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Beef consumption trends in Latvia
2009
Popluga, D., Latvia Univ. of Agriculture, Jelgava (Latvia);Latvian State Inst. of Agrarian Economics, Riga (Latvia)
Over the last few years, the increase of society stratification and inequality of income that has favoured significant shifts in household dietary patterns and a growing demand for products of animal origin, particularly meat and milk can be observed. On the consumption side, meat plays an important role in improving the nutritional status of low-income households by addressing micro and macro nutrient deficiencies. In this context, this paper investigates beef consumption trends and aims to corroborate theoretical expectations with empirical findings. The aim of the research was to characterize main tendencies of beef consumption and to find out factors affecting beef consumption in Latvia. In order to achieve the set aim, the following research objectives were defined: 1) to characterize household expenditure for purchasing beef; 2) to describe overall beef consumption in Latvia; 3) to investigate beef consumption in households with different income level. The study was based on annual statistical data, statistical bulletins covering results of the Household Budget Survey from 2002 to 2007, scientific publications and special literature. To carry out the research, adequate research methods were used. The results of this study showed that beef consumption in the country has been more or less stable, although in relatively small amounts. The main factor that influences beef consumption and expenditure on beef is income level. The results also suggested that higher beef consumption is characteristic of urban households, which have higher income level than rural ones. Therefore, within increase of income level of Latvia's inhabitants, beef consumption and demand for beef could significantly increase.
Afficher plus [+] Moins [-]Impact of Angiriai Hydropower Station on the ecosystem of the River Šušvė
2009
Vaikasas, S., Lithuanian Univ. of Agriculture, Kaunas (Lithuania). Water Management Inst. | Palaima, K., Lithuanian Univ. of Agriculture, Kaunas (Lithuania). Water Management Inst.
After a 16-m high dam was constructed and a 297-ha pond was arranged in the River Šušvė nearby Angiriai in 1980, the previous natural flow regime of the river has changed: 15500000 m3 of water accumulated above the dam is not discharged via a natural bed, but through two 1.5x1.5 m bottom orifices, and flood discharges (up to Q1% = 296 m3 sE-1) are directed into the lower reach through a 16-m high shaft spillway of floods. Such arrangement of the Angiriai dam ensured it to become an essential obstacle for migrating fish. In 2000, after the arrangement and operation of Angiriai hydro-electric power station, the water regime downstream the dam has been changed and new hydrological pulses as well as ecosystem biodiversity are to be adapted. Thus, the operation of Angiriai HPS on the River Šušvė generating hydroelectric power can have adverse effect on the river habitats and hydro ecological connectivity. To evaluate the effect, the eco-hydraulic water regime measurements in 2005 in a lower stretch with and without turbines operating were made. The study results showed that artificial water levels fluctuation (≈ 4 m hrE-1) induced by Angiriai hydro-electric power station as well as the discharge flowing through the bottom orifices due to high velocities (13–14 m sE-1) and temperature differences could create stressful situations for young fish in the lower bank. According to the data of soil texture of the Šušvė River, the bed armoring process is going on below the Angiriai HPS is quasistable and no impact of HPS operation is found.
Afficher plus [+] Moins [-]Calculation method of rainfall flow rate
2009
Ziemelnieks, R., Latvia Univ. of Agriculture, Jelgava (Latvia) | Tilgalis, E., Latvia Univ. of Agriculture, Jelgava (Latvia)
The aim of this research is to work out the graphic method for the calculation of the maximum rain intensity with a different guarantee in Riga. In order to develop this method analysis as regards the rainfall rates having a different probability was carried out. The measurement data of maximum rainfall minute intensity (mm minE-1) 3 and 9 hours as well as daily common rainfall from the accessible archive materials in the period 1954-2006 have been studied in this research and treated with the mathematical statistics methods. After the data collection and calculations, the final results are shown in a graphical way in which it is easy to determine which guarantee percent and repetition probability the rain intensity in Riga may be foreseen. In order to determine which module of one factor regression is the most accurate, five different modules were investigated. From the modules studied the most adequate one for data analyses was the logarithmic module having the accuracy up to 92%. The analysis of the rainfall data as well as the research of the situation of the location place can help to choose the system of rain accumulation and infiltration for each building location thus improving the operation of the total sewerage system. The calculations may be useful in practice to calculate the runoff rates from the areas of different covering. If necessary, using the graphic, it is possible to work out a mathematical expression for the calculation of the maximum rain intensity having any necessary probability. The accessibility and application of a wide range of materials for modern surfaces or infiltration buildings in the world present a wider range of their practical use for separate modern solutions in Riga.
Afficher plus [+] Moins [-]Nitrate monitoring results in agricultural catchments
2009
Lagzdins, A., Latvia Univ. of Agriculture, Jelgava (Latvia) | Jansons, V., Latvia Univ. of Agriculture, Jelgava (Latvia)
The paper deals with monitoring results of nitrate nitrogen (NO3 --N) run-off in three small agricultural catchments in Latvia (Berze, Mellupite, and Vienziemite) during the period of 1995 - 2007. Continuous flow measurements and water sampling were carried out in two scales - catchment and drainage field. Water quality data was analyzed statistically to identify outliers at various intensity agricultural production systems. The results indicated that with increase of agriculture intensity outlying values are higher and scattered from the rest of the data set thereby the risk of NO3 --N leaching is higher. It can be explained by application of different rates of organic and inorganic fertilization. To analyze water discharge data, cumulative distribution was used. The results show that main part of the water discharge is observed from late autumn to spring, whereas in summer period it is low and stable. The dependence of NO3 --N concentrations on the discharge is expressed by Spearman's correlation coefficient - at catchment scale it is 0.37 in Vienziemite site, 0.39 - in Berze, and 0.44 in Mellupite. Calculated correlation coefficients are statistically reliable.
Afficher plus [+] Moins [-]Review of industrial communication networks in the control of small-scale autonomous power supply systems
2009
Osadcuks, V., Latvia Univ. of Agriculture, Jelgava (Latvia) | Galins, A., Latvia Univ. of Agriculture, Jelgava (Latvia)
This article gives a review of modern networking technologies and standards used in the development of distributed control systems. Study of related scientific and professional literature has been performed, and basing on it a multi-level model of digital network structure in the field of small-scale autonomous combined power systems has been proposed. Necessity of integration of autonomous powering into SmartHouse systems and related distributed computing and networking issues are reflected as well. As there is a wide variety of industrial networking standards used, this review covers and groups more frequently used protocols and stacks from the view of OSI (Open Systems Interconnection) reference model and layers of industrial automation. The aim of this article is to give a reference-point in the development of distributed control systems in the field of small-scale autonomous power supply and integration of them in SmartHouse systems.
Afficher plus [+] Moins [-]Teacher education: the focus on doctoral studies
2009
Luse, N., Riga Teacher Training and Educational Management Academy (Latvia)
The Bologna Process started in 1999, aiming to elaborate an overarching framework of qualifications for the European Higher Education Area. The doctoral level as the third cycle was introduced for promoting closer links between research and higher education. The implementation of doctoral programme of pedagogy has strengthened the area of educational research. The general goal of the doctoral education is to provide doctoral students with an in-depth knowledge of the field of research and the capability to produce novel scientific knowledge independently. The aim of the paper is to characterize the realisation of teachers' education as doctoral training in the context of Bologna Process strategies. The seminar in Salzburg set up ten basic principles concerning doctoral education. Learning outcomes in the field of research training are one of the basic building blocks of European higher education quality. The quality of teachers' education on doctoral studies level is depending on advanced learning outcomes of an individual. The goals of doctoral education are increasing internationalisation, co-operation between academies, promoting academic careers and establishing post-doctoral positions. The investigation about research training was carried out at Riga Teacher Training and Educational Management Academy doctoral study programme in pedagogy. A questionnaire about aspects of doctoral studies was developed for obtaining information for analysis and was given to teachers (doctoral students). Respondents were asked to complete the questionnaire focusing on learning outcomes. The estimation of the results was made summing the answers, and the percentage was calculated. Feedback from doctoral students plays an important role in the further development of the curricula.
Afficher plus [+] Moins [-]Benefits of adopting improved forages in smallholder farms in Central America: An ex post analysis
2009
Holmann, Federico J. | Argel M., Pedro J. | Pérez, E.
The objective of this study was to estimate the benefits received by producers who adopted improved forages as part of a project[1] carried out in Guatemala, Honduras, Nicaragua, and Costa Rica in terms of increased productivity, stocking rate, and income due to the additional sale of milk and beef in retribution for family labor. Data were obtained from a survey carried out in 2007 that included nine producers in Guatemala, 16 in Honduras, 16 in Nicaragua, and 15 in Costa Rica who had adopted different grass and legume options during the period 2003-2007. The area planted to improved pastures increased in all countries, ranging from 12% in Guatemala to 105% in Nicaragua. Except for Guatemala (where the animal inventory decreased almost 11% due to Hurricane Stan), all countries expanded their herds (between 34% and 41%) in practically all animal categories, not only adult cows. On-farm milk production during the dry season increased 9% in Guatemala, 47% in Honduras and Nicaragua, and 71% in Costa Rica. Milk production during the rainy season remained practically invariable in Guatemala, but increased 48% in Honduras, 19% in Nicaragua, and 53% in Costa Rica. On the other hand, these increases in milk production were also favored by the rise in milk prices in all countries, ranging from 7% in Nicaragua to 36% in Costa Rica during the dry season and from 4% in Nicaragua to 36% in Costa Rica during the rainy season. Beef production accordingly increased 15% in Nicaragua, 46% in Honduras, and 74% in Costa Rica. similar to the trend observed in milk production, beef production did not increase in Guatemala because producers had to sell animals to recover from the losses caused by Hurricane Stan. Likewise, at the end of the project, producers in all countries received higher prices as compared with those obtained at the beginning of the project. The price of beef paid to the producer increased 9% in Guatemala, 4% in Honduras, 5% in Nicaragua, and 11% in Costa Rica. Because of these significant increases in annual milk and meat production, major increases were also observed in the annual net income of farms, reaching 32% in Guatemala, 288% in Honduras, 177% in Nicaragua, and 238% in Costa Rica. These extraordinary increases in net income can be attributed to three factors: (1) the higher milk price in 2007 as compared with that of 2003; (2) higher production due to the better diet; and (3) increased production due to the higher stocking rate allowed because of the adoption of and increase in area sown to improved forages. The increase in the net income of these producers has triggered an increase in the economic returns to family labor, as compared with the commercial value of a day’s wages. Therefore, the returns to family labor in Guatemala went from 3.1 times the value of the minimum wage in 2003 to 6.0 times that value in 2007, representing a 97% increase. In Honduras, the returns to family labor went from 2.9 times the minimum wage in 2003 to 9.8 times that value in 2007, representing a 238% increase. Similarly, in Nicaragua these returns represented a 104% increase and in Costa Rica a 200% increase.
Afficher plus [+] Moins [-]Genetic diversity and relationship of indigenous goats of Sub-saharan Africa using microsatellite DNA markers
2009
Muema, E.K. | Wakhungu, Judi W. | Hanotte, Olivier H. | Han Jianlin
Sub-Saharan African goats with an estimated population of 180 millions are major asset for farmer communities in a range of agro-ecological zones. This study was undertaken to determine the genetic diversity in and differentiation of relationships among 18 populations of goats from Uganda (4), Tanzania (5), Kenya (2), Mozambique (2), Nigeria (3), Mali (1) and Guinea Bissau (1). Heterozygosity, estimates of FST, genetic diversity and distances were performed using data from 11 microsatellite DNA loci. Expected heterozygosity ranged from 0.450 in Guinea Bissau population to 0.541 in Mbeya population (Tanzania), while the observed heterozygosity ranged from 0.441 in Pafuri population (Mozambique) to 0.560 in Sebei population (Uganda). Mean number of alleles (MNA) per population ranged from 3.82 to 5.91. Gene differentiation (FST) among populations was low (5.3%), a result confirmed by genetic distances (DA). Our results reveal that genetic relationships between populations reflect their geographical proximity rather than morphological classification.
Afficher plus [+] Moins [-]Factors influencing the prevalence of trypanosomosis in Orma Boran (trypanotolerant) and Teso zebu (trypanosusceptible) cattle crosses in Teso District, western Kenya
2009
Gachohi, John M. | Bett, Bernard K. | Murilla, G.A.
The objective of this study was to determine factors associated with occurrence of trypanosomosis in the first generation (F1) crossbreds between trypanotolerant Orma Boran and trypanosusceptible Teso zebu cattle in a trypanosomosis endemic area in Teso District, western Kenya. The offspring were screened for trypanosomosis and other haemoparasites using parasitological methods. Packed cell volume (PCV), body weights and tsetse density (FTD) were also determined. Factors considered in the analysis included sex, age, body weight and season of the year. Generalized linear mixed models (GLMM) were used for multivariable analysis to account for clustering of observations at the animal level and estimate outcome variance parameters. The overall trypanosomosis prevalence was 2.3% (n=477) probably corresponding to low FTD in the area (<1fly/trap/day). The risk of trypanosomosis infection was higher in dry than wet season (OR = 5.4) and in older than younger offspring (OR = 1.1). The variance parameters obtained indicated that variation of trypanosomosis prevalence lay only at the animal level. Intercurrent haemoparasites detected included Anaplasma marginale, Theileria and Babesia species. Overall, the results suggested that when the tsetse density is very low, control of trypanosomosis in the Orma-Teso zebu offspring in western Kenya require targeting of individual affected animals in the dry seasons.
Afficher plus [+] Moins [-]Modelling of long term pasture production and estimation of carrying capacity of Ankole pastoral production system in South Western Uganda
2009
Mulindwa, H. | Galukande, E. | Wurzinger, Maria | Okeyo Mwai, Ally | Sölkner, Johann
The Ankole pastoral production system in South Western Uganda is based on grazing without supplementary feeding. A stochastic simulation model was developed to determine the dynamics of pastures grazed by Ankole cattle and their Holstein Friesian crosses and the carrying capacity (CC) of the livestock grazing system. The model used the concept of rain use efficiency which relates pasture production to rainfall. A cross sectional study was carried out on 16 selected farms and data on number of animals, sex, age group and size of available grazing land was collected. The similarity between the results of the simulation rainfall runs and field data are considered to be satisfactory. The overall annual forage production is 3905 ± 72kg/ha. The lowest CC (5.65 ± 0.75) occurs in long dry season (June to August) while the highest CC (1.41 ± 0.06 ha/TLU) occurs in short rain season (September to November). Annual carrying capacity ranges between 1.88 and 2.08 ha/TLU with an overall mean of 1.95 ± 0.04 ha/TLU. Sixty three (63%) percent of the surveyed farms have stocking rates that are higher than the CC throughout the year while the rest are overstocked in the dry seasons of the year. The results indicate that CC is dynamic and its variability is more pronounced within the year than between years. In response to seasonal CC, the major point of intervention in regard to reduction of actual stocking rates could be done in May shortly before the start of the long dry season. For Ankole pastoral system to be sustainable, the stocking rate should not go below 1.41 ha/TLU.
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