Insolation Levels Research Articles

Development of high-lycopene tomato hybrids using conventional breeding techniques and molecular markers

Relevance. High lycopene fruit content has been regarded as a very important genetic trait in tomato breeding. Use lycopene molecular markers in combination with conventional breeding techniques allowed us to create hybrids with high lycopene accumulation, excellent organoleptic qualities, high yield production and resistance to pathogens, and to effectively optimize our breeding programmes for commercial greehouses production.Material and Methods. In this study tomato samples including selected lines and hybrids with various allelic combinations of genes determining carotene accumulation, and other genetic traits, such as disease resistance and yield production were tested. Introgression of spontaneous and induced mutations was used to increase carotenoid levels (og and hp) and improve fruit technological qualities (nor, alc, rin). The research material was tomato collection, mutants, breeding lines and hybrids listed in the State Register Russian Federation tomato hybrids of breeding SS Agrofirm "Ilyinichna" VNIIO branch of the All-Russian Scientific Research Institute of Vegetable Growing – Branch of the FSBSI Federal Scientific Vegetable Center. DNA typing of fruit quality genes was performed at the Institute of Genetics and Cytology of the National Academy of Sciences of Belarus.Results. New domestic hybrids for industrial greenhouses, which characterised by improved organoleptic qualities and technological traits were developed with the help of phasedcross-breeding that allowed to combine the genes nor, rin, alc, leading to an extension of the shelf life with the genes B, og, hp1, etc., contributing to an increase in carotenoid content in fruits. It was established that for targeted selection and hybridization, despite the negative influence of the nor, rin, alc genes it is possible to raise the level of carotenoids to average values. Correlation between lycopene concentration in fruits and high temperature and level of insolation was confirmed. It was shown that pink-fruited forms contain significantly more lycopenethanred-fruitedones. Different all eliccombinations of structural genes involved in carotenoids biosynthesis and regulatory genes that provided maximal accumulation of lycopene in hybrid swithred and pink fruits were revealed. Hybrids with the combination of high concentrations of sugar (° Brix), dry matter and maximal lycopene values, combined defining excellent taste were selected: Prekrasnaiya lady, Olya, Quadrille, Victoria. New F1 hybrids one for industrial greenhouses: G950, G956, G960, Magistral and pink fruited G12897, surpassed the Dutch standard in productivity up to 21%, and in tastes/organoleptic qualities for 1-1.8 points.

Analysis of Solar Power and Energy Variability Through Site Adaptation of Satellite Data With Quality Controlled Measured Solar Radiation Data

Abstract Satellite-based solar power data is becoming more and more important because of its continuous temporal and spatial availability. However, its reliability can be enhanced through quality control and calibration against ground-based measurement data. Here, a holistic methodology is employed for the adaptation of satellite-based data for estimating solar energy. For the purpose, high-quality ground-based measurement data and satellite-based datasets are assessed across 12 sites in three small islands located in the Indian Ocean. Initially, both datasets go through a rigorous quality control process. A quantitative analysis of irradiance and insolation data is then conducted. Eventually, site adaptation of satellite-based data is performed using bias removal technique and statistical analysis of datasets. A set of seven statistical performance indicators is used to support the assessment. Analysis of datasets shows that adaptation of peak values should be performed separately. Results showed that despite the small surface areas of the islands studied, a spatial variation of insolation can be depicted. A temporal variation of insolation is also noted with a peak in the summer and low insolation levels in winter. Peak irradiance values tend to exceed solar constant for all sites. Variations of peak irradiance can only be noticed in ground-based measurement data. While insolation levels are comparable in the summer season for all the sites, insolation levels in the winter season are higher in the sites with lower latitudes. Calibration factors for peak irradiance, monthly and annual average irradiance as well as yearly insolation are presented.

Energy and Exergy Assessment of S-CO2 Brayton Cycle Coupled with a Solar Tower System

In this research, we performed energy and exergy assessments of a solar driven power plant. Supercritical carbon dioxide (S-CO2) Brayton cycle is used for the conversion of heat to work. The plant runs on solar energy from 8 a.m. to 4 p.m. and to account for the fluctuations in the solar energy, the plant is equipped with an auxiliary heater operating on hot combustion gases from the combustion chamber. The capital city of Saudi Arabia (Riyadh) is chosen in this study and the solar insolation levels for this location are calculated using the ASHRAE clear-sky model. The solar collector (central receiver) receives solar energy reflected by the heliostats; therefore, a radially staggered heliostat field is generated for this purpose. A suite of code is developed to calculate various parameters of the heliostat field, such as optical efficiencies, intercept factors, attenuation factors and heliostat characteristic angles. S-CO2 Brayton cycle is simulated in commercial software, Aspen HYSYS V9 (Aspen Technology, Inc., Bedford, MA, USA). The cycle is mainly powered by solar energy but assisted by an auxiliary heater to maintain a constant net power input of 80 MW to the cycle. The heliostat field generated, composed of 1207 rows, provides 475 watts per unit heliostat’s area to the central receiver. Heat losses from the central receiver due to natural convection and radiation are significant, with an average annual loss of 10 percent in the heat absorbed by the receiver. Heat collection rate at the central receiver reveals that the maximum support of auxiliary heat is needed in December, at nearly 13% of the net input energy. Exergy analysis shows that the highest exergy loss takes place in the heliostat field that is nearly 42.5% of incident solar exergy.

DSOGI-PLL With In-Loop Filter Based Solar Grid Interfaced System for Alleviating Power Quality Problems

This article deals with a dual second-order generalized integrator phase-locked loop (DSOGI-PLL) with in-loop filter-based control approach for a single-stage, three-phase three-wire solar-grid-interfaced system under abnormal grid voltage conditions, unbalanced load conditions, and varying solar insolation levels. The DSOGI with in-loop filter algorithm with enhanced filtering capability, employed for both voltages and currents, helps to attenuate the harmonics, eliminates dc offset, and estimates the sequence components. This algorithm elicits the fundamental component of highly nonlinear load current required for calculating the reference magnitude of the grid currents. Even during unbalanced load conditions, these fundamental components of currents are free from the dc offset and dominant harmonics of double frequency. In order to maintain the sinusoidal and balanced grid currents, the positive sequence voltages are estimated to get the accurate unit templates during the unbalanced and abnormal grid voltages conditions. Moreover, these positive sequence voltages are used by PLL to compute the phase required for the magnitude and the angle calculation of the currents and voltages. The dc-link voltage is maintained at maximum power point by an incremental conductance based technique. This system is simulated in MATLAB/Simulink environment. Test results on a developed laboratory prototype are observed in accordance with the standard of the IEEE-519.

Feasibility of hydrogen-air energy storage gas turbine system for the solar power plant in Yakutsk region

For the solar power plants unsteady power generation is one of the main drawbacks, which must be taken into account. The hydrogen-air energy storage gas turbine system is considered in this paper for the Yakutsk region in Russia. This place with no centralised electrical grid has enough solar insolation level to supply with the power the settlement of several households with the average power consumption of 3 kW. The calculations show that 52 photovoltaic panels of the specific type are optimal number from the power balance data. It is supposed that in the months with the surplus of solar power the system works in generation mode and in the other months in storage mode. Also some reserve is planned for the supply during night in the storage mode by the gel batteries. After that the volumes and masses were determined for the reservoirs containing air, hydrogen and oxygen for the energy storage. The air reservoir for the compressed air energy storage (CAES) has the biggest volume 121 m3 according to the calculations. The gas turbine (GT) of 5 kW suits the system in the power generation mode. The special hydrogen-air combustion chamber is required for the GT unit.

МОДЕЛИРОВАНИЕ ЗАКОНОВ РАСПРЕДЕЛЕНИЙ МОЩНОСТИ ВЕТРОЭНЕРГЕТИЧЕСКИХ И СОЛНЕЧНЫХ СТАНЦИЙ

Актуальность. Мощность, выдаваемая генерирующими станциями на возобнов­ляемых источниках энергии, ветроэнергетическими и солнечными, зависит от состояния природной среды в конкретной географической точке, доминирующих скоростей ветра и уровня солнечной инсоляции. Закономерности, характеризующие скорости ветра и солнечную инсоляцию, зависят от местности, времени года и носят вероятностный характер. Это значит, что вероятностный характер имеет и мощность, выдаваемая генерирующими станциями на возобнов­ляемых источниках энергии. Риски, связанные с неточным знанием вероятностных закономерностей, описывающих эти источники, а также непредсказуемость (неопределённость) природной среды являются причинами, из-за которых системные операторы не учитывают такие станции в расчетах баланса мощности. Это, в свою очередь, не позволяет рассматривать генерирующие станции на возобновляемой энергии как полноценных участников рынка, прикрывая поток инвестиций в подобные проекты. Уточнение законов распределения вероятностей скорости ветра и солнечной инсоляции на основании статистического анализа соответствующих рядов измерений, а также уточнение на их основе законов распределения вероятностей для мощности соответствующих электростанций может оказать существенную помощь системному оператору при прогнозировании мощности, генерируемой станциями на «зеленой» энергии. Цель: построение моделей законов распределения, наилучшим образом описывающих результаты наблюдений скорости ветра и солнечной инсоляции, а также моделей законов распределения для вырабатываемой мощности ветроэнергетической и солнечной станций. Методы: методы оценки параметров законов распределения, методы проверки статистических гипотез. Результаты. Показано, что в отличие от наиболее часто используемого в этих целях закона Вейбулла, наилучшими моделями законов распределения вероятностей для рядов измерения скорости ветра и солнечной инсоляции на рассматриваемой территории являются законы семейства бета-распределений 3-го рода, а также смеси этих законов. То же самое касается описания распределения вероятностей мощности ветроэнергетической и солнечной станций. Построены модели законов распределения (по месяцам) для скорости ветра, солнечной инсоляции и мощности соответствующих станций. Показано, что на основании закона распределения скорости ветра и математических соотношений, связывающих мощность со скоростью ветра, можно строить хорошие модели для распределений вероятностей мощности ветроэнергетических станций. Построенные модели могут использоваться в качестве вспомогательного инструмента для системных операторов энергосистем для прогнозирования выдаваемой мощности.

Habitat conditions, spatial distribution and trichome morphology of different species of Tillandsia growing on trees on the Ilha Grande Island, Brazil

Epiphytes living in the canopy face the problem of being exposed to varying levels of air humidity, temperature and insolation, according to both local climate and growing site conditions. This study addresses interrelationships between a) vertical distribution of Tillandsia species on phorophytes of Ilha-Grande Island in tropical Brazil; b) micrometeorological conditions at the different epiphyte habitats and growing sites; c) diurnal changes in plant water content and d) morphological traits of Tillandsia leaves with respect to absorptive scales. For this purpose, five vertical zones of different height and exposure were defined within the canopy, which are characterized by specific epiphyte associations. It was found that the Tillandsia species are heterogeneously distributed within tree canopies. The most exposed sites are colonized almost exclusively by T. usneoides whereas less exposed zones are settled by different assemblages of all other considered Tillandsia species. Microsite conditions (temperature and humidity) were shown to be substantially different, with quite extreme conditions at the sites preferred by T. usneoides. Despite its apparently stressful habitat, T. usneoides showed the lowest decrease of daily water content. All considered Tillandsia species differed significantly with respect to size and density of their absorptive scales. Also, density and size of scales differed within the leaves in a species-specific manner. Tillandsia usneoides was distinctly different from all other considered species by showing the longest scales and a high scale density which was uniform over the leaves. The results demonstrate the unique ability of T. usneoides to cope with drought stress. The outcomes support the assumption that leaf and scale morphology of Tillandsia are correlated with habitat. Probably, a dense mat of filiform leaves covered with scales showing long wing cells – as shown by T. usneoides – is particularly suitable for harvesting atmospheric water.

Performance analysis of solar updraft tower using Ansys fluent

The solar updraft tower (SUT) is a renewable energy power plant design concept for generating electricity by utilizing convective air flow due to low temperature heat absorption from incoming solar radiation. A parametric study on the performance power output of the SUT at various canopy angles and different insolation levels were carried out to investigate the relationship between them with respect to key parameters i.e. in terms of updraft tower velocity, temperature, pressure and height to choose turbine position for maximum air velocity absorption and energy conversion using Ansys-fluent software version 15 for analysis. The results obtained were analyzed comparatively to draw conclusions. The results identified using simulation software mentioned above were validated with earlier results and identified significant improvement in the power generated at various collector angles, when compared with the earlier works on SUT.

Single Column Model Simulations of Icing Conditions in Northern Sweden: Sensitivity to Surface Model Land Use Representation

In-cloud ice mass accretion on wind turbines is a common challenge that is faced by energy companies operating in cold climates. On-shore wind farms in Scandinavia are often located in regions near patches of forest, the heterogeneity length scales of which are often less than the resolution of many numerical weather prediction (NWP) models. The representation of these forests—including the cloud water response to surface roughness and albedo effects that are related to them—must therefore be parameterized in NWP models used as meteorological input in ice prediction systems, resulting in an uncertainty that is poorly understood and, to the present date, not quantified. The sensitivity of ice accretion forecasts to the subgrid representation of forests is examined in this study. A single column version of the HARMONIE-AROME three-dimensional (3D) NWP model is used to determine the sensitivity of the forecast of ice accretion on wind turbines to the subgrid forest fraction. Single column simulations of a variety of icing cases at a location in northern Sweden were examined in order to investigate the impact of vegetation cover on ice accretion in varying levels of solar insolation and wind magnitudes. In mid-winter cases, the wind speed response to surface roughness was the primary driver of the vegetation effect on ice accretion. In autumn cases, the cloud water response to surface albedo effects plays a secondary role in the impact of in-cloud ice accretion, with the wind response to surface roughness remaining the primary driver for the surface vegetation impact on icing. Two different surface boundary layer (SBL) forest canopy subgrid parameterizations were tested in this study that feature different methods for calculating near-surface profiles of wind, temperature, and moisture, with the ice mass accretion again following the wind response to surface vegetation between both of these schemes.

The case study of a photovoltaic plant located at the university of L’Aquila: An economic analysis

Solar energy has contributed significantly to the energy transition towards a low carbon society. Public offices – including universities – are being called to participate in the solar energy transition, as the availability of their rooftops represents an opportunity. The present study aimed at evaluating the economic feasibility of a photovoltaic (PV) plant at the University of L’Aquila, approximately 10 years after an earthquake devastated the region. The reconstruction process is ongoing, and a solar PV plant could potentially move the city in a sustainable direction. The development of sustainability models requires the economic verification of relevant projects and a complete list of indicators for decision-makers. The present work found that a 210 kW PV plant at the University of L’Aquila would reduce emissions by 184.9 t CO2eq/year and generate 1500 € profits for each kW installed; and a 115 kW PV plant would reduce emissions by 101.5 t CO2eq/year and generate profits of 1370 € for each kW installed. The analysis of alternative scenarios gave solidity to the results, confirming the pivotal role of the share of self-consumed energy. Level of insolation and plant size were also found to significantly influence economic performance. Finally, the adoption of a bonus to encourage the production and self-consumption of energy may increase investors’ attention towards environmental issues.

Numerical Modeling of a Photovoltaic/Microchannel Direct-Expansion Evaporator for a CO2 Heat Pump

Abstract A numerical model of a PV/microchannel direct-expansion evaporator for a CO2 heat pump is developed and validated with experimental data from the literature. The effects of degree of superheating, CO2 mass flux, and evaporation temperature on the amount of heat absorbed, pressure drop in the microchannel evaporator, PV temperature, and electrical efficiency are analyzed. The analysis shows that increasing the degree of superheating decreases the amount of heat absorbed, has minimal effect on the PV temperature (for superheating <15 °C), but reduces the pressure drop. The variation of CO2 mass flux has a minimal effect on the amount of heat absorbed and the PV temperature, but the pressure drop increases with increasing CO2 mass flux. Increasing the evaporation temperature decreases the amount of heat absorbed, reduces the pressure drop, and increases the PV temperature. For average ambient conditions for Fargo, North Dakota, a 5–10 °C of superheating at the evaporator outlet, an evaporator temperature between −5 and +5 °C, and a CO2 mass flux of 330–550 kg · m−2 · s−1 balance maximizing the heat absorption while minimizing the pressure drop. To maximize the PV efficiency, lower evaporation temperatures should be used. At an evaporation temperature of 0 °C and an insolation level of 1000 W · m−2, the CO2 microchannel evaporator causes a 23 °C reduction in PV panel temperature which corresponds to a 1.44% absolute increase in PV efficiency.

A Cuckoo MPPT based SMC Control for Grid tied PV System

Maximum power point techniques (MPPT) are used in photovoltaic system to make full utilization of PV array output power. The output power of PV array is always changing with weather conditions i.e., solar irradiation and atmospheric temperature. PV cell generates power by converting sunlight into electricity. The electric power generated is proportional to solar radiation. PV cell can generate around 0.5 to 0.8 volts. During cloudy weather due to varying insolation levels the output of PV array varies. The MPPT is a process which tracks the maximum power from array and by increasing the duty cycle of the DC-DC boost converter, the output voltage of the system is increased. This paper presents the cuckoo mppt technique for PV system along with SMC controller methods in grid connected photovoltaic (PV) systems for optimizing the solar energy efficiency

Tests of an Absorption Cooling Machine at the Gijón Solar Cooling Laboratory

Final energy consumption in the residential sector is increasing, even in countries with favourable climate conditions and technological capacity to promote the use of renewable resources and energy efficiency. Air conditioning systems based on absorption cycles are common solutions in solar assisted installations. In this paper, the main characteristics of the Gijón Solar Cooling Laboratory (GSCL) are summarized, showing its ability to test cooling machines with a variety of heat sources and sinks, as well as different technologies and strategies. An absorption machine with internal energy storage in LiCl salts has been tested at the GSCL, measuring power and temperatures as a function of time during several charging and discharging cycles. During the charging cycles, the operation of the machine was analysed for various hot temperatures and power values. In the discharging cycles, special attention was paid to the refrigeration capacity produced for various chilled water temperatures. The results led to coefficient of performance COP values that are in line with those expected for this technology. Satisfactory operation of the system seems difficult at activation temperatures below 75 °C. For low levels of insolation, this limitation could lead to an increase in auxiliary energy consumption.

The economic viability of photovoltaic systems in public buildings: Evidence from Italy

Abstract Photovoltaic (PV) systems transform solar irradiation into electricity, thereby substituting for traditional energy sources and reducing environmental pollution. The present work evaluates a developed market (Italy) in which subsidies have been re-introduced for PV plants with a nominal capacity above 20 kW through the FER1 (renewable energy sources) Decree. The discounted cash flow (DCF) methodology is applied to several cases of PV plants in public buildings, in order to determine the value of several critical variables (i.e. level of insolation, plant size, share of self-consumption, investment cost, electricity purchase price). In particular, differences in net present value (NPV) and discounted payback time (DPBT) between subsidy and no-subsidy scenarios are quantified. Break-even point (BEP) analysis is used to define the share of self-consumed energy for which NPV is positive. This share is found to range from 9 to 28% in 105 kW plants and from 10 to 35% in 25 kW plants. In addition, the results verify profitability in almost all of the baseline case studies and only half of the alternative scenarios (involving no subsidies). The estimated profits are consistent with investments aimed at increasing the share of self-consumed energy.

ВЛИЯНИЕ ЦВЕТА КОНТЕЙНЕРА НА РОСТ ПОСАДОЧНОГО МАТЕРИАЛА THUJA OCCIDENTALIS 'SMARAGD'

The article presents the results of a three-year study of the growth of thuja seedlings in plastic pots of three colors. Differences were found between heating the surface of multi-colored containers and the substrate. The color of the containers affects plant growth in the middle of the vegetative period, when air temperature and insolation level reach maximum values. The plants grown in green pots showed maximum growth indicators. However, during the statistical processing of the data obtained significant differences have not been found. Analysis of variance in the first year of cultivation revealed the presence of a factor — the color of the container impact on the thuja growth in diameter at 22% of the total set of influencing factors. This effect was leveled later. Correlation analysis has showed high relationship between the surface temperature of the pot and substrate with the north (r = 0.95-0.98), the south (r = 0.84-0.99), the west (r = 0.96-0.99) sides, and the average with the east side (r = 0.29-0.81). No differences in container colors were found. Analysis of the activity of salts in the substrate of containers shows thatthe substrate has a different content of macro- and microelements in containers of three colors after the first year of cultivation. Apparently, high temperature in the black container leads to an increase in the rate of chemical reactions, as well as a more intensive leaching of the main nutrients from the substrate. The influence of the “container color” factor on the content of available macro- and micronutrients after the first year is 37.5% of the total population. By the end of the experiment, the strength of this factor did not exceed 5%.

Precise mass and radius of a transiting super-Earth planet orbiting the M dwarf TOI-1235: a planet in the radius gap?

We report the confirmation of a transiting planet around the bright weakly active M0.5 V star TOI-1235 (TYC 4384–1735–1, V ≈ 11.5 mag), whose transit signal was detected in the photometric time series of sectors 14, 20, and 21 of the TESS space mission. We confirm the planetary nature of the transit signal, which has a period of 3.44 d, by using precise RV measurements with the CARMENES, HARPS-N, and iSHELL spectrographs, supplemented by high-resolution imaging and ground-based photometry. A comparison of the properties derived for TOI-1235 b with theoretical models reveals that the planet has a rocky composition, with a bulk density slightly higher than that of Earth. In particular, we measure a mass of Mp = 5.9 ± 0.6 M⊕ and a radius of Rp = 1.69 ± 0.08 R⊕, which together result in a density of ρp = 6.7− 1.1+ 1.3 g cm−3. When compared with other well-characterized exoplanetary systems, the particular combination of planetary radius and mass places our discovery in the radius gap, which is a transition region between rocky planets and planets with significant atmospheric envelopes. A few examples of planets occupying the radius gap are known to date. While the exact location of the radius gap for M dwarfs is still a matter of debate, our results constrain it to be located at around 1.7 R⊕ or larger at the insolation levels received by TOI-1235 b (~60 S⊕). This makes it an extremely interesting object for further studies of planet formation and atmospheric evolution.

Assessing the environmental sustainability of an emerging energy technology: Solar thermal calcination for cement production

Cement production is a highly energy-intensive process, contributing 7% to global CO2 emissions. Over 80% of the energy used in cement production is consumed by the calcination process. This paper considers a novel solar thermal technology for calcination, to investigate if it could help mitigate the climate change and other environmental impacts from cement production on a life cycle basis. The following three solar options are compared to conventional fossil-fuel calcination via life cycle assessment: a full solar system, which provides all the required thermal energy, and two hybrid systems, where the solar system provides 14% and 33% of the thermal energy, respectively. The results show that all three solar options have lower impacts than conventional calcination in 14 out of 17 categories. The full solar system is the best alternative, with major reductions in climate change (48%), fossil depletion (75%), photochemical ozone formation (92%) and terrestrial ecotoxicity (79%). Based on insolation levels in different parts of the world, the solar systems could be applied to 26% of current global cement production. This would reduce the climate change impact by 15–40%, as well as most other impacts by 14–87%, depending on the fuel mix. However, a limiting factor might be two times greater land occupation than by the conventional process. Furthermore, the solar system has higher human toxicity-cancer (102%) and metals and minerals depletion (6%) due to the construction of solar facilities. Coupling conventional calcination with carbon capture and storage (CCS) is more efficient in reducing the climate change impact (63%) than the solar system (48%) relative to conventional calcination without CCS. However, adding CCS to the solar calciner would still be a better option, decreasing the impact by 81% relative to conventional calcination without CCS. These findings will be of interest to the solar and cement industries as well as other industrial sectors using high-temperature processes.

The Impact of COVID-19-Related Measures on the Solar Resource in Areas with High Levels of Air Pollution

SummaryRestrictions enacted to reduce the spreading of COVID-19 have resulted in notably clearer skies around the world. In this study, we confirm that reduced levels of air pollution correlate with unusually high levels of clear-sky insolation in Delhi, India. Restrictions here were announced on March 19th, with the nation going into lockdown on March 24th. Comparing insolation data before and after these dates with insolation from previous years (2017 to 2019), we observe an 8.3% ± 1.7% higher irradiance than usual in late March and a 5.9% ± 1.6% higher one in April, while we find no significant differences in values from previous years in February or early March. Using results from a previous study, we calculated the expected increase in insolation based on measured PM2.5 concentration levels. Measurements and calculations agree within confidence intervals, suggesting that reduced pollution levels are a major cause for the observed increase in insolation.

DC-DC converter as a maximum power point voltage tracker.

In this paper, the maximum power point voltage tracker is designed and operated with the DC variable resistive load. The DC-DC converter technique is used for the design. The designed tracker operates as a DC-DC converter down. The designed tracker is a smart type; this is due to the use of programmed microcomputer to control the tracker circuits. The tracker contains three main circuits, sensing, drive and the power circuit. The designed tracker is constructed suitable to use with the photovoltaic power system (PVPS). The tracker is tested in the laboratory under different load levels at fixed insolation level.

DISTRIBUTION OF DICTIOCAULOSIS OF CATTLE IN COMMODITY FARMS OF SUMY REGION

The article presents data on the establishment of the spread of dictyocaulosis of cattle in farms of different production facilities of Sumy region. According to researchers, a prominent place among the pulmonary helminthiasis of domestic and wild ruminants belongs to dictyocaulosis. Currently, nematodes are an unresolved problem in cattle farms. The work was performed during 2019 on the basis of the laboratory of the Department of Epizootology and Parasitology of Sumy National Agrarian University, as well as in the conditions of livestock farms of Sumy region, which specialize in the production of marketable milk. Feces were collected from animals systematically throughout the year in different seasons, followed by their study by standardized methods of Berman and Orlov. The intensity of the invasion was determined by counting the number of larvae in 1 g of feces at low magnification. Determination of the intensity of contamination of environmental objects by dictyocaul larvae was performed using the method of M.O Romanenko.
 In the course of research and analysis of statistical reporting, it was found that dictyocaulosis is one of the three most common invasive diseases diagnosed in cattle in Sumy region. It has been proven that the frequency of diagnosing cases of respiratory pathology of various etiologies has increased in livestock farms that are unfavorable for dictyocaulosis. A clear seasonal dynamics of dictyocaulosis in livestock of different age categories was established: in calves under one year of age, the maximum lesion of Dictyocaulus viviparus was registered in June, with an invasion extent of 69.21%. In calves under two years of age, dictyocaulosis was registered in spring and autumn (the extent of invasion in April was 62.1%, in late September-early October - 51.4%). In a study of cattle older than two years, the highest extent of dictyocaulous invasion was found in spring and autumn, respectively, 59.7% and 35.1%. The peak of the outbreak was recorded in late autumn, in contrast to the animals of younger age categories. The highest intensity of infestation is found in calves under one year of age in summer, in older age groups - in autumn. When determining the contamination of environmental objects with larvae of Dictyocaulus viviparus, the highest rates were observed on the vegetation of pastures, near water sources with insufficient levels of insolation. Contamination by larvae of Dictyocaulus viviparus of the surface layers of soil and water sources on pastures was lower and amounted to 52.5 and 32.5 %, respectively.