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The chemical composition and nutritional value of fish meat while using as a feed additive zeolite of Chankanay origin 全文
2013
Paritova, A., Kazakh National Agrarian Univ., Almaty (Kazakhstan) | Biltebayevna, N., Kazakh National Agrarian Univ., Almaty (Kazakhstan) | Kuzembekova, G., Kazakh National Agrarian Univ., Almaty (Kazakhstan) | Valieva, Z., Kazakh National Agrarian Univ., Almaty (Kazakhstan) | Sarybaeva, D., Kazakh National Agrarian Univ., Almaty (Kazakhstan
This article presents the results of studies of the chemical composition of the fish meat while using as a feed additive zeolite of Chankanay origin. The research was conducted during 2011-2013 at the Department of Veterinary-sanitary examination and hygiene of the Kazakh National Agrarian University and at the laboratory of JSC ‘Kazakh Academy of Nutrition’ LTD ‘NUTRITEST’. The material of study was the zeolitic tuff of Chankanay deposit (Almaty region) and two-year trout Oncorhynchus mykiss. For the research we used feed by recipes of GosNIORH - 12-80. The chemical composition of fish meat was determined by a set of methods: moisture by drying at 105 °C, fats by Soxhlet, total protein by modified Kjeldahl method (ISO 937:1974), and minerals by incineration in a muffle furnace. Calorie content of meat was determined by Alexandrov’s formula: X = C - (F+A) ´ 4.1 + F ´ 9.3. Fatty acid composition of fish meat was determined by gas-liquid chromatography. Thus, the results are the indirect evidence that zeolites added to primary diet for growing fish, do not adversely impact proteolytic enzyme systems of fish, that is, have no negative effect on fish organism.
显示更多 [+] 显示较少 [-]Calcium and phosphorus content in Roman snail (Helix pomatia) meat and shell 全文
2013
Ikauniece, D., Latvia Univ. of Agriculture, Jelgava (Latvia) | Jemeljanovs, A., Latvia Univ. of Agriculture, Jelgava (Latvia)
The aim of the study was to determine and compare calcium and phosphorus content in pedal mass, visceral mass and shell of wild and bred trial groups’ snails (Helix pomatia). The trial was performed from May to September of 2011 at the Roman Snail Research Facility of the Research Institute of Biotechnology and Veterinary Medicine „Sigra”, of Latvia University of Agriculture (LLU). Snails were divided in 4 trial groups depending on the diets. Samples were collected from the local natural population of snails and experimental breeding farm in spring (May), summer (July) and autumn (September). Significant differences (p is less than 0.05) were found between the levels of the calcium and phosphorus content in the edible part (pedal mass) and visceral mass in wild snails and experimental trial groups.
显示更多 [+] 显示较少 [-]Morphometric and masometric parameters of the ostrich (Struthio camelus) stomach in postnatal ontogenesis 全文
2013
Mancevica, L., Latvia Univ. of Agriculture, Jelgava (Latvia) | Mugurevics, A., Latvia Univ. of Agriculture, Jelgava (Latvia)
Stomach, as a part of the digestive canal, is important in the metabolic processes of the organism which affects the bird’s general health condition, its growth and development, consequently also the increase of the body weight. The aim of the research was to find out the dynamics of weight, length, and area of the ostrich (Struthio camelus) stomach and its parts in postnatal ontogenesis from 4 to 12 months of age. The absolute weight of stomach, length of the greater curvature of the stomach glandular part, diameter of the muscular part, thickness of stomach wall was determined. To find out the differences of the mean values between various age groups, ANOVA and Post Hoch tests were used. The increase of the stomach absolute weight continued throughout the postnatal ontogenesis period, but the stomach weight in relation to the ostrich body weight decreased, especially rapidly at the age of 6 and 8 months. At the same time, proportions of the absolute and relative weight of the stomach glandular and muscular part changed. The length of the greater curvature of the stomach glandular part, length of the deep gland region and diameter of the stomach muscular part increased during the whole observed period of ontogenesis; moreover, these parameters increased more rapidly from 6 to 8 months of age. The area of the stomach glandular and muscular part mucosa increased throughout the observed period of ontogenesis. The area of the superficial gland region in all age groups was larger than the area of the deep gland region.
显示更多 [+] 显示较少 [-]Review about investigations of Salix spp. in Europe 全文
2013
Pucka, I., Latvia Univ. of Agriculture, Jelgava (Latvia) | Lazdina, D., Latvian State Forest Research Inst. Silava, Salaspils (Latvia)
Willow species are nowadays extensively studied. Species are being investigated to evaluate their use and role in various sectors of national economy. The use of willows in short rotation coppice (SRC) for biomass and energy production has a priority in the European Union policy. There are many countries that have grants and financial aid system for so-called ‘green energy’ production. Willow species also have other economically and ecologically important features: resistance to contaminants, strong root system, high tannin contents, decorative, etc. Willow SRC systems are used for phytoremediation and in wastewater purification, in combination with biomass production. There are several countries of Eastern Europe researching adequacy of the willow SRC for the farmland contaminated by radionuclides segregated from the Chernobyl nuclear power plant disaster. Willows are used for quarry restoration, water sludge treatment, erosion control etc, but the most important field at the moment is the biomass production.
显示更多 [+] 显示较少 [-]The influence of the growing season on the spectral reflectance properties of forest tree species 全文
2013
Masaitis, G., Aleksandras Stulginskis Univ., Akademija, Kauno reg. (Lithuania) | Mozgeris, G., Aleksandras Stulginskis Univ., Akademija, Kauno reg. (Lithuania)
The aim of current study was to investigate the spectral separability trends of different tree species due to varying foliage spectral reflectance properties during the growing season. Five tree species prevailing in Lithuania were chosen for the study: aspen (Populus Tremula L.), black alder (Alnus Glutinosa (L.) Gaertn.), Norway spruce (Picea Abies L.), Scots pine (Pinus Sylvestris L.) and silver birch (Betula Pendula Roth). The hyperspectral reflectance data was collected under laboratory conditions scanning the foliage samples from two healthy middle aged stands. Hyperspectral scanning was implemented using Themis Vision Systems LLC VNIR 400H hyperspectral imaging camera in 400-1000 nm range. Principal component analysis and the Jeffries-Matusita distance measure were applied for the analysis of hyperspectral data. The wavelengths providing the best separability between tree species were determined. They were discovered to vary during the growing season: in late spring – early summer the most informative wavelengths were concentrated in blue and near infrared spectral zones, in summer they shifted towards green and red zones, and in autumn they moved further to longer waves - the red and near infrared - spectral zones. The investigated tree species were determined to be spectrally separable during the whole growing season, but the particular periods were revealed to contribute for improved spectral separability between certain tree species. The separability between coniferous species was best in September, while deciduous species were best separable when the samples were collected in August.
显示更多 [+] 显示较少 [-]Theoretical evaluation of wood for bioenergy resources in pre-commercial thinning in Latvia 全文
2013
Lazdins, A., Latvian State Forest Research Inst. Silava, Salaspils (Latvia) | Kaleja, S., Latvian State Forest Research Inst. Silava, Salaspils (Latvia) | Gruduls, K., Latvian State Forest Research Inst. Silava, Salaspils (Latvia) | Bardulis, A., Latvian State Forest Research Inst. Silava, Salaspils (Latvia)
The study represents results of theoretical evaluation of forest biomass available for solid biofuel production in pre-commercial thinning in Latvia. The study is based on the National forest inventory (NFI) data; calculations are done for each NFI plot separately. The calculation is done in three steps – selection of the NFI sample plots, which fulfils criteria for the pre-commercial thinning, development of the diameter distribution table, setting the criteria of the thinning intensity, calculation of extractable biomass. Thinning from below (removal of the smallest trees) is considered in calculation. Two types of biomass are accounted – full tree (aboveground biomass) and stem-wood (stem biomass). The study demonstrates that pre-commercial thinning could become an important source of forest biomass in Latvia (15400 GWh of primary energy according to current situation in forests); however, dimensions of trees and harvesting conditions might be challenging for production. The most of the potential biofuel resources are located in stands with average tree higher than 8 m; therefore, it is reasonably to develop and introduce technologies applicable for production of partially delimbed trees.
显示更多 [+] 显示较少 [-]Comparison of different electronic devices for detecting heterobasidion root rot 全文
2013
Gruduls, K., Latvia Univ. of Agriculture, Jelgava (Latvia);Latvian State Forest Research Inst. Silava, Salaspils (Latvia) | Donis, J., Latvian State Forest Research Inst. Silava, Salaspils (Latvia) | Gaitnieks, T., Latvian State Forest Research Inst. Silava, Salaspils (Latvia)
Root rot caused by Heterobasidion spp. is one of the most important pathogens in Norway spruce (Picea abies (L.) Karst.) stands in Latvia. It is estimated that in Latvia on average 22.9% of Norway spruce stumps are infected with Heterobasidion spp. The aim of this study was to compare four different electronic devices for Heterobasidion root rot detection in Norway spruce. In the autumn of 2009, in a sample plot located in the forests of Kalsnava district 27 trees were used to compare the possibility of instruments to detect root rot. The results show that IML-RESI F400 accuracy for detecting root rot in Norway spruce is high and the instrument is usable for detecting root rot, but additional accumulators are needed for large sample plots. Rotfinder’s accuracy for detecting root rot varies from probe to probe taken from one tree. Conditiometer AS-1 and Arbo-Sonic decay detector show slightly higher average values for infected trees, but the difference for both instruments between healthy and decayed trees is not significant, thus leaving the usage of instruments questionable.
显示更多 [+] 显示较少 [-]Economic value of wood chips prepared from young stand tending 全文
2013
Kaleja, S., Latvia Univ. of Agriculture, Jelgava (Latvia) | Grinfelds, A., Latvia Univ. of Agriculture, Jelgava (Latvia) | Lazdins, A., Latvian State Forest Research Inst. Silava, Salaspils (Latvia)
Small diameter wood obtained from young stand tending, with average d1.3 is greater than 4 cm, is suitable for the production of biofuel. So far mainly hand motorized tools have been used in young stand tending, to gather the small -diameter wood is costly and unprofitable. As the technology evolves and labor costs rise studies are carried out on how to increase the profitability of the young stand tending, by applying mechanized tending and production of biofuel from small-diameter wood. The study analyzed indicators, which directly affect the profitability of biofuel production from small-diameter wood produced by harvester tending. The biofuel production costs are analyzed using average purchase price of wood chips production service paid by JSC ‘Latvijas valsts meži’ (further JSC LVM). Revenue related to sales of chips is analyzed on the basis of JSC LVM average sales price for wood chips. The price of the preparation of the small-diameter wood is high and the proportions of the full cost price of wood chips make up 38%. The price of forwarding service impact on the full cost price comprises up to 25% and depends on the forwarding distance. The profitability calculation shows, that production of wood chips from the harvester tended young stands has to be regarded as unprofitable.
显示更多 [+] 显示较少 [-]Linear regression analysis of indices describing Latvian wood processing industry 全文
2013
Krumins, J., Latvia Univ. of Agriculture, Jelgava (Latvia) | Smits, I., Latvia Univ. of Agriculture, Jelgava (Latvia) | Dagis, S., Latvia Univ. of Agriculture, Jelgava (Latvia) | Dubrovskis, D., Latvia Univ. of Agriculture, Jelgava (Latvia) | Arhipova, I., Latvia Univ. of Agriculture, Jelgava (Latvia)
To forecast how different indices describing Latvian forest industry will develop in the future, the decision support program which is based on the research of supply chains and production processes as well as on systematic analysis of the whole industry should be developed. One of the most common types of analysis is modelling of processes. In this paper processes of forestry and wood processing in Latvia are modelled by using general approach for system modelling, and each process is described as an abstract system where only its input and output values were identified. Correlations of input and output value time series with a simple and multiple regression analysis method were analyzed. Regression analysis was created for 77 pairs of indices which theoretically could have significant correlations. Input and output factor linear regression analysis for set of processes Forestry and Wood processing shows that not always there is significant correlation between time series of chosen model factors. Some of correlations between time series of input and output data in the model of forest sector even showed controversial results. The amount of information about processes and their quantitative indicators in Latvian wood processing industry is not sufficient for development of precise simulation models. There is need to develop a list of criteria for missing information and carry out its collection process.
显示更多 [+] 显示较少 [-]Internal factors affecting competitiveness of Latvian small and medium-sized furniture manufacturers 全文
2013
Lise, S., Latvia Univ. of Agriculture, Jelgava (Latvia) | Marcins, J., Latvian Association of Wood Processing Entrepreneurs and Exporters, Riga (Latvia)
The furniture industry is an innovative industry that produces high added value products and its turnover is several billions of Euros in Europe, and there mainly work small and medium-sized enterprises (abbreviation – SMEs). Nowadays competitiveness is an essential factor for both a country and its enterprises in the process of dealing with changing market conditions. The global market is changing and for enterprises it is too hard to position themselves and find the way how to differ from other competitors. From 2006 until 2010 a Latvian furniture market value, numbers of employees and enterprises in the sector and its share in GDP has decreased. As a result, there are the serious challenges to be met and increase their competitiveness in domestic and export markets. The author has made an in-depth research into influencing competitiveness factors of SME micro level in the furniture manufacturing industry. The study objective was to identify the key internal factors which influence the SME of Latvian furniture manufacturers. The aim was to obtain an internal factor of competitiveness assessment of the 30 respondents by random sampling method and expert method of factor assessment. The enterprises need to constantly increase their competitiveness. The internal factors influencing the competitiveness of SMEs are connected with the products, manufacturing of products, financial situation, management and marketing activities. The competitiveness level of Latvia`s SMEs in the furniture manufacturing has been evaluated as average in 70% of cases. Only 27% of the enterprises show a good level of competitiveness.
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