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Survival Analysis of Hungarian Large White, Duroc and Pietrain Sows
31-36Views:453The aim of the present study was to perform lifetime performance analysis in three pig breeds; Hungarian Large White (n=295), Duroc (n=76) and Pietrain (n=91) on a commercial farm using analysis of survival sows. We took into consideration the age of sows at the time of their inclusion into breeding, their age at the time of culling, time spent in production, number of mating and parities, parity percentage, intervals between litters, number and mean of piglets born alive and born dead, number of raised piglet litters, number and mean of 21 days old piglets, the weight and mean of raised litter and raise percentage.
We carried out the analysis by SPSS 22.0. Single factor analysis of variants, Kaplan-Meier analysis and Cox PH model were used. The determination of the significance of risk rates differences was done by Wald chi square test.
Our results showed that the average culling age were 1056 (±33.52) days for the Hungarian Large White, 735 (±73.56) days for Duroc and 818 (±71.98) days for the Pietrain.
The log rank test of the survival analysis indicated a significant difference between the three tested genotypes (χ2=16.981, P<0.001), which means that the survival percentage of the individual breeds varied significantly from one another. In comparison with the Hungarian Large White genotype the Duroc genotype has a 1.6 times higher (P<0.001) culling risk while that of the genotype Pietrain was 1.36 times higher (P<0.001).
Our results can be used to compare the breeds kept under the same conditions and to compare the life span of one genotype under different farming conditions. Factors that increase survival and improve the profitability of pig farming can be determined by this method.
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Examination of the interval between litters (IBL) of different genotype HLW sows using survival analysis
13-17Views:452In this study our aim was to find out if there is a difference between the genotypes determined for the previously identified mutations of seven genes of the Hungarian Large White in terms of the time spent in production. We identified the previously determined alleles of the seven genes (BF, EGF, ESR, FSHβ, H2AFZ, LEP, PRLR) related to proliferation that were and performed the survival analysis between breeds indicating the risk of culling and the time spent in production on the given farm. Based on the results of survival analysis by Log-rank test, Breslow (Generalized Wilcoxon) and Tarone-Ware test we concluded that they indicated a significant difference in case of the genes BF (Breslow and Tarone-Ware tests) the EGF (Log-rank and Tarone-Ware tests) and ESR (Log rank test) based on which the curves of the survival of the certain genes varied form one another significantly.
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Effect of different weaning time on the growth and survival ofCommon carp (Cyprinus carpio L.) larvae
55-59Views:738Within our experiment, we studied the combined effect of live food application and feed training on the production parameters of carp larvae. In addition, we examined whether there is a difference in the growth rate and survival rate of the specimens of Szeged mirror landrace reared in similar stocking density but with different treatments.
Specimens of Szeged mirror landrace from induced propagation were placed into 12 pieces of 40-liter aquaria. For the 4 different treatments, (K, A3, A6, A9), live food (Artemia salina) was fed, as well as feed training was applied.
We also sought to find an answer as to how our feeding and rearing conditions can affect the production parameters of common carp fries and what impact these conditions may have on their survival rates. At the end of the 2-week experiment we determined the individual weight gain of the carp fries, their survival rate and the biomass growth. The purpose of the study is to examine the optimum timing of shifting from live food to feed for carp larvae.
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Effect of floor type and bedding system on sows lifespan
155-160Views:271The paper studies two nucleus pig farms in the Great Plain region of Hungary which have same management, same feeding system but different breeding technology (Farm A had solid floor with straw and Farm B had slatted floor without straw). The genetics of sows were crossbred Dutch Large White and Dutch Landrace. The comparative examination was based on the causes of culling according to the different floor type. To the analysis of culling reasons was applied the methods of survival analysis.
In the analysis there were used the Kaplan-Meier method and the Cox Proportional Hazard model to the estimate the difference between the farms. The results of survival analysis showed significant difference (p<0.05) between the lifespan of sows that caused the difference between the survival probabilities of sows culled due to lameness. Furthermore there was showed that the sows kept on solid floor with straw have stayed in production longer than on slatted floor without straw. The hazard ratio was 1.434 that means that the culling due to lameness is 1.434 times higher by the slatted floor without straw facing by solid floor with straw.
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Comparison of growth parameters of 40 varieties/clones short rotation coppice willow (Salix)
99-104Views:211The plantation of willow varieties was established in 2009. The 40 different varieties and clones of Salix were planted at a research field in Kolíňany (Nitra district). The paper evaluates results from the first growing season in 2009. The survival rate of planted cuttings ranged from 55.56 % to 100.00 % after the first year. The lowest survival rate was reached by Terra Nova variety. The stem numbers per plant ranged from 1.17 ±0.37 to 2.53 ±0.98. The average height of one-year old stem varied from 65.82 ±36.60 cm to 225.58 ±68.61 cm. The average stem diameter ranged from 6.90 ±2.63 mm to 14.34 ±3.39 mm. There were statistically very significant differences in parameters of stem height stem diameter and stem numbers per plant among studied varieties/clones. The statistic method used was analysis of variance ANOVA. The varieties were then divided into 6 groups according to their similarity in observed parameters after the first growing season by cluster analysis. The best results were reached by varieties/clones classified in the second group. The survival rate, stem diameter and stem height values of these varieties/clones were above average.
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Economic policy strategy of UNITAB
83-90Views:147Under the leadership of the International Association of Tobacco Producers – UNITAB – there is a struggle going on for stabilizing the situation of European tobacco growers. UNITAB unites the tobacco associations and tobacco growers of all EU countries.
Tobacco production ensures economic stability for more than 100 thousand small- and medium-sized farms in the rural areas of 10 EU countries. In addition, its social importance in the survival of rural communities is emphasized by the 400 thousand direct or related seasonal jobs.
Within the framework of the CAP reform, the European Union is gradually changing the regulations of production. This is based on the decoupling of subsidies, which will be implemented in two phases. Between 2006 and 2009. the decoupling will be 40% and then after 2010, 50% (the other 50% will be used for restructuring within the second pillar). The question is raised, how will the second 50% be restructured to the second pillar. Between regions and how it can be ensured that this support would go to tobacco production.
With its participation in the principles of the European Tobacco Charta, UNITAB targets for production under economically-balanced conditions, the production of products meeting the customer requirements, consideration of the working conditions (especially for seasonal workers) and adherence to the health regulations related to the consumption of the end product already in the production and environmental protection. They aim to ensure the survival of the sector via tobacco growing with sustainable development and high quality. To maintain the continuity, there is a need for the support of regional, national and EU authorities. Future of the sector is dependent upon adaptation of tobacco growers and upon meeting the social expectations.
According to UNITAB, efforts should be made to modify the decisions so that the majority of the funding could be used by the grower. The tobacco industry has been able to effectively fight for its survival. -
Examining the production parameters of European perch (Perca fluviatilis) juveniles under different lighting conditions
149-153Views:350European perch (Perca fluviatilis) is a native predatory fish in Hungary, and a promising new species of fresh water aquaculture nowadays. The European perch can be characterized by a high stress sensitivity during the intensive rearing, thus the optimization of environmental conditions has significant importance in the early life stages of fish. The aim of our study was to determine whether the light intensity and darkening of the water by humic acid affect the survival and growth performance of European perch juveniles. The experiment lasted for 28 days. Rectangular aquariums were arranged in 3 lines, the test environment consisted of 24 units. The experiment was set up with 10–10 fish per aquarium, total of 240 individuals. The average wet body weight of the fish at the start of the experiment was 1.69 grams. During the experiment, 6 treatments in 4 replicates were set up. In the first row, we set up 305.6±66.0 LUX (L), in the second row 118.0±24.4 LUX (C), and in the third row (D) 17.0±8.6 LUX illumination was set up. In each row the water of four aquariums were darkened by the addition of humic acid (H) (L, LH, C, CH, D, and DH). At the end of the experiment high survival rate was observed in all treatments. Examining the survival rate, the best results were found in the strongly illuminated treatments (L; LH- SR%=100±0.00). The observed mortality was caused by cannibalism. Regarding the individual body weight, the best results were shown by the treatments where the aquariums were illuminated with lower light intensity (C: 4.66±0.33 grams) and the aquarium water was darkened by humic acid (CH: 4.93±0.15 grams). The results of the C and CH groups were significantly better compared to the other treatments, however, they did not differ statistically from each other. The darkening of the water had a positive effect on the individual body weight of fish reared under full light (L: 3.73±0.28 grams; LH: 4.33±0.28 grams), whereas in the case of fish reared in the lowest illumination, the addition of humic acid did not affect the results (D: 3.78±0.15 grams; DH: 3.80±0.26 grams). In case of SGR (C: 3.64%/day and CH: 3.74%/day) and FCR (C: 0.84 g/g and CH: 0.78g/g) the best results were obtained by the C and CH treatments, also.
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Cannibalism and its importance in Aquaculture: A review
43-54Views:630Intracohort cannibalism may lead to significant losses during the early life stages of farmed fish. The mechanisms driving cannibalism dynamics are common across many fish species and are closely linked to the factors that influence growth variation within a population. This genetically encoded behaviour allows the individual to eliminate competitors in the competition for resources and increases the chances of survival and reproduction. Many fish species display aggression towards individuals of the same species, which can often lead to cannibalistic behavior. This foraging strategy is also present in intensive aquaculture systems, and its economical, ecological and phylogenetic implications have been debated by many researchers. Many fish species can be produced economically in recirculation aquaculture (RAS) systems, but the efficiency of larval and juvenile rearing remains a bottleneck for most species. The success of initial rearing depends on many factors. In addition to genetic factors, the level of cannibalism is mainly influenced by the applied production and feeding technology. Literature suggests that mortality during larval rearing can be as high as 50%, largely due to aggression. In the case of predatory fish species, the presence or absence of certain husbandry conditions can lead to even higher levels of cannibalism, which significantly reduces production yields by causing mortality and secondary injuries, thus further decreasing the survival rate. This review therefore aims to identify and quantify the effects of biotic and abiotic factors that influence cannibalism.
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Survival analysis of sow longevity and lifetime reproductive performance – Review
75-80Views:545Sow longevity plays an important role in economically efficient piglet production. Improving sow longevity results increase in the productivity and profitability of a sow herd. Longevity is a complex trait with many factors that can contribute to a sow having a long and productive life. Not only the sow’s genetics, but also nutrition, environment and the management policies are important. In addition, the removal of non-productive sows along with the introduction of replacement gilts is an essential part of maintaining herd productivity at a constantly high level. The objective of this paper was to summarize the current knowledge about the sow longevity and lifetime performance values, as well as, discusses the survival analysis methods for sow longevity traits. This method can estimate the hazard rate indicating proportional risk of sows being culled at any given time, in addition, it is able to investigate the effects of different factors on longevity. Identifying factors that influence the longevity could assist many commercial pig producers in becoming more efficient.
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Analysis of the Station Test Results of the Hungarian Large White and Hungarian Landrace Populations Applying Survival Analysis
37-40Views:165Authors analysed the days of fattening in relation to the station test for Hungarian Large White and Hungarian Landrace pig populations using, survival analysis. Survival and hazard functions were calculated in both groups separately for castrates and females. The log-rank test was applied to determine the significance of the differences across the groups. Authors established that within the breeds the functions of the castrates and females were significantly different, namely the castrates reached final weight sooner or, in cases where final weight was not reached by a certain period, castrates reached this weight during the next time unit with a higher probability than the females.
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Preliminary results of intraspecific sterlet hybrid (Siberian sterlet × sterlet) rearing under intensive conditions
17-19Views:208Due to early maturation and a small size, sterlet (Acipenserrut-henus) is a very advantageous fish for intensive sturgeon farming with regard to caviar production. According to our previous observations, the growth potential of Siberian sterlet (A.ruthenusmarsiglii) is higher than that of the European one. In our experiment, sterlet and an intraspecific hybrid (Siberian sterlet × sterlet) were tested under intensive tank conditions. During the 8 weeks of the experiment, survival, growth and size heterogeneity were investigated. According to the results, there were no significant differences in survival and growth but the size heterogeneity was higher in the hybrid. It is supposed that, in our trial, the applied water temperature range (24.0–25.5 °C) was optimal for sterlet, but was probably above the optimal range for the hybrid.
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Use of essential trace elements enriched Artemia in the larval rearing of barramundi (Lates calcarifer)
11-16Views:343Artemia is a vital nutriment in the rearing of barramundi (Lates carcarifer), however it’s mineral trace element content does not cover the requirements of the larvae. In our experiment the assumption was wether the cobalt, zinc and manganese concentration of Artemia could be increased during a 24 hours of enrichment period, as well as we wanted to investigate the resulted interactions between the elements. For this purpose 50, 100 and 1000 mg l-1 cobalt-chloride treatements (Co50, Co100, Co1000) were applied while in the case of 50 and 100 mg l-1 treatments the enrichment was also complemented with zink-sulphate and manganese-chloride in the same concentrations. According to the results the zooplankton were able to accumulate cobalt in higher amount, and yet zinc and manganese had no significant effect on each other, a strong synergistic effect occurred between cobalt and manganese. After the enrichment period the impact of essential trace element supplemented live feed on the survival and growth of barramundi larvae was also studied. The experiment was carried out by using 15 days-old larvae applying a total of 9 treatments for two weeks (Control, Co50, Co100, Mn50, Mn100, CoZn50, CoZn100, CoMn50, CoMn100), in duplicates. Considering the per cent of survivals, no significant difference was observed between the treatements (P>0.05). In the case of CoMn50 and CoMn100, the loss statistically increased (P<0.05) compared to the Control (80.5±4.95%) group. Our results show, that the Mn100 and CoMn100 treatements resulted in ignificantly higher (P<0.05 ) in divid ual bod y w eight s, how ever taki ng the survival also into consideration the Mn100 treatements proved to be the most
effective. -
Production of novel fermented milks
303-305Views:259The objective of this research was to test the influence of various natural substances on acid production, growth, and viability of characteristic microorganisms in yogurt and probiotic fermented dairy foods. Oligofructose, inulin, honey, and the dried biomass of Spirulina (Arthrospira) platensis were found to stimulate the growth rate and acid production activity of the major thermophilic diary cultures tested and, in addition to this, the presence of the aforementioned substrates also improved the survival of starter bacteria in fermented milk products during storage. The reduced production time of cultured milks resulted in increased production efficiency. The stimulatory and/or protective effect of oligofructose,
inulin, honey, and Spirulina on Bifidobacterium spp. is probably the most important finding of this study because bifidobacteria do not grow well in milk and they have low survival rates in conventional fermented milks. Some of the bioactive substances tested were also capable of exerting an antifungal effect on spoilage yeasts and molds, and improving the nutritional and sensory properties of the final product, thus providing a new opportunity for manufacture of functional fermented dairy foods. -
Does the feeding frequency influence the growth performance of European perch juveniles (Perca fluviatilis) during intensive rearing?
123-128Views:310The European perch (Perca fluviatilis) is a predatory fish species. Its aquaculture production is increasing worldwide. Feeding and the frequency of feeding are important elements of intensive fish rearing. The aim of our experiment was to examine the optimal distribution of the amount of feed, at the same feed rations. The experiment lasted 42 days. Three treatments were applied in 4–4 replications. The first treatment was feeding twice per day (T2), the second treatment was feeding three times a day (T3), and the third group was fed four times a day (T4). 10 European perch juveniles were stocked per tank, with an individual mean body weight of 3.93 ± 0.06 g at the start of the experiment. The survival rate (S%) was above 90% for all treatments. The T2 treatments produced the most favourable harvest weight (13.96 ± 0.14 g) and specific growth rate (SGR = 3.08 ± 0.01% day-1), but no significant differences were observed between groups. In terms of feed conversion ratio, the best result was obtained by (T3) (FCR =1.06 ± 0.18 g g-1), but no significant difference was found for this indicator neither. The results of the trial indicate that the feeding frequency does not influence the production parameters.
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The use of essential trace elements in the juvenile rearing of barramundi (Lates calcarifer
33-38Views:367Barramundi (Lates calcarifer L.) is a predatory fish species native in Southeast Asia and Australia. Based on the geothermal potentiality of Hungary the warm-water fish can be reared successfully. Zooplankton in the wild contains minerals in a higher concentration than the usually fed newly hatched Artemia nauplii, therefore essential trace elements, such as cobalt, zinc and manganese play an important role in the larviculture of barramundi. Cobalt is vital in trace amount for many living functions of vertebrates, however, lower number of papers are available considering the nutritional aspects. Nevertheless. improved growth performance was observed in cases of some fish species when diet was supplemented with CoCl2. Zinc and manganese are also vital for optimal growth and accordingly are investigated and applied diet supplements in aquaculture.
The main aim of the recent study is to investigate the effects of cobalt, manganese and zinc on the growth performance and homogeneity of fish when a commercially available dry diet is supplemented with trace elements individually and in combined treatments. A total of 6 treatments were set in a randomized blocked design where the concentrations of the applied elements were 50 mg kg-1 for CoCl2, for ZnSO4 and for MnCl2 individually, as well as for CoCl2 along with ZnSO4 and for CoCl2 along with MnCl2 in combination. Although the production parameters of larval barramundi were positively affected by the addition of trace elements when the retention of minerals occurred through nourishment living organisms, statistically no differences were found between the treatments considering the growth performance of barramundi juveniles either when dry feed was supplemented with cobalt, manganese or zinc (p>0.05). While the use of cobalt and manganese in combined treatments produced a less uniform larvae in size and as a consequence of increased heterogeneity, survival was significantly reduced by the cannibalism, the sizes distribution of barramundi juveniles wasn’t affected by the dry diet supplementation of these elements.
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Examination of the efficacy of different fungicides against Macrophomina phaseolina and Sclerotinia sclerotiorum in laboratory conditions
21-24Views:471Macrophomina phaseolina and Sclerotinia sclerotiorum are two significant fungal pathogens of sunflower. M. phaseolina causes charcoal rot and ashy stem blight in several important crop species. Sclerotinia sclerotiorum causes white mold disease which can occur as middle stalk rot, head rot and premature plant death. Due to the wide host range of the two pathogens and their survival structures, crop rotation cannot provide sufficient protection against them. In our experiment, we selected two fungicides, Mirage and Prosaro, which are widely used in practice, and we tested their efficacy against the two pathogens. The efficiency of these fungicides was tested at a concentration of 10; 20; 50; 100 and 500 ppm. The Prosaro totally inhibited the mycelial growth of both pathogens at a concentration of 50 ppm, 100 ppm and 500 ppm. The Mirage caused total mycelial growth inhibition in all treatments against both pathogens.
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Utilization of live feeds in fish larviculture: A review
103-116Views:23This review examines the significance of live feeds in commercial aquaculture industry for production of fish and shrimp larvae, along with various challenges and prospects. Live feeds are an essential food source in larviculture, especially for marine fish, which depend on them for nutrition during the initial days of exogenous feeding. They are palatable, highly digestible, and their movement stimulates natural hunting and foraging instincts, promoting better development, lowering captivity stress, and increasing survival rates. Artemia is the most commonly used live feed in larviculture; however, it has low levels of omega-3 HUFA. Copepods are the most nutritionally rich live feed, containing high levels of DHA and EPA. Despite these benefits, they are less frequently used in larviculture due to technical challenges associated with large-scale cultivation at high densities. The use of live feed is labour-intensive and costly. The feeding period for fish larvae can be shortened using a co-feeding strategy. Microalgae rich in DHA have been utilized to enrich live feeds. Further research is needed to determine the most effective approach to significantly reduce the weaning time of fish larvae from live feed. This will lead to gradual and eventual complete replacement of life feed in the near future.
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Present situation and future prospects for Hungarian fruit and vegetable sector
31-38Views:144Changes in people’s lifestyles and the emergence of nutritional science have created favorable opportunities for a boom in fruit and vegetable consumption, which have been fully exploited by the adaptive fruit producer and exporter countries. Unfortunately, Hungary is not one of these countries. Affected by a number of uncertainty factors, the Hungarian fruit and vegetable sector has fallen behind international trends, seeking opportunities for survival (Erdész, 2007).
The impacts of the country’s accession to the EU have been more adverse than expected. While no administrative measures are used to control production and the increasing competition and import have put Hungarian producers to a loosing position. The cooperation producers, the well-organized work of professionals and the coordinated activity of producers marketing organizations may resolved some of the problems affecting the sector.
The fruit and vegetable sector can also anticipate significant changes during the new seven-years budget period of the CAP reform.
With the new drat reform of the sector, the European Commission intends to simplify the common organization of the fruit and vegetable market, improve competitiveness, increase market orientation, promote fruit and vegetable consumption and to continue the environmental efforts.
Hungary has had great expectations concerning the reform of market regulation, but the Commission proposal didn’t bear out the expectations, because the new proposal includes insignificant changes in important issues and fails to provide sufficient additional resources for the catching up of he new member states. -
The effects of bioactive feed additives for the production parameters of common carp (Cyprinus carpio) fingerlings in intensive recirculating system
35-41Views:388For the appropriate quantity and quality of fish meat the pond farmers need to use up to date nutrition and feeding technologies. Recently the intensification of the carp production is stepping up with the availability the proper quality of the artificial feeds. The using of different feed additives make a better feed conservation ratio, faster growing rates and more uniform stocks.
In our experiment what is made with common carp (duration of the experiment was 8 weeks long) we compared two different kinds of feed additives in different doses. One of them contains only natural mineral elements and the other additive is a natural origin probiotics. Both additives were used in the quantity of 0.5, 1 and 2% of the total feed. By the result of the 8 weeks experiment it could be said, that the using of the humic acid based mineral elements feed additive. Makes a better FCR comparing with the control stock, but was not as good as the using of the probiotics. At the humic acid treatments the more doses, the better FCR value, but at the probiotics it wasn’t true. The 0.5% probiotic treatment gave the best result. It is concluded that the using of the probiotic feed additives always gave a better performance of the fishes (average weight, biomass, FCR) than the humic acid treatments. The using of the feed additives hasn’t got an influence for the survival rate of the carps.
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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:488The 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.
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The launch on the way to development or the „revival”... (Comparisons of theoretical and practical approaches apropos of the change and crisis management process of smes and mature companies) .
65-70Views:120Hungarian SMEs, just like those in other EU member states, often cease for various reasons. Among these factors are many, which should not necessarily turn out this way. These factors are studied in numerous countries while the attempt is also made to create the systems of conditions for these enterprises to recover – often through various aids and supports (from public supports to non-governmental initiatives). Among other things they are trying
to organize those services with the help of which – if there is the slightest hope for survival – those SMEs in trouble or having serious difficulties could avoid going down by recovering from
their problematic situation and getting improvements.
These days this issue comes up more and more urgently in Hungary, as well. It has quite a few signs indicating that – among other things – the reports, the enquiries and commissions of the
National Association of Change and Crisis Managers (VOE), all of which – just like "thermometers" – reflect this tendency well.
I have been doing research on this topic since 1993. As an expert I utilize them, and as a VOE member, vice president, then president I process the relevant Hungarian but mainly French
experience on the subject. I intend to present those few theoretical and practical results and applicable experience I have reached this way in this presentation of mine. -
Seasonal changes of photosynthetical parameters as a results of forest gap model
133-136Views:310Photosynthetic parameters of English oak (Quercus robur L.) as a member of Querco robori-Carpinetum were investigated in two different habitat in terms of gap forest management: in the gap and in the host forest. The artifical opening process of the forest resulted in more light for growing saplings and need for acclimatization. Photosynthesis is one of the most important way for plant life and plant production. In the centre of photosynthetic efficiency the quality and quantity traits of photosynthetic pigments are standing. During our work some photosynthetic parameters of plants (in the gap and in the forest as well) were measured: relative chlorophyll content as SPAD index, chlorophyll a and b content, total chlorophyll content and ratio of chlorophyll a and b. Based on our results no significant differences among our data in early spring. Although, during the summer significant differences occurred between the measured values in the gap and in the forest area. Lower total chlorophyll content was experienced in the gap, than in the forest area due to the lower chlorophyll-b content. Because of the high light intensity higher chla/chlb ratio was measured in the gap. The lower chlorophyll contents of gap habitat may have a part of the acclimatization process of photosynthetic apparatus against high light stress, which can determinate the survival chance of individual.
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Cytokinin and auxin levels in micropropagating Red Fuji and McIntosh apple varieties
53-59Views:176Effects of media hormone content on in vitro shoot multiplication and rooting were examined in cv. Red Fuji and McIntosh apple scions. Multiplication responses of shoots to different concentrations (0.5 and 1.0 mg/l) of 6-benzylaminopurine and 6-benzylaminopurine riboside were tested at two levels (0.1 and 0.3 mg/l) of indole-3-butyric acid. The best proliferation rate was achieved on medium containing 1.0 mg/l 6-benzylaminopurine and 0.1 mg/l indole-3-butyric acid in cv. Red Fuji (5.3) and on medium containing 1.0 mg/l 6-benzylaminopurine and 0.3 mg/l
indole-3-butyric acid in cv McIntosh (10.3). The length of shoots on these media was enough for rooting (38.4 mm in cv. Red Fuji and 39.3 mm in cv McIntosh). Shoots developed on the best proliferation medium were used for rooting. Effects of different concentrations of auxin in the root induction media and presence of activated charcoal in the root elongation media were examined on rooting capacity. The best rooting rate (100% in cv. McIntosh and 83% in cv. Red Fuji) was achieved when the root induction medium contained 1.0 mg/l indole-3-butyric acid. In general, rooting was inhibited in the presence of activated charcoal. Because of high in vitro multiplication and rooting rate and high percent of survival during acclimatisation, the methods described here make effective micropropagation processes possible for cv. Red Fuji and McIntosh. -
Overview of the evolutionary history and the role in citric acid production of alternative oxidase
83-88Views:244All organisms are exposed to countless environmental effects, which influence in a disadvantageous way their life processes. They continuously adapt to the changing conditions and respond to the stress impacts by defence mechanisms. Through different signal transduction pathways they are able to increase or decrease the expression of their genes and consequently modify their metabolic processes. My interest focuses on alternative oxidase (AOX) enzyme whose expression is often increased under biotic and abiotic stress. The so far proven and putative functions of the AOX play a role in the ability of organisms to adapt to different conditions, such as heavy metals accumulation, pathogenic infection, oxidative stress and lack of oxygen or nutrients.
AOX is a member of the di-iron carboxylate protein family. Members of the di-iron carboxylate protein family are present in all kingdoms of life. They are considered to have ancient origin. It is believed that their sulfide-resistant and oxygen-reducing ability played a role in the survival of organisms during the transition between the anaerobic and the aerobic world. It is assumed that the AOX arose in eukaryotes through a primary endosymbiotic event, and this event made possible the development of mitochondria. Afterwords, vertical inheritance, and secondary and tertiary endosimbiotic events led to its spread among eukaryotes. It is assumed that bacteria obtained AOX by horizontal gene transfer from plants.
AOX-catalyzed alternative respiration plays an important role in the operation of energy-producing and biosynthesizing system of microorganisms. In these cases, the regeneration of reduced cofactors is an essential condition, and therefore may be rate-limiting for biotechnological processes, including the citric acid production.
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The effect of different fat content fish feed on the production parameters and meat quality of the hybrid striped bass
33-37Views:444The interspecific ’hybrid striped bass’ is the result of cross breeding. Their offspring have got good chances of growth and tolerate extreme water temperatures and the content of dissolute oxygen more than their parents. Furthermore, they are more resistant to diseases. Therefore, the hybrid is perfectly suitable for intensive fishery production.
Our experiment lasted for seven weeks. We analysed the indices of growth and production of the hybrid as the consequence of nurturing them with two feeds of high nutritive value during this period. We examined the content of fat and of fatty acids in the flesh of these fish. There were no considerable differences in terms of weight gain, feed conversion ratio and uneven growth between the two groups, while survival was less likely among the the fish which had consumed more fat. We demonstrated, examining the flesh of the individuals which had consumed feed containing lower fat content, that it was fattier and contained more dry matter than those that had been fed of higher fat content. Besides, the content of omega-3 and omega-6 fatty acids was higher in the fish that had consumed less lipids.