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  • Energy forests or vineyards?
    237-240
    Views:
    67

    This paper primarily aims at giving an introduction to an alternative opportunity for vineyards owners many of whom have come to a
    decision about elimination of their vineyards. The paper is focusing on the Mátra wine-region as a study area, which is the largest mountain
    wine region in Hungary where more than one third of supported clearing of vineyards have been implemented in the last few years. The
    abandoning of vineyards is explicable in more than one way such as very small average size of land or the increasing mean age of owners
    etc. The fundamental reason is the chronic doubtfulness of the grape and wine market and the low level of overall profitability of production.
    Grape production has a long tradition in this region, thus the disappearance of vineyards caused serious problems in land use through the
    absolute lack of plans for the future. The popularity of biomass production in the press and the biofuel resultant from vine stocks raise
    interest for short rotation forestry within a group of farmers. Short rotation forestry offers a new chance for some farmers to cut oneself adrift
    from the harmful effects of the market of agricultural products.

  • Changes in toxic elements content of soil after sewage sludge treatment in energy willow plantation
    7-10
    Views:
    116

    The primary purpose of our experiment was the solution of municipal excess sludge treatment by a renewable energy resource used willow (Salix viminalis L.) plantation. Tests were carried out to state whether the applied sewage sludge has caused any accumulation of the toxic elements in the studied soil layers, and - based on the results –to see whether the plantation is suitable for the treatment of municipal sewage sludge.
    The excess sludge (sludge before dewatering) is beneficial for the willow, because it contains a 3–5% dry matter and therefore, a lot of water, too. This high water content ensures the high water amount needed for the intensive growth of the willow. On the other hand, the wastewater treatment plant can save the dewatering cost which corresponds to about 30% of the water treatment process costs. The amounts of the sprinkled sewage sludge were calculated on the basis of its total nitrogen content. Treatments were the followings: control, 170 N kg ha-1 year-1 and 250 N kg ha-1 year-1. The mean values of the toxic element concentrations in the sewage sludge did not cross the permitted limits of the land  accommodating.

    The measured toxic element values of the soil were compared to the limits of the 50/2001. (IV.3.) Government Regulation.The  sprinkled sewage sludge on the bases of the total N content did not cause accumulation of heavy metals in the soil and the treated plants were also healthy without any signs of toxicity. 

  • Role of living bacteria and other amendment in early development of maize
    53-56
    Views:
    113

    Different bacteria and wood ash, as a possible micro-nutrient, and liming material, was examined in our experiment on the early growth of corn seedlings.

    The development of renewing energy resources includes the use of energy grasses and energy forests. The intensive land use in forestry and in agriculture may cause the acidification of soils due to the harvest, or leaching of cations. To maintain the sustainability of soils necessary to maintain it’s the buffer capacity, and pH. Beside the lime the wood ash can is one of the most effective sources to provide the sustainability of intensive land use. The soil born micro organisms play a significant role in the maintenance of soil quality. The bio fertilizer, that contains soil originated bacteria (Azotobacter, and Bacillus sp.), was used in the experiments. The plants release several organic acids by their roots lowering the soil pH, and make more available the sparingly soluble minerals. The amounts of released organic matter depend on stress intensity, as the high pH is. The soil life has a significant role to keep the soil conditions on sustainable level, since there are several similarities in nutrient uptake mechanism between the bacteria and higher plants. Advantageous effects of bio-fertilizer were observed in our experiments.

    We came to the conclusion that the use of wood ash is recommended instead of lime for the improvement of acidic soils, on the evidence of its pH increasing effect. The wood ash contains several micronutrients in an optimum composition for forestry and agricultural plants. The solubility of heavy metals is very low; therefore there is no risk to use the wood ash in the agriculture and in the horticulture by our experiments. The retardation of growth at higher ash doses can be explained by the modification effect to the soil pH, as far as the original soil pH was pH 6.8, and when ash was given to the soil, the pH increases to 7.8 pH, that is unfavourable for the uptake of most nutrients.

  • Current Conditions and Opportunities of Biofarming in Hungary
    150-156
    Views:
    85

    The aim of organic farming is not to maximize income, but to achieve optimal product quality. It is completed by the tightest possible material, and energy flow within the farm. Organic agriculture significantly reduces external inputs by avoiding the use of chemo-synthetic fertilizers, pesticides and pharmaceuticals. Instead it works with nature to increase both agricultural yields and disease resistance. Total independence of external resources can not be achieved in Hungary due to the small-scale of organic animal husbandry. Some materials in limited quantities can be purchased from external resources, though the group of these materials is strictly regulated. Organic farming harmonizes with the concept of European multifunctional agriculture, because besides farming, it includes social considerations, as it helps to maintain natural resources and the relationship between people and their environment, and provides a living for those living in the region.
    As regards organic farming the fertility of the soil and the health of vegetation can be influenced in various ways. Farmers have to be highly skilled and able to manage a farm with great expertise. Generally it can be stated that as the use of non-organically produced products is limited, the opportunities to correct failures made by the farmer are minimal, contrary to conventional farming. Farmers must be intent on developing the tightest material- and energy flow. This means that organic farms ideally have both animal husbandry and crop production. This energy and skill demanding system of farming is compensated by state subsidies, growing market share and relatively high prices for organic products.

  • Harmonic development and biodiesel
    91-95
    Views:
    76

    An increased expansion of renewable resources and biodiesel is observed and prognosed, since fossile energy resources are about to run out. Hungary achieved outstanding sunflower years in the recent years in worldwide comparison. In the future, the feedstock of biodiesel production can also be rape besides sunflower.
    According to the concept of harmonious development, the balance between nature, society, economy and human environments is represented by their mutual presumptive character. Research and development need to be aligned into this system. Our aim was to examine the advantages and
    disadvantages of biodiesel production in different environments, using a model to do so. In order to maintain the harmony, the existing resources have to be managed properly, taking the correlations of the system into consideration. Targeted technological developments are necessary, similarly to the improvement of energy safety and efficiency.

  • The use of biogas in energetics
    41-46
    Views:
    101

    In our study we examine the technical facilities of biogas production in the economic environment of a given region. The region can be considered as typical: it has animal farms, a poultry-processing plant with the characteristic problems of environment load and by-product handling. Biogas can be used for energetic purposes, and, in large scale, it can be sold as electric energy. The heat coming from the engine and the generator can be collected in heat exchangers and can be used for preparing hot water and for heating. One third of the gained energy is electric, two thirds are heat. The aim of the local owner and the economic management is to increase the rate of cost-effectiveness in general. We examined the tecnnical and economic conditions of establishing a biogas plant (using data of an existing pigfarm). We planned the biogas plant and calculated the expected investment and operational costs and return.

  • Agri-Environmental Issues in the National Sustainable Development Strategy of the Member States of the Enlarged EU
    346-353
    Views:
    75

    In preparation for the World Summit on Sustainable Development (Johannesburg), almost all EU member-states and some accession countries presented their national strategies for sustainable development (NSSD) during the summer of 2002. Along with other countries, Hungary is only now setting up this important document. Everywhere during the last decade, as in the EU countries, the intention was to involve the environmental problems into other political questions (agricultural, energy and transport policy, etc.). Today the strategy-builders have given up the sectoral view because of difficulties and setbacks, and use a view aiming the problem.
    Agri-environmental issues appear as the elements of sustainability in the national strategies. For example, in accordance with the danger of global warming, the emission of green-house gasses of agriculture; in line with eco-efficiency, the production of renewable raw materials and energy sources originating from agriculture, and, in relation to changing lifestyle, food-safety and the future of biological agriculture will be disputed. With this study, I investigate the main characteristics of sustainable development strategies at both the EU level and at the level of the different member states from an agri-environmental point of view.

  • Reduction possibilities of the production costs of green electricity by using waste heat
    15-20
    Views:
    164

    In my study, I examine the possibility of the reduction of green electric power’s gross production cost. My research topic may have wider considerations, since in the case of CHP technology the utilization of by-product thermal energy is not possible, and the whole production cost devolves upon green electric power. I introduce five options for the use of the heat energy, based on national and international literature and in-depth interviews.

    From the aspect of efficiency, it can be stated that as alternatives, beer production and desiccation may be mentioned, since these two models were appropriate for the utilization of the total quantity of waste heat, and in the given circumstances the lowest reduction of green electric power’s production costs was achieved in these cases utmost.

  • Examination of physical properties of final product and drying properties of combined (convective pre-drying and freeze finish-drying) dehydration method
    5-12
    Views:
    135

    In this study, the effects of freeze drying (FD), hot-air drying (HAD) and combined drying (HAD-FD) on drying characteristics, energy uptake, texture, rehydration and color of carrot were investigated. Results showed that HAD-FD significantly improved the drying time compared with FD under the same operating conditions, and the HAD-FD can reduce the total cost of dehydration. The drying kinetics was described by the Henderson-Pabis and the third degree polynomial models in the case of HAD, FD and HAD-FD. The HAD carrot samples were exhibited shrinkage, case hardening, poor rehydration and brown surface. The FD carrot cubes appeared porous structure, excellent rehydration, soft texture and loose color. The HAD-FD samples were superior to HAD products and was nearer in quality to FD products with respect to appearance, rehydration and surface resistance (texture). Finally, it is concluded that HAD-FD is effective in improving the FD drying rate. However, the combined drying has a small-scale adverse effect on product quality.

  • Research on rheological characteristics of winter wheat varieties
    266-272
    Views:
    113

    The gluten examination test is dominant in Hungary, comparing it to the qualification system of other countries. The determination of alveographic parameters is a basic criterion of winter wheat specifications in some western and southern European countries.
    In the Hungarian and foreign winter wheat qualification systems, in the standards, there is no limit for extensographical parameters. Customers dictate the limits and make their claims as to the specifications.
    We analyzed the alveographic and extensographical parameters of 19 winter wheat varieties grown by the Cereal Research Non-Profit Company in Hungary, and we made a comparison between the results in the challenges of the European Union expectations.
    Examining the information of alveographic and extensographical values, we found that the experimental varieties provide high base to flour types suitable for baking bread and baker’s ware. The GK Élet, GK Petur, GK Memento, GK Csillag, GK Kapos and GK Marcel varieties can meet the market of paste flour needs, too.
    In the variety series, the GK Kalász represents the highest values and the GK Garaboly shows the lowest parameters regarding the alveographic W and the resistance to extension.
    On the basis of relation, we can establish that we can estimate the following little known and used quality indexes: the extensographical resistance to extension with extensographical energy and the alveographic W value, the extensographical energy with the alveographic W value and the alveographic P and L values with the other alveographic parameters.

  • Economic questions of maize production on different soil types
    289-292
    Views:
    103

    The requirements and objective of cultivation are in constant change. For example, different cultivation systems are developed for the purpose of soil protection, the preservation of its moisture content and on soils with various precipitation supply or production site conditions. Traditionally, one of the most important cultivation aims is crop needs. Further cost saving in fertilisation and crop protection can only be achieved by reducing the quality and quantity of production or it cannot be achieved at all. Furthermore, the costs can be significantly reduced by means of the rationalisation of cultivation. Energy and working time demand can also be notably reduced if ploughing is left out from the conventional tillage method. The key requirement of economicalness is to perform the cultivation at the optimal date, moisture level and the lowest possible cost.
    Within production costs, the cost of cultivation is between 3–17%, while they are between 8–36% within machinery costs. It is the vital condition the usability of each technological method to progressively reduce costs. Our evaluation work was carried out with the consideration of the yield data obtained from cooperating farms and the experiment database of the Institute for Land Utilisation, Regional Development and Technology of the Centre for Agricultural and Applied Economic Sciences of the University of Debrecen. Three technological methods (ploughing, heavy cultivator and loosening tillage) were used on several soil types which differ from in terms of cultivability (chernozem, sandy and sandy clay soils) from the economic/economical aspect. We examined the sectoral cost/income relation of maize production as an indicator plant. The maize price during the analytical period was 45 thousand HUF per t. On chernozem soils, the production of maize can be carried out on high income level, while maize production on sandy soils has a huge risk factor. The role of cultivation is the highest on high plasicity soils, since they have a huge energy
    demand and the there is a short amount of time available for each procedure in most cases.

  • Competitiveness of the biomethane opposite with the CHP technology of biogas by definite plant size
    5-9
    Views:
    118

    The biogas sector has never before aroused so much attention as it does today. Combined heat and power (CHP) reliable and cost-effective technologies that are already making an important contribution to meeting global heat and electricity demand. Due to enhanced energy supply efficiency and utilisation of waste heat renewable energy resources, CHP, particularly together with district heating and cooling (DHC), is an important part of national and regional Green House Gas (GHG) emission reduction strategies.

    During my work I am going to use the basic data of a certain biogas plant than I assemble one model from that. Against the CHP technology I am going to plan a biogas cleaning-equipment. During my research it revealed, that in the case of a 1 MW output power plant it is not worthy to deal with biogas cleaning between national conditions. Investigating the quantity of heat recovery in the CHP technology it is obvious, that the net income at 1 m3 biogas is at least 72 times more than the cleaning technology (heat recovery is 0%).

  • Examination of different grain hardness varieties of the grinding technology properties of wheat
    423-435
    Views:
    173

    In the mill industry, the purpose of the grinding technology is to separate wheat endospermium and shell and to recover grists. The most important and the highest energy requirement operation is shredding. Flour quantity and quality produced from wheat depends on the variety of wheat that will be shredded, the type of grinding equipment and the condition used before the grinding. For this reason, during my experiments, I ground two grain structured varieties of wheat in laboratory conditions using a disk grinder, stone grinder and roll grinder in air-dry and conditioned states. We measured the equipment’s performance and the produced grist’s particle size distribution, followed by the calculation of the energy requirements of the grinders. In the grinding experiments we compared the ash contents of the different particle sized grist’s fractions to map the wheat’s particular properties.

  • The effect of gamma irradiation on the germination and growth of Turda Star maize hybrid dry samples
    23-25
    Views:
    58

    In order to study the effects of gamma rays on germination indices i.e. germination index (GI), total germination (GT) and the
    germination energy (GE), of maize hybrid, Turda Star current experiment was conducted. Dry seeds of Turda Star maize hybrid were
    irradiated with 2, 5, 15, 30 and 50 Gy, using a 60Co-gamma radiation source.
    Results showed that gamma irradiation affected all the above mentioned parameters except germination percentage. Total
    germination and germination energy was significantly affected at higher doses of gamma rays. However, increasing doses of gamma
    rays did not have significant effects on seed germination percentage. The other growth parameters showed declining tendency with
    increasing doses of gamma irradiation.

  • Evaluation of automated anaerobic fermentation processes as in the case of mould infected maize
    81-86
    Views:
    146

    In Hungary the renewable energy utilization is planned to achieve 13% by 2020. Biogas production is one of the fields with the largest energy potential. Achieving high efficiency during continuous production despite the mixed and variable composition of input materials is the most common problem which the newly built biogas plants using agricultural raw materials have to deal with. The first experimental reactors at the Department of Water and Environmental Management were built 12 years ago. Control and automation of the four separated bioreactors were executed with ADVANTECH GENIE 3.0 software which granted pre-programmed measurement and points of intervention for pH, temperature, CH4, CO2, H2S, and NH3. The system became out-of-data, therefore in 2010 it has been redesigned and tested. The system is controlled by Compair Proview SCADA (Supervisory Control and Data Acquisition) software running on Linux platforms. The Fusarium infection caused serious yield-losses in cereal production in 2010. In the case of cereal products, which non-utilizable as forage seems an optimal solution is utilizing as biogas raw material. The raw material was based on the Fusarium infected maize. In the recent publication infotechnological and technological experiences of the pilot test period are evaluated as well as direction of future development is defined.

  • Decreasing Energy and Water Use in the Meat Industry
    24-28
    Views:
    61

    The technology supervisions are needed from time to time in order to involve the new research results, experience, new technologies and equipments organising principles into the production and to make it cheaper and with less expenditure to increase the profitability and competitiveness. In the course of our investigation we aimed the analysis of the traditional technologies and improving of it. In this article we detail the heat treatment curing process. We applied the principles of experimental design for the determination the main influencing parameters in the processes. Then we made simulations and modelling in seeking for the environmentally better technology programs. We developed a method for measuring the temperature development of products with small diameter using the similarity theory in unit operation. In the course of the analysis of the heat treatment processes we could state that the heat treatment time can be reduced significantly by decreasing the size of the product and choosing the right ratios among the surface heat transfer intensity, ambient temperature and involving the lethality obtained during the cooling phase. The total sparing were about 10-20%. We solved the problem associated with the sensor placement error using a plastic material (metamid). We establish a curve between the real product temperature and plastic rod temperature by which the monitoring of the process became more accurate. We determine the size modification for different product sizes. In case of curing we observed very similar phenomena. For the determination of the diffusion coefficient we adopted the Ball-method not using in this field till today. We could reduce the excess saltiness and loss of NaCl with about 5%.

  • Using the principles of precision animal husbandry in fishbreeding
    283-287
    Views:
    180

    Aquaculture species such as fish, crayfish, molluscs and plats are a wide range of products, with continuously growing demand worldwide. The reasons for this is that they are cheap and easy-toraise protein sources, thus having significance in food supply especially in developing countries in tropic regions, moreover, the premium category foodstuffs in developed high income countries are also belonging to this category. World annual total production of 164 million tons (2009) are made up of two sources: 1) marine and inland fisheries landings that are stagnating for several years and 2) aquaculture which is growing dynamically with annual 6% rate between 2000–2009. The latter is accounting for nearly 45% of the total supply due to the depleting marine stocks caused by overfishing. Aquaculture is growing continuously also because the production is safe and can
    be planned well. 
    Intensive fish production systems are the representatives of precision animal production, several types exist and widespread worldwide. The modern computerized temperate water recirculation plants with several thousand m3 capacity are widespread also in Europe because they make it possible to produce even the most valuable species whole year round. A key issue in the technical/feeding outlay is to meet the demands of the cultured species the best and the operation of the system is to be safe and cost-effective. One condition for this is intensification: enable to produce more product per unit resource input or effort. The facilities need significant amount of energy, thus renewable energy sources are to be favoured for which Hungary has comparative advantages.

  • Decarbonisation and renewable energies in Hungary
    89-93
    Views:
    118

    The decarbonisation of the power sector signifies reducing its carbon dependency. The aim of several programmes is making a conversion to a sustainable & low-carbon economy. Some of the targets by the EU are legally binding, thus appear in the national legislation and strategies. To meet the objective, we need to use renewable energy soures expansively.

  • Investment funding programs on dairy farms in Hajdú-Bihar County
    11-16
    Views:
    166

    The dairy farming sector needs constant modernization of its buildings, machines and technology in order to maintain its competitiveness and productivity. For the greater scale investments, these companies try to apply for state funds in addition to their own financial sources. Therefore, the investment support system plays a great role by improving the competitiveness and modernity of these farms. In the last 10 years, 7 funding programs were available for dairy farms. In this research, 25 dairy farms were interviewed in Hajdú-Bihar County. The examined farms cover more than 50% of the milk production in Hajdú-Bihar County. The survey questions focused on the investment funding program use of farms between 2007 and 2017 and renewable energy investments including all programs. The results show how many tenders were submitted, how many were successfully evaluated and completed. All farms had at least two successfully evaluated projects. A correlation was found between completed projects by farm size and completed projects. The connection of the modernity index of dairy farms and the completed projects was also shown.

  • The Dg RES generation, storage, utilization and integration program ’1 village – 1 MW’ of the Bükk-Miskolc Region, Phase 1–3.
    233-235
    Views:
    83

    The usage of renewable energy sources (RES) and the increase of energy efficiency could be the solution for the difficulties of the rural impoverished inhabitants. A rural development company with the support of the communities designs the development resources from the EU and the Hungarian State for RES generation and organizes the ’1 village – 1 MW’ RES generation, storage, distribution and usage integration.

  • Evaluation of water balance in apple and pear trees
    193-198
    Views:
    102

    A significant proportion of the aboveground green and dry weight of the plant constitutes the foliage. The canopy is an important factor
    of plant growth. On one hand the canopy absorbs the solar energy, which is necessary for the photosynthesis, on the other hand accumulates
    the absorbed nutrients by the roots, and the most of the water-loss happens through the foliages. The determination of the full canopy is not
    an easy target. In our research we developed a measurement method to determine the leaf area. With the parameters of the examined tree
    (leaf length and maximum width) and the data of ADC AM 100 leaf area scanner we determined the k-value, with which we can easily and
    fast evaluate the leaf surface. Furthermore we defined from the water balance of compensation lysimeters the cumulative transpiration of
    fruit trees and the efficiency of water use of trees.

  • The history and present of public drinking water supply and its regionalisation in Debrecen
    147-151
    Views:
    145

    The public water supply played a major role in the urbanization of Debrecen city, just like in the case of many other cities. We had plenty of water and so we wasted it. However nowadays we experience a considerable decrease in the level of groundwater which causes an increasing need of energy for pumping. Beside the above mentioned the ecological threat and the decreasing water quality are also major problems. This study attempts to draw attention to the possibilities and the future of the regional water supply, by showing the history of the water supply, the sanitation systems of Debrecen and their present day activities.

  • Assessment of Environmental Susceptibility/Vulnerability of Soils
    62-74
    Views:
    84

    Soils represent a considerable part of the natural resources of Hungary. Consequently, rational land use and proper soil management – to guarantee normal soil functions – are important elements of sustainable (agricultural) development, having special importance both in the national economy and in environment protection.
    The main soil functions in the biosphere are as follows: conditionally renewable natural resource; reactor, transformer and integrator of the combined influences of other natural resources (solar radiation, atmosphere, surface and subsurface waters, biological resources), place of „sphere-interactions”; medium for biomass production, primary food-source of the biosphere; storage of heat, water and plant nutrients; natural filter and detoxication system, which may prevent the deeper geological formations and the subsurface waters from various pollutants; high capacity buffer medium, which may prevent or moderate the unfavourable consequences of various environmental stresses; significant gene-reservoir, an important element of biodiversity.
    Society utilizes these functions in different ways (rate, method, efficiency) throughout history, depending on the given natural conditions and socio-economic circumstances. In many cases the character of the particular functions was not properly taken into consideration during the utilization of soil resources, and the misguided management resulted in their over-exploitation, decreasing efficiency of one or more soil functions, and – over a certain limit – serious environmental deterioration.
    Soil resources are threatened by the following environmental stresses:
    – soil degradation processes;
    – extreme moisture regime;
    – nutrient stresses (deficiency or toxicity);
    – environmental pollution.
    Environmental stresses caused by natural factors or human activities represent an increasing ecological threat to the biosphere, as well as a socio-economic risk for sustainable development, including rational land use and soil management.
    The stresses are caused by the integrated impacts of various soil properties, which are the results of soil processes (mass and energy regimes, abiotic and biotic transport and transformation and their interactions) under the combined influences of soil forming factors. Consequently, the control of soil processes is a great challenge and the main task of soil science and soil management in sustainable development.
    The efficient control of these processes necessitates the following consecutive steps:
    • registration of facts and consequences (information on land and soil characteristics, land use, cropping pattern, applied agrotechnics, yields, with their spatial and temporal variability);
    • evaluation of potential reasons (definition and quantification of soil processes, analysis of influencing factors and their mechanisms);
    • assessment of the theoretical, real, rational and economic possibilities for the control of soil processes (including their risk-assessment and impact analysis);
    • elaboration of efficient technologies for the „best” control alternatives (best management practice).
    Scientifically based planning and implementation of sustainable land use and rational soil management to ensure desirable soil functions, without any undesirable environmental side-effects, require adequate soil information. In the last years such data were organized into a computer-based GIS soil database in Hungary, giving opportunities for the quantification, analysis, modelling and forecasting of the studied environmental stresses and for the efficient and scientifically based prevention, elimination or reduction of environmental stresses and their unfavourable ecological and economical consequences.
    Special attention was paid to the assessment of various soil degradation processes, as: (1) soil erosion by water or wind; (2) soil acidification; (3) salinization and/or alkalization; (4) physical degradation (structure destruction, compaction); (5) extreme moisture regime: drought sensitivity and waterlogging hazard; (6) biological degradation; (7) unfavourable changes in the plant nutrient regime; (8) decrease of natural buffering capacity, (9) soil (and water) pollution.
    The actions against undesirable environmental stresses and their unfavourable consequences are important elements of sustainable, efficient, economically viable, socially acceptable and environmentally sound crop production and agricultural development. These are joint tasks of the state, decision makers on various levels, the land owners, the land users and – to a certain extent – of each member of the society.

  • Impact of chronic heat stress on digestibility of nutrients and performance of meat type ducks
    51-55
    Views:
    186

    The aim of the study is to determine the effect of vitamin and mineral supplement under permanently high environmental temperature (30±1 °C) on the digestibility of nutrients, performance and furthermore the composition of duck meat in the growing period. A total of four hundred mixed sex 14 days old Cherry Valley type hybrid ducks were used for the study. Two experimental diets were formulated in the study (control and vitamin E, C and zinc supplemented diet). Based on the results the following conclusions were drown: the antioxidant defence system plays an important role in the reduction of heat stress generated lipid peroxidation process. Feed additives which have direct or indirect antioxidant effects can reduce the negative effects of heat stress on the ducks performance and meat composition. Digestibility of nutrients (Dry Matter, Crude Protein, Crude Fat) was not affected by antioxidant supplementation under chronic heat stress (30±1 °C). The performance was affected significantly by Vitamin C and E and zinc supplementation under heat stress (P<0.05). In the treated group the daily weight gain (dWG) increased and the feed conversion ratio (FCR) was improved significantly (P<0.05). The energy and protein conversion was decreased also significantly (P<0.05).

  • Development alternatives of rural economy
    187-191
    Views:
    100

    Environmental, natural, social and economic processes undergoing both in Europe and in the world predict such a 21st century that is characterised by increasing resource-crisis from both economic and ecological aspects. Therefore, it is very important for Hungary to see what happens to its natural resources, epecially to its agricultural land, water reserves as well as the biodiversity of the local unique flora and fauna. One of the most significant issues of the rural areas of Hungary is whether we can preserve the natural habitats and the various biodiversity of the related species, the favourable biological background of agriculture. In addition, whether we are able to provide high quality food for the country as well as for the broader reagion, whether we are able to produce energy from the resources available as well as to provide sufficient opportunities for the population to  live and work. These can be considered as the most significant issuesof the coming decades which determine the strategy of the Hungarian rural economies in long term.