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  • Preparatory studies for modelling production on protected grasslands
    64-69
    Views:
    145

    There is a mutual dependence between nature conservation activity and agriculture in Hungary, as the management of the protected areas cannot be achieved without ecological farming methods. Moreover, viable economic activity can be only imagined through the harmonization of agricultural and nature conservation interests. From a nature conservation point of view, grass management systems play the greatest role in domestic agricultural systems. Yet, due to the prohibition of certain management methods and the spatial and temporal restraints on grazing, nature conservation activities have priority on protected grasslands. While nature conservation activity is still of prominent importance, it is not equally suitable for the economical management of protected grasslands per se. With our examinations, we would like to emphasize the common interests of these mutually dependent activities and to promote bilateral cooperation. Our aim is to model the production of grass on the great pastureland of Hajdúbagos. Potential grass production levels are easily calculable with a computer model based on data collected through a series of test harvests, as well as by factoring in changing climatic factors and by simulating the effects of grazing animal species and stocks. This model is not only useful for determining the optimal number of the grazing animal stock and grazing method, and therefore the most suitable management strategy, but it also supports local farmers to be able to plan their activities. In this way, both nature conservation and economic aims can be easily harmonized, which would be an important factor for the sustainable development of rural areas.

  • Influence of 17-alpha methyl testosterone on the production parameters of common carp (Cyprinus carpio L.) fry
    37-43
    Views:
    220

    During our research we aimed at finding an answer as to what extent the different concentrations of 17-alpha methyl testosterone incorporated in the diet of common carp fries can influence the production parameters of the species, as well as how efficient their sexreversal can be with the use of this method. To this end, an aquarium experiment was conducted in the course of which four different hormone treatments were set and monitored. The fish feed was enriched with 17-alpha methyl testosterone in 50 ppm, 75 ppm, 100 ppm, 500 ppm dosages.

    The obtained figures revealed that the hormone treatments had no influence on the production parameters and conservation of the common carp fries. Further on, our team is to determine the sex of the fish through the examination of gonads during autopsy when they reach the 500 g average weight.

    Furthermore, a male specific test method which was supposed to be of great help in our attempt to select the sex-reversed specimens in the subsequent processes was also put to the trial. During the experiment the DNA-isolation of different sample types (muscle tissue, fin, mucus) of common carp with identified sex was successfully carried out. The extracted PCR product was examined with agarose gel. Our results indicated that the ccmf2 marker was applicable, however, the obtained figures were not reliable.

  • Effect of different weaning time on the growth and survival ofCommon carp (Cyprinus carpio L.) larvae
    55-59
    Views:
    273

    Within 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.

  • Recovery and confirmation of Haemonchus contortus from abomasal contents of roe deer (Capreolus capreolus) in Eastern-Hungary (Biharugra): A diagnostic case study
    59-62
    Views:
    105

    Gastrointestinal parasites are ubiquitous. They occur both in wild and domesticated animals. Among such parasites of veterinary importance is the trichostrongyle worms, out of which the Haemonchus contortus species is regarded as the most pathogenic one in the small ruminant industry. The occurrence of this parasite in the sheep flock is now very well documented and an established fact in Europe, although the parasite was original of the warmer climatic region. Studies on the cross-transmission of H. contortus between the wild and domesticated animals are also on the rise although the question of the direction of transmission is still debated. This is an important area that needs to be addressed as it could potentially contribute indirectly to mitigating anthelmintic resistance. Hungary also has reported its share of the occurrence of the parasite, mainly in the sheep flock and a certain population of roe deer. The study presented here is the preliminary results of a diagnostic case study that confirms the presence of H. contortus in wild ruminant deer species that are close to the domesticated sheep population.

  • Genetic diversity of the Hungarian draft horse assessed by mitochondrial DNA
    29-32
    Views:
    200

    Hungarian draft is a horse breed with a recent mixed ancestry. It was developed in the 1920s by crossing local mares with draught horses imported from France and Belgium. To genetically characterize the breed and to set up the basis for a conservation programme, we have employed a molecular marker: a 256-bp D-loop mitochondrial DNA fragment. We analyzed 124 horses representing Hungarian draft horses to assess the maternal phylogeography of the breed. Sequence analysis of a 256-bp segment revealed a total of 34 haplotypes with thirty-four polymorphic sites. High haplotype and nucleotide diversity values (Hd=0.953±0.001; π=0.024±0.001) were detected. The average number of pairwise differences were k=5.998. This breed counts 800 mares today, and only survive due to breeding programmes, this way each haplotype frequency depends on the extent to which mares are involved into the breeding. The reduced number of surviving maternal lineages emphasizes the importance of establishing a conservation plan for this endangered breed. Due to the revealed 34 polymorphic sites we could presuppose twelve maternal linages, which could be a first step for making a breeding programme.

  • Effects of bioactive plant extracts on immune-related gene expression of common carp (Cyprinus carpio)
    49-56
    Views:
    241

     In recent years, intensive fish farming has led to an outbreak of several diseases, and the health status of fish can affect the economy of aquaculture. Since fish health and intestinal health are in correlation, it may also have an impact on immunity. Accordingly, many natural feed additives are being used to improve immune functions. In our study, carotenoids, oligosaccharides, and anthocyanins were applied at 1 m/m% in feed to investigate their effects on cytokines, such as interleukin-1β (IL-1β), interleukin-8 (IL-8), tumor necrosis factor-α (TNF-α), and interferon regulatory factor-1 (IRF-1) in spleen and mid-intestine of 6 months old carp. Gene expression analysis was carried out to examine IL-1β, IL-8, TNF-α, and IRF-1 mRNA levels in fish spleen and mid-intestine. The gene expression level of pro-inflammatory IL-1β decreased in the mid-intestine of carotenoid-fed carp compared to anthocyanin supplemented group, but the effects of the bioactive plant extracts were not observed on the examined cytokines compared to control fish.

  • Effect of genotype on the hematological parameter of TETRA-SL and Hungarian Partridge coloured chickens at young age
    99-104
    Views:
    174

    Indigenous chickens are well known for their dual-purpose function and palatable meat. However, the information on their hematology parameters is lacking and hence hampering the poultry industry production of local breeds. The main objective of this study was to examine the hematological parameters of Hungarian Partridge Coloured hen (HPC) and TETRA-SL (TSL) genotype and determine the hematological reference interval values. This trial was part of the larger experiment where a total of 200 chicks (HPC + TSL) were reared. For this trial the blood samples were obtained from brachial wing veins of 8 chicks of each genotype for blood hematological analysis. The results indicated that some of the hematological parameters such as red blood cells-RBC, white blood cells-WBC, hemoglobin-Hb, hematocrit-Ht, platelets-Plt, lymphocytes-LYM, and granulocytes-GRAN were significantly affected by the genotypes (p < 0.05). The genotype did not affect the mean corpuscular volume-MCV, mean corpuscular hemoglobin-MCH, mean corpuscular hemoglobin concentration-MCHC, and GRAN (p > 0.05). The hematological reference interval values were slightly higher in the TSL genotype compared to HPC chicks. It is concluded that genotype has a significant effect on the hematological parameters. The results from this trial will be help and design the baseline reference values for the HPC genotype which will be useful in assessing the health status of these indigenous chickens.

  • Supplementary botanical examinations for modelling the grass production of the great pasture of Hajdúbagos
    17-21
    Views:
    59

    Our botanical survey at the great pasture of Hajdúbagos is a part of a broad research that aims to predict the production of the grass at the given area. As the mentioned pasture is a nature conservation area, the usage of artificial fertilizers or other classic grassland management methods in its handling are prohibited. Thus grazing is an important tool for the management of this area, however the not suitably regulated grazing order and the poorly calculated carrying capacity cause serious problems at some parts of the pasture. The prediction of the grass yield is essential to
    avoid both over- and both under-grazing and for determining the optimal number of the grazing animal stock and the grazing method, thus the most suitable management strategy.
    The potential grass yield is easily calculable with a computer model that will be established as a basis for determining the grass production. For the sake of getting an accurate view of the plant associations of the pasture, we created examination quadrates and determined all plant species found in the quadrates. After plant determination, we compiled a coenological table in which we marked besides the scientific name and families, the life forms of each species that refer to the structure, morphology and thus the adaptability of plants to their environment. We determined the
    TWR, so the thermoclimate, water and soil reaction values, the nature conservation values, as well as the covering values of each plant species (DB), and the total coverage of the examination quadrates (B%).
    According to the covering values, grasses proved to be characteristic plants at the examined pasture, thus we need to consider them influential in calculating the animal carrying capacity and with the rest of the information, we need to supply the model.
    The life forms and TWR indicators, all together with the nature conservation values provide further important data to the development of the management suggestion of the protected pasture. By examining these values to different parts of the area, we could get an exact view on the measure of the degradation effects. This promotes the determination of grazing methods and the forming of the boundaries of certain pasture sections, to avoid  those harmful anthropogenic effects that seriously endanger this extensive sandy pasture. 

  • The effect of β-glucan, carotenoids, oligosaccharides and anthocyanins on bacteria groups of excreta in broiler chickens
    15-20
    Views:
    168

    This study was conducted to examine the effect of natural compounds, such as β-glucan, carotenoids, oligosaccharides, and anthocyanins in the diet on bacteria gropus of excreta in Ross 308 broiler chickens. Chickens were fed 5 diets: control (basal) diet, a diet supplemented by β-glucan at 0.05%, and diets supplemented by carotenoids, oligosaccharides, or anthocyanins at 0.5% of each compound. On experimental day 19, excreta were collected to determine the proportion of Lactobacillus, Bifidobacterium, Campylobacter, Clostridium, and Escherichia coli. Samples were collected aseptically and snap-frozen in liquid nitrogen. Bacterial DNA was isolated from samples, then polymerase chain reaction using primer pairs designed to the 16S rDNA of bacterial groups were applied to define the proportion of the mentioned bacteria. Another universal primer pair was used to amplify a region of 16S rDNA of all the examined bacteria. Proportion of each bacterial groups was determined relatively to the intensity of universal PCR product band by gel documenting system and ImageLab software. Based on the results, carotenoids and anthocyanins increased the proportion of Bifidobacterium, which might imply the beneficial effects of the mentioned compounds on the bacteria composition of excreta.

  • Nest-site preference of Hooded Crow (Corvus cornix L.) in Debrecen, Hungary
    13-17
    Views:
    117

    In the past decade, the population of the Hooded Crow has shown significant growth in Debrecen, Hungary. The aim of this study was to become acquainted with the nest-site selection behavior of Hooded Crows in urban spaces. While our research revealed that the Hooded Crow is not particular when it comes to selecting among tree species for nesting, we did notice differences regarding nesting height. Hooded Crows living in the city build their nests higher up than those living outside Debrecen’s city limits. We also discovered a slight, insignificant difference between nesting heights and tree species, which is probably due to the different characteristics of the given tree species. As for nesting heights, we found that in typical urban habitats there were no relevant differences. However, when we compared these habitats in pairs, it came to light that nesting heights -when comparing solitary trees - wood segments and tree rows - wooded segments- did show significant differences, which can be explained by the various conditions provided by the habitats mentioned.
    In summary, the following results emerged from our research:
    1. The Hooded Crow prefers approximately the same nesting heights in all kinds of habitats, urban environment and tree species.
    2. The nesting height does not significantly depend on the habitat itself or on the tree species.

  • The effect of dissolved oxygen on common carp (Cyprinus carpio) and basil (Ocimum basilicum) in the aquaponics system
    89-96
    Views:
    254

    Aquaponics is an integrated system that combines fish farming (aquaculture) and hydroponic plant production. The objective of this study was to examine how the level of dissolved oxygen with or without an air pump affects water quality, fish output and plant growth parameters for common carp (Cyprinus carpio) and basil (Ocimum basilicum).

    Ebb – and flood aquaponics systems (with automatic syphon) was used. Two treatments were set in this experiment, one of which was the aquaponics system without air pump (unit I), where water of the plant bed was pumped two directions, one falling back to the fish tank oxygenating the water the other was pumped to the hydroponics unit. The other system (unit II) was designed with an air pump.

    In the course of the study, water quality parameters, such as oxygen saturation, dissolved oxygen (DO), electrical conductivity (EC) and nitrite were significantly different (p<0.05). Total basil biomass was higher in unit II. (5367.41 g). The final biomass of common carp were
    2829.45 g ± 79.24 and 2980.6 g ± 64.13 g in unit I and unit II respectively. Weight gain (WG) and specific growth rate (SGR) showed no significant differences (p>0.05) between the treatments. 

  • Reference genes for livestock gene expression profiling – Literature review
    81-89
    Views:
    144

    Quantitative real-time polymerase chain reaction (qPCR) is an essential tool for understanding animal cell’s response to developmental progression or to different experimental conditions at gene expression level. However the reliability of this method heavily lies on proper normalization (measuring a target and a reference gene’s expression from the same sample to correct for technical related variations).
    Our literature review aimed to summarize the articles addressing the most important livestock species in regards of reference gene stability used as normalizers for quantitative real-time polymerase chain reaction experiments. Stably expressing reference genes were categorized into 14 distinct groups according to gene function. The number of reference genes tested and the publication numbers according to years and the ranking algorithms were also noted.
    Counting showed that genes encoding ribosomal protein components are ranked as most stable in majority of cases and therefore should be taking into account for qPCR stable normalizer gene finding experiments.

  • Seasonal variations in somereproductive parameters of Dorper Rams in Hungary
    17-20
    Views:
    233

    The purpose of the present study was to test the hypothesis that season has an affect on semen quality and scrotal circumference of Dorper rams. The experiment was carried out with six Dorper rams aged between 15 and 18 month. Semen samples were collected with artificial vagina and volume, concentration (x 109/ml), total sperm number/ejaculate (x 109), mass motility (0–5), progressive motility (%), scrotal circumference (cm) was observed. Significant differences (P<0.05) were observed in concentration, total sperm number/ejaculate, scrotal circumference in different seasons. Volume was the highest in autumn (1.4±0.5 ml) and the lowest in the spring (1.3±0.4 ml). Concentration of semen was lower in spring (2.6±1.5 x 109) and summer (3.3±1.5 x 109) as compared to fall (4.1±1.1 x 109) (P<0.05). Regarding total sperm number/ejaculate (x 109), scrotal circumference (cm) all the seasons differed significantly (P<0.05), although the season had no effect on mass motility and progressive individual motility (P<0.05). In conclusion the present study showed that semen quality parameters and scrotal circumference of Dorper rams were better in autumn than in the other sea- sons.

  • Comparison of the technological background of aquaponic systems
    47-52
    Views:
    253

    Aquaponics is the combined culture of fish and plants in recirculating aquaculture systems, an ecologically sustainable horticultural production technique with long traditions.

    The objective of this study is to compare flood-and- drain, and the water crossflow system and examine the differences in the water quality, fish yield and plant growth parameters for Common carp (Cyprinus carpio) and basil (Ocimum basilicum). During the study, water quality parameters of two treatments were compared in temperatures, pH, EC and NON were significantly different (p <0.05). Leaf area of the basil plants grew to an average of 20.37 cm2 (± 9.02 cm2). The plants’ biomass production was significantly different (p< 0.05) in the two systems. The biomass production showed lower yield, 458.22 g (± 214.59 g) in the constant flow system that in the flood- and- drain system 692.9 g (± 175.82 g). Fish Growth parameters were better in constant flow system (FCR 5.48 g/g ± 0.19). However, the specific growth rate (SGR) demonstrated that fish grew faster in flood- and- drain system 1.38 %/day (± 0.29).

  • The impact of population management on urban and rural Hooded Crow populations
    119-123
    Views:
    61

    Hooded Crow (Corvus cornix), originally native to agricultural areas, has become widespread in urban areas in recent decades. However, this process has negative consequences on urban animals and humans. Due to these problems, the control of urban crow populations is needed. Crows also cause significant damage to wildlife management, and are constantly being controlled in rural areas as well. In this study, we compare rural and urban populations to find out whether hunting activities have a population reduction effect. In the rural population, the reduction is carried out by weapons and traps, while the urban crows are controlled using traps only. In both sample areas, crow nests were surveyed during the nesting period. 29 active nests were monitored in the rural area in 2021, and 39 in 2022. In the urban area, 44 nests were recorded in 2021 and 35 nests in 2022. In 2021, 30 individuals were removed in the rural area, and 84 in 2022. In the urban area, 223 individuals were removed in 2021 and 144 in 2022. Results show that the number of crows removed follows the number of active nests, so that the reduction of a given year is likely to have an effect on the following year's nesting population. Because traps mostly capture juvenile birds, reducing the breeding population in the city can only be achieved in the long-term. Considering this, it is likely that increased attention to population control can effectively maintain crow populations and reduce the problems they cause.

  • Some population genetics parameters of the present Hungarian Hucul Horse population
    15-22
    Views:
    148

    We examined the Hungarian population of the Hucul horse breed, under genetic protection, based on population genetic indicators until the year 2014 included. The evaluation was performed using the Endog programme based on the following indicators: inbreeding coefficient, average relatedness, the maximum number of generations, the number of full generations traced and offspring number. Our findings were as follows: the average inbreeding coefficient of the total population was 5.99%, average relatedness was 11.82%, the maximum number of generations was, on the average, 16.04%, and the number of full generations traced with reference to the whole population was 4.15% on the average. 40% of the whole population (723 individuals) did not have any offspring; 42% (759 individuals) attained an offspring of 1 or 2, while 3.4% (88 individuals) had a surviving offspring of 3. The highest offspring number according to the national database (92) was attained by one stallion.

  • Ragweed components in honey
    65-68
    Views:
    154

    The aim of this research was to prove that the syrup containing ragweed used for feeding the bees was transferred to the honey. To reach this goal we developed a method to analyse the volatile components of the samples. We applied two sample preparation methods. The first one was SPME (Solid Phase Micro Extraction) preparation from the headspace of all of the samples. In the second case only the raw leaves of the ragweed were extracted with n-hexane and dichloromethane to complete the SPME results. The measurements were performed on GC-MS equipment. Chromatograms and data evolution showed that the components of the ragweed were also present in honey so they were transferred by bees.

  • Routine microscopy examination of faecal samples as a tool for detection of common gastrointestinal parasites: a preliminary report from two Hungarian farms
    63-66
    Views:
    75

    Gastrointestinal parasitism in ruminant animals is a cause of major economic loss incurred by the livestock industry. Regardless of the frequency of the adopted therapeutic and prophylactic deworming strategies, the parasitic burden in a farm should be assessed regularly. One of the most widely used techniques to do so is the microscopic faecal egg examination and faecal egg counting method. Despite the technique being almost a century old from its first adoption, the principle behind the newer techniques of faecal egg examination is the same. This technique is still being used in routine farm screening and monitoring gastrointestinal parasitic load and faecal egg count reduction testing to assess the anthelmintic efficacy of the drugs used. Thus, the tool remains a choice for preliminary screening for important parasites and the subsequent deworming strategy. Our study here was part of a larger survey on the treatment efficiency as well as a broad epidemiological study of the trichostrongyle parasites in Hungary. We present a preliminary report on the detection of common gastrointestinal parasites from two farms in Hungary, including a species-specific confirmatory microscopy for Haemonchus contortus eggs.

  • Chromatometric comparison of Eurasian Collared Dove (Streptopelia decaocto) and Feral Pigeon (Columba livia domestica) feathers
    19-22
    Views:
    176

    Chromatometric examination of the plumage of birds is a poorly researched topic. We have approached this issue in primarily aspect of differences in plumage of species. Moulted feathers sample collection method has been increasingly used. Reliable identification of feathers becomes an increasingly important issue, hence need for an exact measurement-based methodology. Eurasian Collared Dove (Streptopelia decaocto) and Feral Pigeon (Columba livia domestica) primary, secondary and tail feathers were studied. Chromatometric parameters of feathers were measured in CIELAB color system and then statistical analysis (Independent samples t-test, Descriptive Statistics, Discriminant Analysis) was performed to compare the two species. Instrumental measurements has been confirmed the high similarity between colors of the two species, however species specific differences were also found. Lightless (L*) value were significantly characteristic of particular species, while the red/green (a*) and yellow/blue (b*) value had lower Predictive Power. We identified feathers and the variables which useable to separate the two species and determined the associated Confidence Intervals of these values. Our results may draw attention to a new potential direction for exact identification of the moulted feathers during sample collection.

  • The significance of local meteorological stations in research planning
    87-91
    Views:
    184

    The goal of research planning is to optimize human and material resources while maximizing efficiency. If there are databases that can be used as a substitute for own data collection, effective research can be facilitated by reallocating resources. In the case of environmental studies, the knowledge of the climatic conditions of the study period is known to be a key factor in research planning process.

     In the present study, the data of our meteorological station in our research area (known as “Szamárháti Tanya”, Kesznyéten, Hungary) was compared with the measurements of meteorological stations operated by the competent water authority. Stations were taken into the study within a 10 and 20 km radius over a period of 21 months, to determine which provided more relevant data from the area.

    During the evaluation of results, the relationship between the local and regional weather stations were determined, and deductions were made from the obtained results to support the decision which of the targeted investigations could be of greater benefit. 

  • The effect of immigration on some population genetic parameters of the Hungarian Hucul population
    91-96
    Views:
    125

    Population genetic indicators of the Hungarian Hucul population were calculated taking also into account the effect of imported horses.The birth year of the examined 3002 individuals ranged between 1871–2015. The last year involved in the examination was 2015, when the research was conducted on the stock under stud book control. The calculations on the population were made using the statistic indicators in the Endog programme, with and without the imported Polish horses. Figures were depicted using R software. Number of offspring of the Polish individuals was presented in tables; the distribution of the offspring per stud and per mare family, as well as the Nei’s genetic distance,were presented graphically.

  • The effect of different genotype cattle grazing on the nutrient content of saline grasslands vegetation
    46-50
    Views:
    172

    Maintaining saline grasslands in good condition, preserving their yield and diversity is important not only for the purpose of nature conservation, but also for farming. Therefore, the primary purpose of our study is to analyse the effect of pasture use of the smaller weight extensive and the larger weight intensive beef cattle on the grassland vegetation and nutrient content. In this way, we can answer the question whether grazing for nature conservation can be achieved with more profitable, more economical and more intense varieties.

    The tests were carried out in May 2016 and May 2017, in the Hortobágy National Park (Pap-ere and Zám puszta), where a total of 16 sample areas were analysed. These areas are grazed with extensive beef cattle (Hungarian grey) and mixed genotype of intensive cattle. The associations were selected along a moisture gradient, such as wet salt marsh (Bolboschoenetum maritimi) and drier saline meadow (Beckmannion eruciformis). All the vegetative material collected both years in May was analysed for the following parameters: dry matter, crude protein, crude fibre and life-sustaining net energy content. We compared the effects of medium grazing (0.46 livestock/ha) and abandonment on vegetation and nutrient content.

    We examined the effect of (i) grazing, (ii) different grasslands (salt marsh, saline meadow) and (iii) grazing of different cattle breeds (Hungarian grey, intensive beef) on the nutrient content of the vegetation of grasslands Based on our results, it was found that grazing had an impact on crude protein and life-sustaining net energy content. The highest crude protein content (12.75 m/m%) was obtained in the year 2017 in the area where higher density had been grazed for two years. For the lifesustaining net energy, the highest value (5.05 MJ/kg d.m.) was also obtained in 2017 and the lowest in 2016. Furthermore, it was found that there was no significant difference between the effect of the two cattle breeds on the parameters examined. Significant effects were observed only in the case of life-sustaining net energy: in the area of intensive beef cattle we received a higher value (5.15 MJ/kg body weight) than in the area with extensive beef cattle (4.96 MJ/kg body weight).

    Our results have also shown that cattle grazing is of the utmost importance for the maintenance of both wet and mesophilous habitats. Based on our three-year study, we can say that grazing by both extensive and intensive cattle breeds is suitable for the management of saline habitats.

  • Preliminary results of the combined production of duckweed Spirodela polyrhiza and common carp (Cyprinus carpio) in an aquaponic system
    83-89
    Views:
    64

    As a result of population growth, increasin amount of food is needed, and agriculture is under an increasing burden to meet these needs. Traditional agriculture is often attacked due to its environmental impact. We must find alternative, environmentally friendly ways to produce more food. Aquaponics is a closed system in which we can produce both fish and plants at the same time. Duckweed species are small, aquatic, floating plants belonging to angiosperms. It can potentially be an alternative protein source, due to its high protein content, good amino acid supply, and rapid growth. Under suitable conditions, it doubles its weight in 2–4 days, and can reach a yield of 30 t ha-1 year-1in dry matter. It forms a carpet on top of the water and can be found in slow-moving or still waters. Since they are resistant to a wide range of nutrient concentrations, they are also suitable for cleaning wastewater (such as eutrophicated lakes, sewage reservoirs, liquid manure storage). Fish feed is the primary nutrient source for aquaponic systems, which usually contains fishmeal. If duckweed can be used as an alternative for fishmeal in the feed, it could improve the sustainability of the aquaponic and aquaculture systems. In this study, the aim was to develop an optimal harvesting protocol for duckweed Spirodela polyrhiza under aquaponic conditions. In a four weeks experiments, four harvesting protocols were set up, a control where only biomass measurements were made, a 25% group where 25% of the biomass at the time of measurement was harvested, and a 50% and a 75% group where at the time of measurement 50% and 75% of the biomass was harvested. Three replicates were used per treatment. We weighed the biomass every week and removed the amount corresponding to the group. Based on the preliminary results, it can be said that more biomass was obtained in the groups with the 25% harvesting protocol and the control group.

  • Survival analysis of sow longevity and lifetime reproductive performance – Review
    75-80
    Views:
    251

    Sow 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.

  • Comparision of growth of mature all-female and mixed-sex Common carp (Cyprinus carpio L.) stocks in RAS
    65-68
    Views:
    404

    The common carp (Cyprinus carpio L.) is the most important fish species in Hungary, it is more than 70% of the total Hungarian fish production. The common carp production is important not only just in Hungary but in Middle-East Europe, as well as Southeast Asia. Majority of the production comes from fishpond culture. If the production sector wants to meet the increasing customer demands, there is need to intensify research on the intensive fish production opportunities for example all-female common carp technologies. The all-female technology is one of a genom-manipulation technology. Its production showed better growth rate than mixed-sex population in pond culture. Our experiment combined the recirculation aquaculture system (RAS) and the all-female common carp stocks intensification technologies. The reason for the experiment, is that there are no result about the growth of all-female common carp growth in RAS.

    The experiment used the „Tatai grey scale type” common carp stocks. We propagated two all-female stocks (T2 and T3) and a control group (TK). Due to technological characteristics of RAS, the water quality parameters were the same for all treatments and corresponded to the technological tolerance of common carp.

    The experimental period was from July 10, 2019 – November 20, 2019. Result of growth performance showed that the growth of mixed-sex stock was significantly higher than all-female stocks; (Control=3692.0±590.5g, T2=3438.8±415.4g, T3=3294.1±659.1g). Feed conversation ratio (Control=1.3±0.1 T2=1.5±0.2 T3=1.6±0.5) and SGR% (Control=0.8±0.0 T2=0.7±0.1 T3=0.7±0.1) were similar.

    By the results it can be said the all-female common carp technology has neither advantages nor disadvantages compared to the mixed-sex stock. The all-female technology can be beneficial if the consumers need female common carps. It is worth continuing the experiment and examine how the stocks will perform above 3kg body weight.