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Disturbance of the functionality in immunocompetent organs of chickens due to accumulation of cadmium
2018
Vasiljeva, S., University of Latvia, Riga (Latvia) | Basova, N., University of Latvia, Riga (Latvia) | Smirnova, G., University of Latvia, Riga (Latvia)
The high toxicity, bioaccumulative and increased distribution of cadmium (Cd) in the environment, makes it the most dangerous to any biological system, including immune system in human and animals. The effect of dietary intake of Cd (8.25 mg per kg) on accumulation and distribution of this heavy metal in various tissues, and functional changes in organs of immunity (thymus, bursa of Fabricius, spleen) in 35-day-old broiler cockerels were investigated, using biochemical and immunological methods. Significant increases in the Cd concentration both in central immunocompetent organs (thymus, bursa of Fabricius) and peripheral (spleen) were established. Excessive tissue level of Cd induced the prooxidative effect of this heavy metal in the organs. It was manifested in an increase of cell membrane lipid peroxidation (the enhanced malondialdehyde (MDA) concentration) in immune system organs. The oxidative stress resulted in immunocompetent cell damage. The fall of vital dye absorptive ability of immunocyte indicated the increase in the injured cell number. This harmful effect is in accordance with T- and B (C3) – population prominent depletion, organ relative mass reduction, and growth retardation in chicks, and was established as a result of dietary Cd loading for 5 weeks of the experiment.
Mostrar más [+] Menos [-]High pressure effect on the sensory and physical attributes of pork
2018
Sazonova, S., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Galoburda, R., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia)) | Gramatina, I., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Straumite, E., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia)
High-pressure processing (HPP) is typically used for the microorganism inactivation, which provides safety and prolonged shelf life of meat and meat products. However, for consumers along with safety, it is important to have good sensory properties, which is a combination of tender and juicy meat with an intense meat flavour. These attributes may change because of the high pressure processing; therefore, the aim of the study was to evaluate the effect of HPP on sensory and physical attributes of pork upon processing at 300 and 600 MPa at room temperature for 1 and 15 min. After HPP the processed pork samples were cooked within the package in a water bath. Colour of cooked pork did not differ among samples. Moisture content of samples decreased with the increased processing time. Sensory evaluation revealed that HPP treatment did not influence the colour and flavour of cooked pork irrespective of treatment parameters applied in the current study. The panellists indicated that increased pressure made pork samples drier and tougher, thus changing such sensory attributes as juiciness and chewiness, which are important for meat palatability. The correlation found between chewiness determined by sensory analysis and toughness determined by Warner-Bratzler shear device suggested this instrumental method as a better tool when compared to the instrumental texture profile analysis (TPA).
Mostrar más [+] Menos [-]Rye and oat crispbread improvement with biologically active substances from plant by-products
2018
Konrade, D., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Klava, D., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia)
Vegetable processing in food industry results in significant number of by-products – peel, mark, bark, seeds still rich in bioactive compounds. The objective of this study was to investigate the stability of total phenolic content (TPC) and antioxidant activity after high temperature short time (HTST) extrusion cooking of a rye and oat- based matrix with addition of apple, carrot and pumpkin by-product flour (BPF) in various amounts (5%, 10%, 15% and 20%). Extrusion was performed with co-rotating twin-screw extruder (compression ratio 8:1) at Ltd MILZU. The main drive of extruder was provided with a 7.5 HP motor (400 V, 3 HP, 50 cycles). Temperatures for extrusion zones were 125 °C /135 °C /145 °C. TPC was determined using the Folin Ciocalteu method. Antioxidant activity was evaluated by free radical 2, 2-diphenyl-1-picrylhydrazyl (DPPH) antioxidant scavenging activity. TPC in cereal-based crispbread was 62.03 ± 0.15 mg GAE gE-1 DW before extrusion and 37.73 ± 1.96 mg GAE gE-1 DW after extrusion. Addition 20% of apple BPF increased TPC in crispbread to 193.92 ± 1.37, carrot BPF 171.36 ± 6.97 and pumpkin BPF to 195.09 ± 4.68 mg GAE gE-1 DW after extrusion. Antioxidant activity of control (20% oats, 80% rye flour blends) sample was 0.516 ± 0.192 mg TE gE-1 DW but in samples with addition of 20% by-products, it was significantly higher reaching 0.926 ± 0.05 TE gE-1 DW in samples with pumpkin by-products after extrusion.
Mostrar más [+] Menos [-]Characterization of yellow rust (Puccinia striiformis Westend.): review
2018
Feodorova-Fedotova, L., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia);Latvian Plant Protection Research Centre, Riga (Latvia) | Bankina, B., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia)
Yellow rust caused by Puccinia striiformis is a significant wheat disease in cereal growing areas worldwide. On average, yellow rust can cause 50% big yield damages resulting in economic losses. Yellow rust damages wheat leaves, leaf sheaths, awns, and glumes. Puccinia striiformis is divided into four lineages – P. striiformis sensu stricto, P. pseudostriiformis, P. striiformoides, P. gansensis. Different races of yellow rust have been determined. After 2000 three new aggressive races – ‘Warrior’, ‘Kranich’ and ‘Triticale aggressive’ have been identified. New races are characterized by shorter latent period, extended spore germination and tolerance to a high temperature in comparison with the races determined before 2000. These characteristics allowed the new races to replace races dominant before 2000. Yellow rust is a biotrophic heteroecious fungus with a complicated life cycle. For successful development, Puccinia striiformis requires cereals as primary hosts and Berberis spp. as alternate hosts. The history of studies regarding yellow rust is more than two hundred years old but only in 2010 the ecidiospores of yellow rust were found on the alternate host Berberis spp. Two types of resistance – seedling (or all-stage) resistance and adult plant resistance (APR) were discovered. Since 2000 multiple severe epidemics of yellow rust have been observed in cereal growing areas with warmer climate. In recent years, the incidence of yellow rust in Latvia has increased. Particular studies about the biology, distribution, and races of Puccinia striiformis in Latvia are necessary. This article summarizes the information about the classification, biology and harmfulness of the yellow rust.
Mostrar más [+] Menos [-]Leaf optical properties reflect changes of photosynthetic indices in apple trees
2018
Lauzike, K., Lithuanian Research Centre for Agriculture and Forestry, Akademija, Kedainiai distr. (Lithuania) | Samuoliene, G., Lithuanian Research Centre for Agriculture and Forestry, Akademija, Kedainiai distr. (Lithuania);Aleksandras Stulginskis Univ., Akademija, Kauno reg. (Lithuania)
The impact of light penetration into crown and the effect of rootstocks and distance between trees on photosynthetic behaviour were analysed. Apple cultivar ‘Auksis’ was grafted onto dwarfing rootstock P60 and super-dwarfing rootstock P22 and planted at different distances (3 × 1 m, 3 × 0.75 m and 3 × 0.5 m). Nitrogen balance index and photochemical reflectance index were measured at two heights: 0.8 m above ground inside the canopy and 1.5 m above ground outside the canopy; specific leaf area, fresh and dry weight were evaluated from all canopy. The significantly positive effect of dwarfing rootstock P60 on all tested indices was observed comparing to P22 rootstock. Increasing density between trees lead to a decreased specific leaf area and increased nitrogen balance index. The dry and fresh weight ratio and photochemical reflectance index were also significantly affected, but no general tendency was identified. Photochemical reflectance index was not affected by light penetration into canopy, but the nitrogen balance index significantly decreased in the upper part of the canopy. Summarizing, it can be stated that decreasing light penetration into the crown results in an increase in the specific leaf area and photochemical reflectance index, and leads to a decrease in dry and fresh weight ratio and nitrogen balance index.
Mostrar más [+] Menos [-]Effects of different fertilizer treatments on grain yield and yield components of spring wheat
2018
Mikos-Szymanska, M., New Chemical Syntheses Inst., Pulawy (Poland) | Borowik, M., New Chemical Syntheses Inst., Pulawy (Poland) | Wyzinska, M., Institute of Soil Science and Plant Cultivation – State Research Inst., Pulawy (Poland) | Rusek, P., Institute of Soil Science and Plant Cultivation – State Research Inst., Pulawy (Poland)
The present research was carried out to investigate the effects of different fertilizer treatments on grain yield and yield components of spring wheat (Triticum aestivum L.) ‘Harenda’ cultivar. The five treatments were as follows: control (standard NPK fertilization), standard NPK fertilization plus liquid NPK (10-11-11) fertilizer, standard NPK fertilization plus liquid NPK (10-11-11) fertilizer with microelements, standard NPK fertilization plus calcium micronized suspension fertilizer, and standard NPK fertilization plus Cu, Mn, Zn, Ca micronized suspension fertilizers. The field trials were conducted in 2017 at the Experimental Site of Institute of Soil Science and Plant Cultivation – State Research Institute in Puławy, Poland. Applications of calcium micronized suspension foliar fertilizer and a mixture of Cu, Mn, Zn, Ca micronized suspension fertilizers significantly increased grain yield of spring wheat, respectively by 44.5% and 38.6% in comparison with control (standard NPK fertilization). These fertilizer treatments also enhanced yield components of spring wheat. Moreover, micronized suspension fertilizers (Ca and the mixture of Cu, Mn, Zn, Ca) had a significant effect on ear number and thousand grain weight of spring wheat compared to control and NPK fertilizers. Liquid NPK and micronutrient-enriched NPK fertilizers had a significant effect on thousand grain weight compared to control.
Mostrar más [+] Menos [-]Analysis of measurements of Latvian warmblood and Latvian heavy warmblood sires
2018
Veidemane, A., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Jonkus, D., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia)
The objective of the study was to analyze measurements of the sires used in Latvian Warmblood (LWB) and Latvian Heavy Warmblood (LHWB) breeding programs in the period 2003 – 2017, two major horse populations in Latvia included in one studbook. The Latvian Warmblood has an open studbook for breeding sport horses, whereas the Latvian Heavy Warmblood is a partly closed studbook. Measuring information for all sires with at least one foal born (n=834) in the respective time period was retrieved from the Latvian horse database, with 673 stallions measured at least once. The data consisted of direct measurements – height at withers, chest circumference and cannon bone circumference – and two calculated indices – massivity index and boniness index. Average values of adult stallions were analyzed in four groups – LWB, LHWB, ‘other warmbloods’ and refining breeds, with LWB and ‘other warmbloods’ showing similar average values. Sires were divided by use in breeding into 3-year periods to observe a possible change in the breeding objective and stallion choice, however, no significant differences were found in LWB or LHWB. Average measurements of stallions used in the LWB breeding program (different breeds) were 168.6 ± 4.3 cm for height at withers, 194.4 ± 6.6 cm for chest circumference, 21.8 ± 1.0 cm for cannon bone circumference, massivity index 115.5 ± 3.1, boniness index 13.0 ± 0.5. Average measurements of stallions used in the LHWB breeding program (only LHWB stallions) were 167.6 ± 4.6 cm, 201.4 ± 7.3 cm, 23.7 ± 1.0 cm, respectively, and massivity index 120.0 ± 5.0, boniness index 14.1 ± 0.6. Significant differences between LWB and LHWB stallions were observed in all parameters, except height at withers, and between measurements at the age of 2, 3, 4 years and adult (5 and more years).
Mostrar más [+] Menos [-]Projecting productivity in agriculture in Latvia
2018
Nipers, A., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Krievina, A., Latvia Univ. of Life Sciences and Technologies, Priekuli, Priekuli parish, Priekuli Municipality (Latvia). Inst. of Agricultural Resources and Economics | Pilvere, I., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia)
The development of rural territories in the European Union (EU) plays an essential role, and agricultural development can largely contribute to this process. To project agricultural trends, a number of models have been developed in the EU, while in Latvia the LASAM model was developed in 2016 to generate projections for agricultural sector development in Latvia until 2050. In 2017, LASAM was extended by a module for socio-economic assessment that allows projecting productivity for various types of farming. The research aim is to develop a model for productivity simulation for various specialisation types of farms in order to project their development in Latvia. To achieve the aim, two specific research tasks were set: 1) to develop a model for productivity simulation for various specialisation types of farms in Latvia; 2) to identify the key results of the simulation of productivity for various specialisation types of farms in Latvia. The research found that in the period 2005 – 2016 the value added of agriculture tended to slightly increase in Latvia, whereas an opposite trend was observed for the number of persons employed in agriculture, which tended to decrease in the period of analysis. Both trends determine the agricultural productivity trend as well. A projection of productivity measured as value added per AWU for various farming types in Latvia by means of the LASAM model has revealed that it is different, and the highest level of productivity in 2030 and 2050 is projected for granivores as well as field crop farms.
Mostrar más [+] Menos [-]Theoretical models of social enterprises in Latvia
2018
Licite, L., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia)
Social entrepreneurship plays an increasingly important role in tackling socio-economic problems. It has gained recognition in Latvia among politicians, academicians and social entrepreneurs; consequently, the number of social enterprises increased in the country, yet there is a lack of research studies on social enterprise models and their classification. Accordingly, the research aim is to examine the theoretical models of social enterprises in Latvia. In the scientific literature, there is no strict classification of social enterprises, but based on different criteria, it is possible to distinguish several types or models. In Latvia, there are relatively few social enterprises; for this reason, it is quite difficult to categorise them. However, social enterprises are divided by sector, field of activity, target group, scale of activity and other criteria. The research stresses the following key social entrepreneurship models: the Selfinitiative Model, the Government Participation Model, the Municipal Participation Model and the Company-initiated Development Model. These models are based on two key criteria – support intensity and taking the initiative in establishing and developing a social enterprise.
Mostrar más [+] Menos [-]Emplacement of creative IT specialists in Latvia
2018
Gribanova, S., Turiba Univ., Riga (Latvia) | Abeltina, A., Turiba Univ., Riga (Latvia)
Current paper contains the research concerning the role and concentration of IT specialists in contemporary Latvia. It is based on theoretical findings about the location of creative class in certain areas that meet the requirements of technology, tolerance and talent. At the same time, the advantages of creative people staying in the area are undoubted. Creative class and, first of all, super-creative core of creative class bring economic and technological development into the area it is located at. The goal of the article is to examine areas of creative IT specialist concentration within Latvia. The statistics and dynamics of IT position increase were examined and trends found. In order to define the role of IT specialists in Latvia, the allocations of IT specialists across the country were analysed. Herfindahl-Hirschman Index of Information and communication industry employee concentration was calculated. It was found that IT specialists in Latvia are extremely concentrated. Riga planning region accumulates 91.51% of all IT specialists in Latvia.
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