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61.
62.
Methods to reduce pathogen microorganisms in manure   总被引:2,自引:0,他引:2  
Manure always contains microorganisms originating from faeces, bedding material, feed residues, etc. A small percentage of the enteric microorganisms are pathogens, some of them being obligate parasites so that they can no more multiply outside of their hosts. If these pathogen microorganisms gain access to other sensitive host, water or vegetation, there will be health risks for animals or human. Some microorganisms in manure can increase the risks for deterioration of fodder if manure should contaminate fodder and these microorganisms can be secreted into raw milk. In particular, the cheese industry can encounter difficulties from butyric acid producing clostridia present in manure.

The reduction and controlling of microorganisms can be done by microbiological, chemical or physical methods. The efficiency as well as the advantages and disadvantages of these methods will be discussed. Some methods may give other beneficial products, thus providing novel opportunities for new sources of farm income. All methods do require investments and have operational costs thus the selection becomes dependent f. i. how long animal breeding will be practised. Some methods fit better for seasonal or temporal use. The method selected depends also on the form of the manure as well as on the size of the animal unit.

The hygiene control claims of EU will be critically discussed.  相似文献   

63.
64.
The importance of ecosystem services for human well-being has been highlighted by several recent environmental studies and assessments. These assessments provide useful information for urban green management, but they largely exclude various nuisances and losses produced by ecosystem functions. Lack of attention to these ecosystem disservices may seriously hamper environmental management in general and urban green management in particular. Ecological, social and technological changes will affect both what kind of disservices will emerge and how they will be experienced and managed. Especially in urban areas, environmental, social and technological changes spanning from global to local levels are continuously altering urban ecosystems. Our ways of perceiving and valuing ecosystem functions are also undergoing rapid change. Here we discuss the concept of ecosystem disservices from the perspective of northern European urban ecosystems. It is concluded that perceptions about ecosystem disservices have an increasing influence on how urban green areas are experienced, valued, used, managed and developed.  相似文献   
65.
Autolysis of protein isolates from vascular bundle and inner tuber tissues of potato (Solanum tuberosum) enhanced the inhibition of the angiotensin converting enzyme I (ACE), a biochemical factor affecting blood pressure (hypertension). The physiological age of the tuber affected the strength of ACE inhibition, the rate of its increase during autolysis, and the tuber tissue where ACE inhibition was most pronounced. The highest inhibitory activities (50% reduction in ACE activity achieved following autolysis at a protein concentration of 0.36 mg mL (-1)) were measured in tubers after 5-6 months of storage prior to sprouting. The rate of ACE inhibition was positively correlated with protease activity in tuber tissues. Amendment of the autolysis reaction with protein substrates from which bioactive ACE-inhibitory peptides may be released, for example, a purified recombinant protein or a concentrate of total tuber proteins, also enhanced ACE inhibition. Many tuber proteins including aspartic protease inhibitors were degraded during autolysis. The data provide indications of differences in the enzymatic activities confined to different parts of the potato tuber at different physiological stages. Results suggest that native enzymes and substrate proteins of potato tubers can be utilized in search of dietary tools to manage elevated blood pressure.  相似文献   
66.
Through the recent increases in abundance, pikeperch (Sander lucioperca) has not only become a valuable target for recreational and commercial fishing, but also the most important top predator in many lakes. Generally oligotrophic Lake Höytiäinen (283 km2) sustains one of the most economically valuable pikeperch stocks in Finland, and its annual fisheries yield (up to 5.5 kg/ha) is exceptionally high among Finnish lakes. Here, we followed seasonal movements of fish using conventional tagging, and studied short‐term and long‐term diet of pikeperch by stomach content and stable isotope analyses to examine if the movements were motivated by prey availability. A clear seasonal migration pattern was observed: in summer, 80% of the tag recoveries were obtained from the shallow and mesotrophic northern and western areas, whereas in autumn and winter, the deep and oligotrophic southern area dominated in the recaptures. The diet of pikeperch consisted of the most abundant fish species in the lake, perch (Perca fluviatilis) and roach (Rutilus rutilus), as well as insects. Stable isotope analysis indicated a shift from a dominance of pelagic food sources to littoral food sources during the growing season of pikeperch. Our results suggest that the pikeperch migrations facilitate efficient material transfer from the mesotrophic part while the deeper and oligotrophic part offers a favourable overwintering environment.  相似文献   
67.
Tuber shape is a genetically determined, important varietal characteristic that is also influenced by environmental factors. In this study, the overall dimensions of tubers of two potato cultivars (Van Gogh and Yukon Gold) were determined using a triaxial ellipsoid model that was found to encompass the main varietal differences. The more detailed surface features were captured using a spherical-harmonics series representation for the residual undulation. The method was then applied to four additional cultivars (Bellona, Lady Rosetta, Pito, and Sabina). Modelling the undulation of tuber surface in addition to the overall dimensions indicated that cultivars differed in the global shape and, in specific cases, also in the surface undulation of tubers. The new, improved method for modelling tuber shapes can thus capture and distinguish the overall three-dimensional shape and irregularities caused by growth conditions and other factors. It is envisaged to be useful for quantitative genetics approaches aiming to resolve the relative impact of different genes on tuber shape, as well as for various machine vision and other applications.  相似文献   
68.
Lines of potato cv. Pito transformed with the P1 gene ofPotato virus Y (PVYo) in sense or antisense orientation were evaluated for resistance to PVY in the field in 1997 and 1998. The transgenic resistance fully protected the crop from infection with PVYo transmitted by aphids in both years. These plants were not resistant to the field isolates of the PVYN strain group, which is in agreement with our greenhouse experiments. Consequently, several transgenic lines produced higher yields than the nontransgenic cv. Pito plants. These results showed that the P1 gene-mediated resistance provides significant benefits under conditions were the incidence of infections and damage by PVYo are considerable.  相似文献   
69.
The deer ked (Lipoptena cervi) is a haematophagous parasitic fly of cervids that spread to Finland in the early 1960's. Presently its northern distribution limit lies at approximately 65°N and it is gradually spreading northwards. In Finland the principal host species has been the moose (Alces alces), but the deer ked is about to establish contact with another potential host, the semi-domesticated reindeer (Rangifer tarandus tarandus) causing possible threats to reindeer health and management. The aim of this study was to investigate if the deer ked would have an influence on the welfare of the reindeer. Eighteen adult reindeer were divided into three experimental groups: the control group and two infected groups with 300 deer keds per reindeer introduced in August-September. One of the infected groups was treated with subcutaneous ivermectin in November. To gather comprehensive data on potential health hazards caused by the deer ked a wide array of physiological variables was measured during and at the end of the experiment in December. The keds caused no clear changes in the complete blood count, plasma clinical chemistry, amino acids, endocrinology, energy stores, enzyme activities or tissue fatty acid profiles of the host. The haematological, clinical chemical and endocrinological values displayed changes that could be related to the seasonal physiological adaptations of the species. In conclusion, at the duration and intensity of infection that were employed, the effects of the deer ked on the measured physiological variables of the reindeer were insignificant.  相似文献   
70.
  • 1. European eel (Anguilla anguilla) is recognized as a critically endangered species in the northern hemisphere. Threats such as overfishing or pollution are well known as risks for eel populations. However, much less is known about the impact of introduced fish on European eels. In particular, introduced large‐bodied predators could become new predators to eels.
  • 2. The potential impact of European catfish (Silurus glanis L) on an eel population in the Camargue, southern France was studied using a combination of stable isotope and gut content analyses.
  • 3. Only large‐bodied catfish (>500 mm) can consume numerous fish prey. However, catfish mostly consumed crayfish (Procambarus clarkii), these prey items being found in 79% of the guts of the largest individuals. Eel was absent from the dissected catfish guts. A mixing model based on Bayesian inference revealed that catfish diet included only 5% (0–8.5%) of marine sources (both eel and mullet).
  • 4. While local economic interests prompted ecological studies to assess whether catfish exerted a new and strong predatory pressure on eel, this study found that European catfish behaved as an opportunistic omnivore, and as such was not a direct threat as a predator on eel populations in the Camargue. Copyright © 2011 John Wiley & Sons, Ltd.
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