accompanied by variation in optimum density particularly in rain-fed agroecosystems. The remedy relies on breeding of varieties that comprise the ‘weak competitor’ ideotype(s) of improved plant yield efficiency in order to mitigate the intra-crop variation and optimise the resource use across variable conditions. To focus on both, selection at nil-competition (widely spaced plants to preclude interference for inputs) is necessary. Selection among spaced plants is further supported by the negative relationship between genotype competitive and yielding ability. The derived density-independent varieties would be capable of taking advantage of the abundance of resources in favourable seasons at low densities that are suitable for dry seasons, approaching the attainable yield across locations and seasons. 相似文献
245.
Ioannis Erkekoglou Nikolaos Nenadis Efrosini Samara Fani Th. Mantzouridou 《Plant foods for human nutrition (Dordrecht, Netherlands)》2017,72(2):176-183
The phenolic content/composition and antioxidant activity of hot/cold infusion and decoction from the leaves of Arbutus unedo were studied for the first time. 1,1-diphenyl-2-picrylhydrazyl (DPPH●), 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) radical cation (ABTS●+), crocin-bleaching, copper-reducing, and liposome accelerated oxidation assays were used for the evaluation of the activity in vitro. In vivo, the extracts were examined for their ability to protect S. cerevisiae cells from H2O2 induced oxidative stress. An on-line high-performance liquid chromatography-DPPH● assay was applied to identify potent radical scavengers and comment on their contribution to the total activity. The addition of leaves to boiling water (decoction) was the most appropriate practice to apply since the highest phenol intake (220.2 mg gallic acid/cup served) was obtained. Additionally, its antioxidant activity was equal or superior to that of the other extracts. Flavonols (~51–61 mg/g dry extract) were the main phenols in all the extracts, with quercitrin accounting for ~20% of the total phenol amount. The on-line DPPH● method verified the high potency of the decoction and indicated as the most active radical scavengers, two galloylquinic acid derivatives and myricitrin, accounting for ~28–45% and ~11–13% of the total scavenging, respectively. Present data may contribute to the future exploitation of A. unedo leaves by the food industry for health-promoting herbal tea preparations and dietary supplements. 相似文献
246.
Air pollutants emissions from traffic are very closely connected to urban air quality, in a local scale, as well as to global
problems like climate change, in a large scale. Road transport air pollutants emissions represent, in most cases, a critical
parameter for a comprehensive and successful understanding of the mechanisms governing the air pollutants concentrations.
Hence, reliable estimations and comprehension of road transport emissions are indispensable in order to set reliable strategies
in the direction of air pollution abatement and management of air pollutants and greenhouse gases emissions. In this framework,
in the present work, the emissions of air pollutants from road transport in Greece will be presented for the whole period
1990–2009 as it was found that a detailed, accurate and reliable emissions inventory was missing. The whole period emissions
variation has clarified the impact of the change in the vehicle fleet, the engine technologies and the fuel quality. The calculated
results have revealed that the age of the vehicles and the corresponding engine technology are the critical parameters determining
the amount of the pollutants emitted. This was mainly observed in both passenger cars and heavy duty vehicles demonstrating
the importance of a renewal programme of the old circulating vehicles in order to set an effective air pollution abatement
strategy. Passenger cars were found to be responsible for the major part of most air pollutants emissions except from nitrogen
oxides and particulates emissions. Heavy duty vehicles contribute more than 66% to nitrogen oxides and particulates emissions.
For the whole time period, all calculated pollutants present a decreasing trend, with the exception of carbon dioxide and
nitrous oxide which increase constantly, ranging from −96% for sulphur dioxide to −1% for PM10. 相似文献
247.
Estimation of nitrogen and phosphorus losses to surface water and groundwater through the implementation of the SWAT model for Norwegian soils 总被引：3，自引：2，他引：3
Ioannis Panagopoulos Maria Mimikou Maria Kapetanaki 《Journal of Soils and Sediments》2007,7(4):223-231
Scope and Background
It is acknowledged that diffuse sources cause the most important nitrogen (N) and phosphorus (P) losses to the river system and substantially enrich the groundwater in nitrates. These losses arise primary from agricultural activities mainly fertilizer applications, and they are determined by soil attributes. In cold climates, winter conditions and freezing of soils may influence the infiltration capacity of the soil and thereby can have a serious effect on the partitioning of excess precipitation and subsequently on the soil and nutrient transportation. The purpose of this article is to investigate the behaviour of six widespread and different textured soil types, on nutrient (N, P) losses under cold climate conditions. The investigation was conducted in the Norwegian Vansjø-Hobølv catchment through the application of a physical model named Soil and Water Assessment Tool (SWAT), taking into consideration the additional aspect of freezing soils during winter, which distinguishes Scandinavian from other European soils.Methods
SWAT is a physical river basin model that was developed for the U.S.D.A. Agricultural Research Service, by the Blackland Research Center in Texas. In the current modeling approach the catchment was divided into 43 Hydrologic Response Units (HRUs) which consist of different combinations of the existed landcover and soil types. Nitrogen and phosphorus losses arising from these HRUs were estimated for the period 1990–2001 through the simultaneous simulation of water and sediment processes that are closely linked to the nutrient processes. The model took into account soil temperature in order to quantify water and nutrient transport to deeper layers, considering negligible downward movement when the soil temperature was under 0°C. It also simulated the aboveground development of the snowpack and the snowmelt processes on a daily basis. The six different soil types were distinguished in two groups according to their similarity in texture and other physical properties, one group of fine-textured soils and a group of coarse soils. The results were evaluated for different crop cultivations (barley, oats and wheat) of the aforementioned soils. Finally, the model was calibrated and validated by comparing predicted results with measured data.Results and Discussion
Fine-textured soils caused significant runoff, sediment, total nitrogen (TN) and total phosphorus (TP) yields to the river system while coarser soils were characterized by high water drainage and nitrates leaching. The first soil group caused a mean of 517 mm of runoff in annual basis, 200 mm higher than this arising from coarse soils. Moreover, 3 tonnes of sediments per hectare, 24.6 kgN/ha and 0.54 kgP/ha were lost annually to surface water from fine soils while the average respective losses originating from coarse soils were only 1.3 tn of sediments/ha, 13.6kgN/ha and 0.17kgP/ha. The sensitivity ranking of the soil types to TN and TP losses was silty-clay-loam>silty-loam>clay>loamy>sandy-loam>sandy. An average of 277 mm of water was percolated annually under the bottom of the soil profile in coarse soils causing the additional leaching of 5.6 kgN-NO3/ha whereas the losses originating from fine-textured soils were 153 mm and 2.5 kg/ha respectively. According to their sensitivity in nitrates leaching, the six soil types were ranked in the following order: sandy>loamy>sandy-loam>silty-loam>silty-clay-loam>clay.Conclusions and Perspectives
The results showed that even though under cold climate conditions, with monthly periods of average air-temperatures below zero, the overall amounts of annual TN and TP losses to surface waters as well as nitrates leaching to groundwater were considerable. This demonstrates that the cold climate conditions did not affect the long-term behavior of the six widespread Norwegian soils, which on an annual basis responded similarly to the respective European soils. According to the model’s estimations, infiltration with N and P transport still occur in wintertime, and comparing to other studies that reported similar results, different possible explanations were considered. The results demonstrate the need of considering the soil differentiation in Scandinavian countries similarly to the rest of Europe in order to apply mitigation measures against nitrogen and phosphorus losses to surface and groundwater.248.
仔猪饲料中添加的血浆成分有提高仔猪的采食量和促生长作用,这是毫无疑问的。通常血浆蛋白粉可使仔猪的采食量提高20%～60%,特别是在 相似文献
249.
奶酪制品为我们配制断奶仔猪饲料提供了具有潜在价值的乳产品,但是在评价这些关键点前我们需要决定使用哪种来源的乳清粉。乳清粉现已不是新型的饲料成分,而它在仔猪日粮中的有利影响也并不难理解,特别是在欧洲。一位在欧洲和美国做研究工作的学者已清楚地证明,当使用像乳清粉之类的乳制品时,以谷物和大豆类为基础的仔猪日粮能促进仔猪的生长(如图1所示)。通过这些实验并根据大量的商业性试验得到,包括简单日粮中超出30%的乳清粉一致地能促进断奶3周左右的小猪的生长性能50%多。断奶后这种影响更加明显。最近,研究证明喷雾型乳清粉能阻止致… 相似文献
250.
给断奶仔猪饲喂颗粒料加粉料的混合料 总被引：2，自引：0，他引：2
断奶仔猪的日粮多为颗粒料。当然,这有很多理由,不仅仅是因为采用颗粒料可减少饲料浪费并提高养分的消化率。采用颗粒料的结果就是饲料利用率可得到改善,并且因而生长率也可在断奶后最初几周这一关键时期内改善5～15%。美国300多万头断奶猪今年不再简单地接受颗粒饲料,它们在进入保育舍内最初几天内被喂给一种颗粒料和粉料的混合料。 相似文献