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Urban hydrology research fundamentals for waste management practices Full text
2019
Pehme, K.-M., Estonian Univ. of Life Sciences, Tartu (Estonia) | Burlakovs, J., Estonian Univ. of Life Sciences, Tartu (Estonia);Linnaeus Univ. (Sweden);University of Latvia, Riga (Latvia) | Kriipsalu, M., Estonian Univ. of Life Sciences, Tartu (Estonia);University of Latvia, Riga (Latvia) | Pilecka, J., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Grinfelde, I. [and three others], Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia)
The urbanization and increasing growth of planet’s population accumulates significant volume of disposed waste as well as increases risks on human health and environmental safety. Landfill systems are the dynamic, living in space and time, potentially harmful entities that must be managed in as careful and smart way as possible. There are many studies related to landfill emissions such as leachates and methane. However, there is a need for advanced understanding of landfill hydrological regime and risks related to climate change and associated changes of hydrological cycle. The comprehensive studies about the urban hydrology are available; however, application to landfill management is fragmentary and inconsistent in several aspects. Landfill in long term has an impact on hydrological cycle. The heterogeneous land surface is one of aspects; however, there are still unanswered questions about the urban environment impact on water balance components. The aim of this study is to describe fundamentals of landfill hydrology in urban hydrological response unit context as well as evaluate the potential risks to environment and human health related to landfill geomorphology and hydrological balance in temporal climate conditions. The landfill hydrological cycle has similarities with urban hydrological cycle; however, there are additional components related to landfill specification, e.g., irrigation or leachate recirculation as well as total produced leachate.
Show more [+] Less [-]Assessment of land use change scenario to increase primary productivity function at local scale Full text
2019
Valujeva, K., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia);Wageningen Univ. and Research (Netherlands) | Nipers, A., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Lupikis, A., Latvian State Forest Research Inst. Silava, Salaspils, Latvia | Pilecka, J., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Schulte, R.P.O., Wageningen Univ. and Research (Netherlands)
The global population has begun to rise exponentially; therefore, the demand for bioresources including food and fibre is increasing. An increasing demand for food and fibre necessitates more sustainable use of natural resources especially for soilbased ecosystem services. In this context, Functional Land Management was developed to optimize agricultural soilbased ecosystem services to meet both agricultural and environmental targets simultaneously. The aim of the research is to evaluate unmanaged agricultural land use change impact on primary productivity function in three parishes in Latvia by using Functional Land Management framework. Evaluation of primary productivity function was accomplished for both sectors agriculture and forestry by using profit and working hours as a proxyindicators. Production of vegetables and perennial plantations has higher supply of primary productivity function comparing to other land uses. Land use changes affect all soil functions that we expect from our land, especially primary productivity function. After applying land use changes, an increase in profit is higher in Liezere parish for both areas on mineral soils (7.1%) and areas on organic soils (5.2%); while an increase in working hours is higher in Usma parish: 36.6% in areas on mineral soils and 1.0% increase in areas on organic soils. Shortterm benefits are received from agricultural land, while forest land provides long-term return which increases over time but can only be obtained after reaching the age of felling. Before applying land use changes or changes in management practices we have to consider other soil function and national commitments.
Show more [+] Less [-]Effect of salt treatment on yield and quality of frozen cod loins Full text
2019
Liorancas, V., Klaipeda State Univ. of Applied Sciences (Lithuania)
Study has been performed in fish processing plant ‘X’ with an aim of on purpose to investigating the influence of salt treatment on yield and quality of frozen cod loins. Samples were soaked in 0.8, 1.2, 10% NaCl concentrations in brine before being frozen. In this study, the cod loin’s weight loss during refrigeration, defrosting and cooking was calculated and sensory analysis was carried out. It was found that the soaking in brines affected higher weight of cod loins after freezing. In the control group it decreased by 1.14%, but the S0.8, S1.2 and S10 groups had the weight gain, respectively 3.41, 4.72 and +4.78%. Although after the defrosting and cooking the control group had the lowest weight losses, considering the losses of all operations, it was found that the largest weight loss was in the control group and in the S0.8 group, respectively 31.19% and 31.29%, while the lowest in the S1.2 and S10 groups – 30.49 and 30.06% (p is less than 0.05), respectively. Salt treatment did not affect the taste and odour, but improved the cod loin’s texture properties. Based on these results, salt treatment is considered as an effective way to improve the yield and quality of frozen cod loins.
Show more [+] Less [-]Evaluation of a headspace solid–phase microextraction with different fibres for volatile compound determination in specialty coffee brews Full text
2019
Laukaleja, I., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Kruma, Z., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia)
The aroma of coffee is the main quality factor. Compounds with floral, fruity, citrus and sometimes fermented aroma notes are defined as high quality characteristics for the specialty coffee brew. Commercial coffees mostly are at medium roast and the aroma profile is focused on balanced chocolate, caramel, toasted bread and almond bitterness aroma notes. These sensory characteristics set the focus for volatile compound profile analysis by Headspace solidphase microextraction (HS-SPME). The most popular fibres for commercial coffee aroma profile analysis are DVB/ CAR/PDMS, CAR/PDMS, PDMS/DVB and PA. There is limited research done about specialty coffee aroma profile and evaluation of more suitable fibres for solid-phase microextraction. The aim of the research is to evaluate the aroma composition of specialty coffee brews using different SPME fibres. Results demonstrated that CAR/PDMS fibre, compared to other fibres, can extract significantly more volatile compounds with higher peak areas in all chemical compound groups, except phenols. The CAR/PDMS was the only fibre which could detect all 17 important volatile compounds for specialty coffee. In conclusion, from the given research evidence, CAR/PDMS fibre is suggested as the most suitable SPME fibre coating for volatile compound extraction for specialty coffee brew import. The result provides evidence for improved specialty coffee aroma profile analysis by SPME.
Show more [+] Less [-]Determination of organic acids in honey samples from Latvian market by high-performance liquid chromatography Full text
2019
Keke, A., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Cinkmanis, I., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia)
Determination of organic acids in honey samples from Latvian market by high-performance liquid chromatography Honey is a naturally sweet product, which is produced by honeybees (Apis mellifera). Honey is a natural source of antioxidants and has been known to mankind since ancient times. Honey contains approximately 200 different compounds. Organic acids can be used as an indicator to detect the freshness, authenticity and acidity of honey. The aim of this research was to determine and quantify organic acids such as oxalic, L-tartaric, D-quinic, L-malic, L-ascorbic, citric, fumaric and succinic in honey samples from Latvian market u sing high-performance liquid chromatography. The chromatographic separation of organic acids was carried out with PerkinElmer C18 (4.6 mm Í 250 mm I.D, particle size 5 mm) analytical column at the temperature of 35 °C in wavelength at 210 nm. The obtained results showed that the analysed honey samples contain L-tartaric, D-quinic, L-malic, L-ascorbic, citric, fumaric and succinic acids. The concentration of these acids was found to be variable. Oxalic acid was not detected in the analysed honey samples. L-tartaric acid was the main acid in all analysed honey samples.
Show more [+] Less [-]Preliminary study of bovine colostrum quality in Latvia Full text
2019
Baltrukova, S., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia);Institute of Food Safety, Animal Health and Environment “BIORˮ, Riga (Latvia) | Zagorska, J., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Eihvalde, I., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia)
Bovine colostrum is a mammary gland secret which, due to its high immunoglobulin concentration, is necessary for the transfer of passive immunity to the calf, preventing diseases caused by microbial infections in the newborn ruminants. Colostrum, however, may contain pathogens and can be an infection transmitter, affecting morbidity and mortality rates of calves in the farms. Total plate count and immunoglobulin concentration are two main factors affecting colostrum quality, therefore the aim of the study was to analyse Latvian dairy herd colostrum quality. Colostrum was collected from Holstein Black cows within the first six hours after calving, lactation period of animals ranged from 1st to 4th lactation. Colostrum samples (n=51, 50 mL) were collected from December 2018 to February 2019. Immunoglobulin concentration (n=51) was defined by colostrometer (COLOSTROMETERtm Biogenics, USA), total solids content by optical refractometer (Model BX, UK). Staphylococcus spp. colony–forming unit (CFU) (LVS EN ISO 6888-1+A1:2007), the presence of Listeria spp. (LVS EN ISO 11290-1+A1:2007) and Salmonella spp. (LVS EN ISO 6579-1:2017) were examined in the colostrum samples (n=20). Despite the high immunoglobulin concentration in the analysed samples, our research findings demonstrate suboptimal colostrum quality received by calves. That indicates the necessity for regular colostrum quality control and better management practise providing on the farm.
Show more [+] Less [-]Health status of gene fond donor cows of Latvian native breeds Latvian Brown and Latvian Blue Full text
2019
Ringa-Karahona, G., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia);Institute of Food Safety, Animal Health and Environment “BIORˮ, Riga (Latvia) | Sematovica, I., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Antane, V., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Mangale, M., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia)
The preservation of local animal breeds is a topical theme in recent years. Latvian Brown (LB) and Latvian Blue (LZ) cow breeds are exhausting and must be preserved. It can be performed by the use of multiple ovulation and embryo transfer (MOET). The difficulties exist in choosing the gene-fond (GF) cows as donors caused by the small number of animals. Twenty-three cows were intended for donor cow’s role from different herds until September 2018, and twenty of them were accepted. Anamnesis, clinical examination, blood morphology (13 parameters) and biochemical indices (19 parameters) were analysed before MO induction. Three cows were rejected because of ovarian cysts or pyometra, negative energy balance (NEB) (glucose is less than 2.3 mmol LE−1 simultaneously with elevated ß-hydroxybutyric acid is greater than 1.4 mmol LE−1) and elevated (p is less than 0.05) number of leukocytes (28.20 x109 LE−1). More than 52.6% of cows had a repeated artificial insemination before the last parturition, and 5.3% of cows had lifeless offspring in the last parturition. The 1st and 2nd lactation cows were healthier than older cows (p is less than 0.05). The amount of albumins, cholesterol, triglycerides and Na, K, P, Cl, Mg was significantly different in donors with and without successfully obtained embryos (p is less than 0.05). In conclusion, not only acceptable clinical health but also the cow metabolic status is a decisive factor for success of MOET.
Show more [+] Less [-]The effect of dietary β-glucans supplements on the haematological parameters of the sea trout Full text
2019
Revina, O., Institute of Food Safety, Animal Health and Environment “BIORˮ, Riga (Latvia);Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia);Institute of Food Safety, Animal Health and Environment “BIORˮ, Riga (Latvia) | Revins, V., Institute of Food Safety, Animal Health and Environment “BIORˮ, Riga (Latvia) | Cirule, D., Institute of Food Safety, Animal Health and Environment “BIORˮ, Riga (Latvia) | Valdovska, A., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia)
In recent years, the effective immunostimulating properties of β-glucans have been widely proven not only in mammals, but also in aquatic animals. The aim of this study was to determine the effect of dietary β-glucan supplements on the percentage of individual types of leukocytes and the haematocrit of the sea trout (Salmo trutta L.). Investigations were performed at the state fish farm ‘Tome’, hatchery ‘Pelči’ of the Institute of Food Safety, Animal Health and Environment ‘BIOR’, during a six month period (September 2018 – February 2019). On the basis of feeding with immunostimulant diets, a total of 15 000 sea trout were assigned into five groups. For blood collection healthy fish were randomly selected once a month, five 5 individuals from each group. Blood smears were made to determine the leukocyte differential count. Sampling was done once a month (September 2018 – January 2019) (n=125). Haematocrit was determined by the standard microhaematocrit method. Sampling was done once a month (January 2019 – February 2019) (n=50). We concluded that the dietary β-glucan supplements can improve the haematocrit level and effect the percentage of individual types of leukocytes of the sea trout, stimulation of the preparation for parr-smolt transformation.
Show more [+] Less [-]Histopathological changes in liver of elks with Parafasciolopsis fasciolaemorpha invasion Full text
2019
Bergmane, B., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Berzina, D., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Visocka, A., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia)
Parafasciolopsosis is a parasitological disease which is caused by the liver fluke Parafasciolopsis fasciolaemorpha. This parasite which belongs to herbivores often causes invasion in elks (Alces alces). The aim of our study was to diagnose the parasite and investigate what kind of histopathological changes it caused in the liver tissue. The study took place in Latvia University of Life Sciences and Technologies, Faculty of Veterinary Medicine, Laboratory of Comparative Pathology and Laboratory of Parasitology. During the study from 2017 to 2018 we collected liver samples and faeces from 46 felled elks of different age and gender, from all over Latvia. Ten grams of faeces were examined for trematode eggs by sedimentation method and a section of liver was examined for the presence of flukes and the histological structure of the liver. In this study Parafasciolopsis fasciolaemorpha were found in 11 samples of liver from 46 elks, with invasion extensity of 24%. The histopathological examination of the liver samples revealed fibrosis, proliferation of bile ducts, pericholangitis, calcerous deposits in bile ducts and other notable histological changes in the liver tissue that can cause hepatic trematodes.
Show more [+] Less [-]Above-ground and seed bank weed biodiversity comparison in conventional and organic farming systems in Poland Full text
2019
Berbec, A.K., Institute of Soil Science and Plant Cultivation, State Research Inst., Pulawy (Poland) | Feledyn-Szewczyk , B., Institute of Soil Science and Plant Cultivation, State Research Inst., Pulawy
The assessment and conservation of agricultural biodiversity is one of the current goals of European Union policies, which are reflected in European Biodiversity Strategy. The biodiversity of soil seed bank and above-ground weed flora were investigated in spring cereals in organic and conventional farming system. The study was carried out between 2012 and 2014. Species of above-ground wild flora were counted on a surface of 1 square m in the field. Soil for seed bank evaluation was taken from the field and evaluated by seedling emergence method in a greenhouse. There were no significant differences in number of species between two communities. Biodiversity of weed community, described by Shannon’s diversity index and Simpson’s dominance index, was significantly better maintained in the soil seed bank than in above-ground flora in both farming systems. A strong, positive correlation between the number of species, Shannon’s diversity index, Simpson’s dominance index of soil seed bank and above-ground weed species was found in both farming systems, while abundance of seeds and above-ground weeds was significantly, positively correlated only in the conventional farming system. Qualitative composition of weed flora depended more on the type of community (soil seed bank or above-ground weed communities) than the farming system.
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