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Some strategic aspects of animal protein production
11-19Views:300The access to food shaped human societies and dietary models throughout the history of mankind. Animal protein consumption became a part of human culture. Data are presented showing the relationship of daily calorie and animal protein consumption as affected by capita GDP changes. Examples are presented how genetic improvement of animal and fodder plants influenced the resource efficiency and the overall environmental footprint per unit product. The two examples presented are: the dairy industry of the USA the 1944 and 2007 situation, and the Hungarian broiler chicken sector considering data relevant to 1930, 1960 and 2010. In both cases, dramatic improvements in resource efficiency could be demonstrated. The agricultural area required to animal feed production was reduced by more than 80% in both cases per unit product. Future possibilities are briefly discussed, referring to the still unutilized land reserves of the Globe, the new evolving technologies in progress inclusive the CASPR/Cas 9 genetic editing methods.
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Effect of Silver willow “Russian olive” (Elaeagnus angustifolia) on extensive sheep management
157-162Views:221We carried out a study in the Karcag Research Institute, which affected the areas of narrow-leaved silver willow. In the framework of this research, we performed Balázs's coenology, and thus established the degree of Borhidi degradation, which resulted in the fact that the areas of the silver willow were degraded practically irreversibly, the diversity of the grassland has decreased. We consider it very important to study these grassland areas of silver willows, as they can provide an additional fodder base for sheep grazing, which will also increase the sustainability of the grassland. The obtained soil analysis results show that the soil samples of the silver willow areas are richer in nitrogen (p-value: 0.006) and phosphorus (p-value: 0.003) than the examined control area.
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Effect of Irrigation on the Yield and Quantity of Potato Varieties
53-61Views:363In Hungary, the growing area of potato area dropped dramatically in the last few decades. Additionally not only are we lagging behind Western European countries as regards yields, but the competitiveness of production is further decreased by the great alternation in yields from year to year, unpredictable market conditions, poor consumption habits and, often the lack of quality products.
The experiment was carried out at the experimental site of the University of Debrecen, Farm and Regional Research Institute, at Látókép. In our experiment, we examined the yield and some quality parameters of 9 medium-early varieties in large parcels. Of the examined varieties, 3 are of Dutch, and 6 are of Hungarian breeding.
The experiment was set up in 2003 and 2004, in two years of significantly different precipitation, on 50 m2 parcels on calcareous chernozem soil after winter wheat as a forecrop in both years. The 9 varieties were examined in 4 repetitions in randomized blocks, from which two repetitions were irrigated, and two were non-irrigated.
We examined the yields of the varieties, the distribution of tubers according to size and their percentages, and the changes in specific parameters of quality and inner content due to irrigation. We studied the dry matter content, the starch content, the underwater mass, the amount of reducing sugars, and the colour index of frying of the tubers.
In Summary, it can be stated that among the agrotechniques, year effect, variety and irrigation factors have considerable impact on potato yield quality and quantity. However the effect of irrigation depends on the crop year. In a draughty year, like in 2003, irrigation could increase the yield by 10%, while in a more favourable wet year, the improving effect of irrigation was low. -
Presentation of winter flower-dub lesions of peach varieties originating from different growing areas
70-73Views:166Although there are many critical points in peach production, in Hungary, winter frost damage is one of the most significant. Serious winter frost damage on the Hungarian Great Plain was the focus of our experiments. The adequate growth and the most adaptable varieties are determining factors in peach production. In our experiments, we compared three growing areas (Siófok, Sóskút, Szatymaz) and four different varieties (Suncrest, Redhaven, Meystar, Michellini). Throughout these growing areas and with varieties, we wanted to demonstrate the differences in the frost damage values of the flower buds in 2005 and 2006.
In the course of the statistical trials, we found that the difference between the varieties is significant (table 2). The most tolerant variety as for frost tolerance is the ‘Michellini’ variety, and the worst is the ‘Suncrest’ variety. We also found that these data are significant. When we examined the varieties according to their growth, we got the same results (table 3). We determined that the differences between growth are significant and related to these four varieties and the two years (2005-2006), that frost damage was the highest at Szatymaz, and that it was the lowest in Sóskút. -
Validation of the competence profile of agri-environmental engineering bachelor course
63-71Views:325As member of the European Union, the development if the Hungarian agriculture is determined by the Common Agricultural Policy. After the reform of the Common Agricultural Policy in 2003, the environmental protection has got a crucial function. The constant changing role of agriculture has reacted students in higher education. For firms connected to agriculture, human resource management based on competency has an important role in custody of competitiveness. One of the most important goals of firms is to supply the demands of their economic partners. To make it successfully, highly qualified human resource is required. The quality of human resource is determined not only by its qualification, language skills, professional experience, and practise, but extant competencies that can also be developed. To choose the expectant employee, it is not enough for them to have intelligence and proficiency; it is also decisive to examine their particular competencies. All of these will define the employee’s
achievement that will definitely contribute to the success of the enterprise. Basically, closer cooperation is needed between higher education institutions and employers to achieve this goal. At the same time, the higher education institutions can revise their training systems considering the actual requirements of labour market, and accordingly, they can form syllabus in a way to train auspicious experts. In this article examination of the requirements of labour market for graduates from agri-environmental engineering bachelor course is presented. -
Challenges and limtations of site specific crop production applications of wheat and maize
101-104Views:244The development and implementation of precision agriculture or site-specific farming has been made possible by combining the Global Positioning System (GPS) and the Geographic Information Systems (GIS). Site specific agronomic applications are of high importance concerning the efficiency of management in crop production as well as the protection and maintenance of environment and nature. Precision crop production management techniques were applied at four locations to evaluate their impact on small plot units sown by wheat (Triticum aestivum L.) and maize (Zea mays L.) in a Hungarian national case study. The results obtained suggest the applicability of the site specific management techniques, however the crops studied responded in a different way concerning the impact of applications. Maize had a stronger response regarding grain yield and weed canopy. Wheat was responding better than maize concerning plant density and protein content performance.
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Evaluation of Hungarian show-jumping results using different measurement variables
81-85Views:424The aim of the study was to compare different fitted models for show-jumping results of sporthorses and to estimate heritability and repeatability value. Show-jumping competition results collected between 1996 and 2011 were analyzed. The database contained 358 342 starts of 10 199 horses. Identity number, name and gender of the horse, rider, competition year, the level and location of the competition and placing were recorded in the database. To measure performance of horses, placing, number of starters and competition level were used. Competitions were categorized into five groups based on their difficulty level. The used repeatability animal model included fixed effects for age, gender, competition place, year of competition (and competition level in case of non-weighted measurement variables), and random effects for rider, animal and permanent environment effect. Variance components were estimated with VCE-6 software package. The goodness-of-fit of the models was low and moderate. Heritability and repeatability values were low for each measurement variables. The best goodness-of-fit model the weighted square root of placing resulted the highest heritability and repeatability value h2=0.074 and R=0.296.
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Comparative analisis of different canopy forms of sweet cherry cultivars
19-22Views:263The Hungarian sweet cherry production has been changed significantly in the last decades, which primarily resulted in growing intensity of the orchards. Due to the favourable selling prices of the sweet cherry many growers see good prospects in this fruit. One of the key questions of their success is the choice of the most proper canopy form according to the growing conditions, which facilities the efficient completion of annual technological operations.
In new orchards almost exclusively variations of spindle canopies are established, although many other crown forms are used all over the world. From the point of the domestic sweet cherry production it is indispensable to get information about these canopies, and compare with the prevailing crown forms with central axis.
In our experiment we compared free spindle and bush canopies in the Horticultural Experimental Farm of the University of Debrecen in 2013. According to our results it can be stated that the bush canopy can be described with more balanced growth, which makes easier to maintain the vegetative and generative balance. Another positive characteristic of the bush canopy is, that the height of the trees is smaller with 50% compared with the free spindle, which makes the pruning and the harvest easier.
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The Effect of Year and Irrigation on the Yield Quantity and Quality of the Potato
12-16Views:458In Hungary, the growing area of potato area reduced dramatically in the last few decades, additionally we are lagging behind the Western European countries as regards yields and the competitiveness of production is further decreased by the great alternation in yields from year to year, the unpredictable market conditions, bad consumption habits and many times unfortunately the lack of quality products.
The ecological and climatic conditions of Hungary are not everywhere suitable for potato, in the area of Debrecen the amount of rainfall was lower, and the monthly average temperature was higher than the requirement of potato in its growing season in 2002 and 2003.
The experiment was carried out at the experimental site of the University of Debrecen, Farm and Regional Research Institute, at Látókép. In our experiment we examined the yield and some quality parameters of 8 and 9 medium-early varieties in large parcels in 2002 and 2003 respectively. Out of the examined varieties 3 are of Dutch, and 6 are of Hungarian breeding.
The experiment was set up on 49.5 m2 parcels on calcareous chernozem soil after winter wheat as a forecrop in both years. The 9 varieties were examined in 4 repetitions in randomized blocks, out of which two repetitions were irrigated, and two were non-irrigated.
We examined the yields of the varieties, the distribution of tubers according to size and their percentages, and the changes in specific parameters of quality and inner content due to irrigation. We studied the dry matter content, the starch content, the under-water mass, the amount of reducing sugars, the colour index of frying and the element contents of tubers.
Summing up, it can be stated that among the agrotechnical year effect, variety and irrigation factors have considerable impact on potato yield quality and quantity. On the basis of our results, it can be stated that in potato production variety should be chosen in accordance with the aim of production and technology should be adapted to that specific variety. -
The effect of keeping technology on the microbiological status of raw milk
67-75Views:512The importance of the quality of raw milk increased after Hungary had joined to the EU. On delivery of raw milk, the microbiological quality, especially total plate count of the milk is very important. Twenty-two farms (7 large, 4 medium-sized, and 11 small farms) were included in the study. We considered the different farm size, keeping- and milking circumstances during the selection of farms. The examined large farms use loose housing system (cubicle, deep litter) and milking parlour. Most of them use preand post-milking disinfection. In the medium-sized farms, loose,
deep litter and tie-stall housing system, as well as milking parlour, pipeline milking and bucket milking occurred. All of them use preand post-milking disinfection. Small farms use tie-stall housing system, bucket milking and udder preparation by water. Unfortunately, they do not use pre- or post-milking disinfection. In the large and medium-sized farms mainly Holstein Friesian, in the small farms Hungarian Simmental breeds can be found.
The aim of our research was to examine the microbiological status of the raw milk produced in dairy farms (total plate count, coliform count, Escherichia coli count, Staphylococcus aureus count, psychrotroph bacteria count, furthermore yeast and mold count); sources of the contamination; connection between the microbiological quality of produced milk and housing-, milking technologies of farms; furthermore the hygienic circumstances of milking and milk handling of the farms, by the examination of coliform bacteria and Escherichia coli contamination.
During the examination of the connection between the different farm sizes, various housing- and milking forms and the microbiological characteristics we observed similar tendencies in the case of total plate count, coliform count, yeast and molds count, furthermore psychrotroph bacteria count. The value of these parameters was significantly higher in small farms, and infarms which use tie-stall housing forms, bucket milking, udder preparation with water, and which do not use pre- and post-milking disinfection.
The results showed that besides cooling, the milking procedure and the type of udder preparation had the largest effect on the total plate count. Statistical analysis shows that in medium and small farms the combination of pipeline milking – tie stall housing system – disinfectant preparation of the udder; in large farms the combination of milking parlour – loose cubicle housing system – dry preparation of the udder are the most appropriate in the aspect of the total plate count. We experienced that in farms where the hygienic instructions are not followed – and therefore
equipment used during the milking and handling of milk is very contaminated – or rather the separation of mastitic cows’ milk is not appropriate, different microorganisms may contaminate the produced milk. -
Opportunities of utilization of real-time ultrasound technique in beef cattle breeding
45-52Views:364The goal of the authors was to evaluate the repeatability and accuracy of real-time ultrasound technique under Hungarian conditions. Ribeye area was measured at first time on live animals, before the day of slaughtering with Falco 100 ultrasound equipment in Charolais fattening bulls. Ultrasound pictures were traced at two times by the same operator. After slaughtering, ribeye area (REA) was measured on the carcass by planimeter at the same anatomical point like ultrasound measurements. Statistical analysis was carried out to examine the relationship between carcass and ultrasound REA. After it, repeatabilty was established by comparing the ultrasound pictures twice.
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New challenges the establishment of district governmental offices and the regional public transport organising in Hajdú-Bihar county
87-91Views:233The re-establishment of historical district government offices in the Hungarian public administration system will ensure the availability of the provided public services on an integrated, citizen-friendly level. Reorganising of district borders and changing the district centres as well the settlement new administration services in the central cities will predictable restructure the citizens public transport attitudes. This study deals with the motivation, quantity and direction of the possible modifications on the public transport demand in Hajdú-Bihar County. The study goals to present the possible public transport organising interventions, and to find a balance between the changing demand and the regulation provided public transport instruments.
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Viticulture of Hungary
175-182Views:573For several thousand years, vine has been grown in the Carpathian basin, where the climatic and soil conditions are favourable for viticulture. During this long period, vine growing has been developing until it reached its current niveau. We grow propagation material, table grape and wine grape. The produced wine grape varieties are grown on the largest area, of which 72% is white wine and 25% is red wine. Only 3% remains for table grapes. The surface of vineyards is about 63 000 ha, which can be found in 22 wine regions. The biodiversity of vine is very rich in our country. There are a lot of native and valuable bred varieties and clones in cultivation. The resistant and winter frost resistant vine varieties have an important role in our continental climate. The in 75% of the vineyards is on hills and mountains, 25% of them is on the Great Hungarian Plain. High cordon with cane pruning dominates the training and pruning system.
Unfortunately, vine stocks suffer from a lot of diseases and by using pesticides we pollute the nature. Viticulturists in Hungary produce excellent raw material and provide oenologists with them who make wine of excellent quality.
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Early evaluation of use of fermented chicken manure products in practice of apple nutrient management
195-198Views:646According to the Green Deal efforts, the importance and relevance of organic fertilization will increase in the near future. Therefore, the investigation of the effects of different organic fertilizers on soil productivity and nutrient supply is a priority area of agricultural research. Organic fertilizer experiment was conducted in an eight-year-old apple (Malus domestica Borkh.) orchard at Debrecen-Pallag. In the trial Pinova cultivar was used. In this study, two different fermented chicken manure products were added to the soil (in 20 cm depth) to test their effects on soil nutrient status, plant uptake and fruit quality. It was found that the applied treatments slightly increased the pH and nutrient levels in almost all cases, but significant effect was not observed in all treatments compared to the control. Leaf nutrient contents (N, P, K, Ca and Mg) were measured in the experiment. Leaf nutrient status was not affected by the fermented chicken manure treatments. However, used treatments had strong effects on the fruit characteristics and inner parameters, such as fruit diameter and Brix value. Moreover, it was established that the applied organic fertilizers increased the yield significantly.
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Application of environmental accounting tools for agricultural companies
60-68Views:246Today there is an ever stronger requirement for companies to consider the environmental aspects of their operation. The incorporation of these aspects into the economic practise of agricultural firms in our country is still in its infancy and, moreover, it usually follows from outside coercion (legal regulation) rather than voluntary behaviour.
Consequently, in the Hungarian agrar-economics – contrary to the example of Western Europe – the application of environmental accounting in agriculture is a barely researched subject; this has been so even though the environmental policy of companies can be made more conscious by adding an environmental dimension to the organizational information systems.
The aim of our investigation is two-fold. The first goal is to form a method that quantifies the environmental load of companies, is capable of comparing environmental performance of companies with different sizes, and takes into account the specific attributes of agriculture as well. The second is to apply this method in practice, to prove that estimating the environmental load of companies is possible by processing already available data (fiscal, accounting and statistical) using new concepts.
In this publication we present the joint application of three methods – each belonging to the toolset of environmental accounting – for two companies dealing with both crop and animal farming in the Pannonian region. The three methods are partly built upon each other and partly complementary. The company-level environmental balance is capable to show the relations between a given firm and its surrounding, but realistic comparison between environmental performance of different companies or periods is only possible by using specific index quantities. -
The Dg RES generation, storage, utilization and integration program ’1 village – 1 MW’ of the Bükk-Miskolc Region, Phase 1–3.
233-235Views:203The 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.
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Need for measurement of the innovation at Hungarian SMEs
5-13Views:263Competitiveness studies have shown that innovation could be breakout point for some economies, regions and enterprises. Knowledge acquisition, creation and exploitation of the knowledge base have been an essential element for economic growth. These knowledge-based economic processes come together with the innovation. Measurement of innovation by indicators has been playing a really emphatic role in making strategy whether it is national or EU planning.
Enterprises have always tried to measure and quantify their innovation activities mostly through the results of their economic process. Companies have generally considered their products as part of the innovation. That was the reason that in most cases they only and exclusively focused on the finished product. Some of them was able to realize that details of the production process must be taken into account in order to the whole innovation activity could be measured.
That is why I find it important to examine of what the innovativity of enterprises is made of, and in which way they can be measured.
In addition I was looking for the answer to the questions that how much the measuring method allows you to compare enterprises for further examination.The development of measurement methods is an essential moment of the article. As it is compiled for me the most important aspect of innovation, according to the statistical document, the Oslo manual guides you through the measurement methods and operational processes They play a very important role in proving my hypothesis. Overall, our country’s innovation results show those areas where we have high endowments, and also those where are the weaknesses.
Of course, systems and tools defined by the governing authorities of national economies will have the main role but the activity of the European Union will be the frame in the end, because without subsidies from the EU budget, national budget wouldn’t be enough to implement these aims.
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Effect of facility location on haulage efficiency
204-209Views:160In the 21st century, every economic sector must use the chances of evolution, technical and technological acquisitions, due to the level of competitiveness on the market. Such a sector as agriculture, where technology and the ideology of production are changing and adapting very slow to global expectations, by taking maximum advantage of opportunities, is a more central question. The greatest problems of Hungarian agriculture’s competitiveness are that this sector is very weak in capital and production costs make producers uncompetitive on the market. We can remedy this situation by using sources logically, purposefully and system approached. Logistics can provide the most useful assistance in such efforts.
In agricultural logistics, there is a great deal of uncovered territory. The aim is to transplant methods that are working correctly in other sectors into the agricultural sector, while maintaining development. One of the most important areas is transport logistics and material movement. Methods of analyzing and planning transportation and material movement found in professional literature do not take into account the specific needs of agricultural production. My aim is to examine the effect of facility location in the running of an enterprise. Through the results, I make suggestions for modifying the currently used logistic method and suggest further methods of examination. The effect of agro-specific needs must be examined in carrying out innovations and making logistical planning methods reliable. -
The relationship between silver crucian carp (Carassius auratus gibelio bloch) and fish poulations of natural waters
30-36Views:359The fisheries management on inland waters is very complicated. Often the unclear propriety rights make the normal management difficult, and other times the stocking of the waters is problematic. In the last hundred years a lot of new fish species have been introduced to Hungary. Lot of them have found their place in the Hungarian fishfauna, till others have caused big problems for the fish farmers, and the anglers too. The biggest problem was caused by the topmouth gudgeon (Pseudorasbora parva Schlegel, 1842) brown bullhead (Ictalurus nebulosus LeSueur, 1819) and the silver crucian carp (Carassius auratus gibelio Bloch, 1782). In this article I show what kind of problems were caused by the silver crucian carp, because it seems that this fish is the most harmful.The damage caused by silver crucian carpposesa complex question. To get into the ponds and rivers, the crucian carps occupy the territory form the native fishspeciesandthesilvercrucian carp competes with these fishes for food, too.The silver crucian carphasa special reproduction method and because of this the speciesis expand rapidly. The silver crucian carp is able to reproduce with other cyprinids, and because the female silver crucian carps are triploids every fingerlings will be silver crucian carp.This fish is a vectorfora lot of diseases, which can easily spread over for other species.
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Effect of vitamin e and selenium supplementation on the antioxidant content of milk and dairy products in dairy cows
9-12Views:391In 2007, the aim of the Ányos Jedlik program and the call for tenders was to support application-oriented, strategic research and development projects, which can increase the competitiveness of the Hungarian economy. In the framework of our project, we intended to examine whether non-protected antioxidants - in this case: vitamin E and selenium – used as feed-additives can increase the antioxidant content of milk. The milk with an increased level of vitamin E and selenium content can be used for producing functional foods which will represent competitive products on the current market of milk products. Our results show that the use of vitamin E and selenium as feedadditives can significantly increase the amount of vitamin E and selenium in the milk and also in the diary products.
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Correlations of the global, regional and local factors of the anthropogenic effects on the water reserves of the Earth’s crust
85-92Views:221The decrease in Earth's drinking water resources and the degradation of its quality has become a critical problem. Our planet's total water supply is estimated to be around 2 billion km3s. This is only 1% of Earth's own weight. Of this small amount only a tiny 3% is fresh water, of which 79% is forzen in glaciers and 1% is present as surface waters.The ratio of water stored in soil is around 20%. This is 0.2% of the total water supply. Our study aims to summarize the layered groundwater aquifer systems and its changes which are the results of anthropogenic effects in both global and hungarian respects and also for the region of Debrecen.In particular with regard to the geological and ecological level where irreversible
processes take place. All this is discussed in the context of cause and effect. Pointing out the dangers of excessive deep groundwater extraction and the contamination caused by toxic substances that are the byproducts of modern life. In addition we discuss the Water Directive of the European Union which gives a policy for community action concerning the goal to achive the status of „in good condition” for our waters till 2015. -
Preliminary data on the effect of semi-synthetic baits for Noctuidae (Lepidoptera) on the non-target Lepidoptera species
71-80Views:546Noctuidae are one of the most important Lepidoptera groups containing dangerous pest species. Monitoring and detection of these pest species is routinely performed by traps baited with sex-pheromones. Baits that attract both males and females were developed for improved pest management. First the effectiveness of different synthetic compounds was evaluated. We also tested semi-synthetic baits that contained both synthetic and natural components (wine and beer). These were more attractive for moths considering species richness and abundance. Disadvantage of this increased effectiveness is that the traps catch more non target, rare and even protected species. In this study we analysed the effect of semi-synthetic baits developed for Noctuid moths containing wine on other non-target Lepidopterans. In the six sampling sites traps caught 17158 individuals of 183 Lepidoptera species. The number of Noctuidae species was 124, while their proportion was 84.4%. The traps caught 813 individuals of 9 protected and 20 valuable species, which was only 4.7% of all Lepidopterans. In contrast the mean proportion of 33 dangerous and potential pest species was 31.3% (5375 individuals). Number and abundance of both protected and pest species were affected by landscape structure. The risks of catching non-target species was higher in species rich natural and semi-natural landscape. In homogenous arable lands the number and proportion of valuable Lepidopterans was not significant.
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Upgrading breeding value estimation in beef cattle
451-458Views:371This paper gives a summary of the possibility for applying genomic information for breeding value estimation in beef cattle breeding. This process is called genomic prediction and is now widely used in dairy cattle globally as well as in some beef and sheep populations. The advantage of genomic prediction is a more accurate estimate of the genetic merit of an individual at a young age thereby facilitating greater annual genetic gain, predominantly through shorter generation intervals. Genomic predictions are more advantageous for sex-linked (e.g., milk yield), low heritability (e.g., fertility) and difficult-to-measure (e.g., feed intake) traits. The larger the reference population, on average, the more accurate the genomic predictions; additionally, the closer genetically the reference population is to the candidate population, the greater the accuracy of genomic predictions. Research is continuing on strategies to generate accurate genomic predictions using a reference population consisting of multiple breeds (and crossbred). Retrospective analysis of real-life data where genomic predictions have been operation for several years clearly shows a benefit of this technology.
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Distribution of the American grapevine leafhopper (Scaphoideus titanus Ball 1932) in surroundings of Nagyvárad (Oradea, West Romania) and Debrecen (East Hungary)
39-44Views:427The first European appearance of american grapevine leafhopper (Scaphoideus titanus), which is the vector of Grapevine Flavescence Dorée phytoplasma (‘Ca. Phytoplasma vitis’), were detected in France in 1924. The leafhopper has been distributed since 2006 in Hungary and now it occurs in the whole country, while the first record of the phytoplasma was published in 2013.
We studied the distribution of the leafhopper in surroundings of Nagyvárad (Oradea, West Romania) in 2015 and surroundings of Debrecen (East Hungary) in 2016. During the studies 17 sites were sampled. The leafhoppers were found in six Romanian places with relatively low abundances while it occurs in all studied Hungarian sites and two of them showed extremely high frequenncy. -
The use of Common duckweed (Lemna minor) as a biological filter in the rearing of hybrid African catfish (Clarias gariepinus x Heterobranchus longifilis)
107-112Views:612The African catfish (Clarias gariepinus x Heterobranchus longifilis) is one of the most important fish species in Hungarian aquaculture. The larvae and juveniles are reared at high feeding rates, which can reach up to 10% of the biomass. Intensive feeding results in large amounts of effluent water, directly proportional to the intensity of fish production. The aim of this experiment was to investigate the potential of Common duckweed (Lemna minor) as a biological filter and its nutrient removal capacity during intensive fry rearing of the hybrid African catfish. In a recent study, two experimental recirculation systems, identical in water volume and design, were set up, in one of which duckweed was grown under aquaponic conditions, where the concentrations of nitrogen and phosphorus forms were monitored and the production parameters of the fish were determined. The results obtained from the experiment showed that the use of duckweed as a biological filter improves the water quality of the recirculation system. A significant amount of plant biomass was produced, which mainly reduced the nitrate and orthophosphate concentrations in the system water. As a consequence, the survival of hybrid catfish was improved, which also affected biomass growth, but had no effect on other parameters.