خيارات البحث
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Constraints and prospects for apiculture research and development in Amhara region, Ethiopia
2009
Ejigu, K. | Gebey, T. | Preston, Thomas R.
Ethiopia has been amongst the principal honey and beeswax producers worldwide for centuries. Beekeeping in Amhara region could be one way of assisting millions of the region’s farmers to improve their cash income, provide additional food, assist in pollination, generate employment and at the same time produce honey, beeswax and other hive products which can bring foreign currency into the country. This paper discusses the constraints and the future prospects on apiculture development of the region. The challenges are many but can be overcome while the opportunities are very encouraging. As a conclusion, developing appropriate policy and beekeeping development strategy that would be applicable to the different production systems will ensure the sustainable development of apiculture sub sector.
اظهر المزيد [+] اقل [-]Reproductive performance of traditionally managed sheep in the south western part of Ethiopia
2009
Berhanu, Belay | Haile, Aynalem
The study was conducted to assess the reproductive performance of ewes under village management condition in south western part of Ethiopia. The study was a monitoring study which took place for three years (1995-1997). The overall least squares means for lambing interval (LI) and annual reproductive rate (ARR) were 262 ±53.4 days and 1.88 ± 0.44, respectively. The overall least squares means of age at first lambing and litter size were 404 + 65.40 day and 1.21+1.45 lambs, respectively. Lambing interval was significantly (P<0.05) influenced by parity of the ewe, type of birth and year of lambing. The ewes at their first, and six and above parity showed longer subsequent lambing interval than ewes at 2-5 parity. Ewes that suckled singles had shorter subsequent lambing interval than ewes which suckled twins (255+3.74 vs 283+5.72 days). Year of lambing and type of birth exerted a significant effect (P<0.05) on ARR. The ewes that dropped twins had higher ARR than ewes which dropped singles (1.52 Vs 2.56 lambs/ewe/year). Litter size was significantly (p<0.05) influenced by season of lambing and parity of the ewe. There was a tendency that, litter size increased with an increase of parity up to fifth parity and dropped at the sixth and more parities. The reproductive performance of ewes under village management condition is discussed in association with reports elsewhere in the tropics.
اظهر المزيد [+] اقل [-]Factors affecting growth performance of sheep under village management conditions in the south western part of Ethiopia
2009
Bela, B. | Haile, Aynalem
The study was conducted to assess the growth performance of lambs under village management condition in Jimma, Ethiopia from 1995 to 1997. The overall mean body weight at birth, at weaning (180 days) and up to a year (360 days) was recorded to be 2.45, 18.8 and 25.4 kg, respectively. The overall mean growth rate up to weaning weight (180 days) and up to one year old (360 days) was 92.3 and 68.3 g/day. The non-genetic factors such as season, yea, sex, parity, litter size and district were considered in this study. The main factors had a significant effect (at least p<0.05) on weight for age and weight gains recorded. A consistent significant effect of sex and birth type (single/twin) (p< 0.05) was observed for weight for age and growth rates. The males were heavier than females, by 7.11% and 10.2 % for 180 days and 360 days weight, respectively. The twins were lighter than singles by 20.1 % and 8.32% for 180 days and 300 days weight, respectively. The effect of parity was significant (p<0.05). The lambs born to ewes at first parity had lower weight for ages and weight gains compared to subsequent parities. The lambs born in land scarce area (Dedo district) had lower weight gains than lambs born in Seka (land better area). Differences were significant (P<0.05) and weight gain recorded at 180 days were 85.3 and 90.9 g/day for Dedo and Seka lambs, respectively. The variation in growth performance of sheep in different districts could provide base line information to set a long-term genetic improvement plan by election. The results are discussed in comparison with data obtained from elsewhere in the tropics.
اظهر المزيد [+] اقل [-]Handling, processing and marketing of milk in the North western Ethiopian highlands
2009
Alemayehu, Y.A. | Wurzinger, Maria | Tegegne, Azage | Zollitsch, W.
In order to describe the ways of handling, processing and marketing of milk in urban and peri-urban production systems of the North western Ethiopian highlands, 256 and 54 dairy farms were selected for survey and monitoring data collection, respectively. Due to poor market access and high transaction costs and the perishable nature of raw milk, the amount of sold milk (products) and prices were significantly lower for peri-urban producers. Prices were also low during fasting periods and during the wet season; when milk production was reactively high. Traditional ways of milk processing at household level include practices which may contain risks for product quality affecting consumers’ health. Providing basic handling and health education for producers therefore is likely to result in improved milk (product) quality on the markets. Direct delivery to the nearby consumers was the largest primary milk outlet for producers of both systems, while retailers and milk cooperatives were the second most common outlets for the urban and the peri-urban system, respectively. Therefore, to enhance dairy production and marketing, milk co-operatives that could be able to market larger volumes and sufficiently reduce transaction costs should be supported by governmental and non-governmental organisations through providing technical and infrastructural support.
اظهر المزيد [+] اقل [-]Characteristic of grain quality for early generation lines in the crossings between covered and hull-less barley
2009
Bleidere, M., State Stende Inst. of Cereal Breeding, Dizstende, Talsu reg. (Latvia) | Belicka, I., State Stende Inst. of Cereal Breeding, Dizstende, Talsu reg. (Latvia)
The objectives of the investigation were to determine effect of hull-less gene on grain quality traits (crude protein, starch and β-glucans) and to evaluate the heritability of these traits in the F4 and F5 generations of six crosses between covered and hull-less barley (Hordeum vulgare L.). The trial was carried out at the State Stende Cereal Breeding Institute during the years 2007 and 2008. Mean value, range and the coefficient of variation of traits for covered and hull-less lines within each cross combination were calculated. Heritability of quality traits was estimated as intergeneration correlation (r) and linear regression coefficients (b). The highest intergeneration correlation values were observed for starch content within covered and hull-less barley populations (rF4:F5=0.609 and 0.635 respectively). Moderate intergeneration relationship was observed for crude protein content within covered barley population (r=0.582), and for β-glucans content within hull-less barley population (r=0.593). The regression estimates of heritability were higher for starch content for both covered and hull-less barleys (b=0.549 and 0.703 respectively). Due to effects of genotype and environment interactions the regression estimates of heritability for crude protein and β-glucans content for both covered and hull-less barley were low (b varied from 0.347 to 0.373).
اظهر المزيد [+] اقل [-]Effects of growing location and variety on free tryptophan and mineral nutrient content in wheat
2009
Lundegaardh, B., Swedish Univ. of Agricultural Sciences, Upsala (Sweden). Centre for Sustainable Agriculture | Jastrebova, J., Swedish Univ. of Agricultural Sciences, Upsala (Sweden). Dept. of Food Science | Zhokhov, S., Swedish University of Agricultural Sciences, Upsala (Sweden). Dept. of Chemistry | Maartensson, A., Swedish Univ. of Agricultural Sciences, Upsala (Sweden). Dept. of Soil and Environment | Oeborn, I., Swedish Univ. of Agricultural Sciences, Upsala (Sweden). Dept. of Plant Production Ecology
Tryptophan (Trp) is an essential amino acid for mammals since they cannot synthesise it. Wheat (Triticum aestivum L.) is a major source of dietary Trp, and wheat high in Trp would thus be very beneficial. This study investigated the impact of location and wheat variety on the content of free Trp and mineral nutrients in wheat grain. Four wheat cultivars from national variety tests on wheat with varying protein contents were selected from seven different locations of Sweden representing different climatic zones and soil contents of trace elements. Grain was analysed for Trp content using reversed phase HPLC. Mineral nutrients were analysed using inductively coupled plasma emission spectrometry. Wheat yield and grain content of nutrients and Trp differed significantly between sites. High N content in grain was correlated with a high content of Cu, Fe and S, and also Ca and Mg. However, it was correlated with a low content of K and Na. Trp content was positively correlated with Na and Zn content and negatively correlated with K/Na and K/(Na+Zn) ratio. The varieties differed in Trp content and the two ratios, but there were no significant differences in yields between the varieties at any location. The results indicated salt stress induction of Trp synthesis, which may protect wheat against salt stress and yield losses.
اظهر المزيد [+] اقل [-][Factors that influence the starch content in winter rye]
2009
Poisa, L., Latvia Univ. of Agriculture, Jelgava (Latvia);Agricultural Science Centre of Latgale, Vilani, Rezekne reg. (Latvia)
The EU Directive on the promotion of the use of biofuels or other renewable fuels for transport (CO M 2003/30/EC) states that the proportion of biofuels in 2010 must make 5.75% of non-renewable fuels, but in 2020 - 10%. The only way for Latvia to fulfil the Directive 2003/30/EC is to use winter rye because it is one of the oldest cereals grown in Latvia, and Latvia has a long-lasting experience in growing it. A field trial of winter rye (Secale cereale L.) was arranged in the Agricultural Science Centre of Latgale from 2005 to 2007. The influence of four winter rye varieties and five fertilizer rates on grain yield and starch content was researched for three years. The year (factor A), the varieties (factor B), the fertilizer rates (factor C), and the interaction of factors AB, AC , BC, and ABC significantly influenced the yield of grain and the starch content with 95% probability. It is recommended to use good quality grain with high starch content and low protein content for bioethanol production. The varieties of winter rye 'Kaupo', 'Amilo', and 'Walet' are the most suitable for ethanol production in Latgale region.
اظهر المزيد [+] اقل [-]Development of driving cycles for dynamometer control software corresponding to peculiarities of Latvia
2009
Dukulis, I., Latvia Univ. of Agriculture, Jelgava (Latvia) | Pirs, V., Latvia Univ. of Agriculture, Jelgava (Latvia)
Performing biofuel use studies, a large number of parameters that characterize engine operation under different conditions and with different fuel mixtures have to be identified. The real driving conditions are usually simulated by driving cycles on a laboratory chassis dynamometer. There are two major categories of driving cycles: legislative and non-legislative. From the viewpoint of cycle formation there are also two ways. One is composed of various driving modes of constant acceleration, deceleration and speed, and is referred to as modal or polygonal. The other type is derived from actual driving data and is called as 'real world' cycle. There is a strong agreement among researchers that driving characteristics of each city are unique because of different vehicle fleet composition, driving behaviour and road network topography. It is therefore better to develop own driving cycles than using driving cycles developed elsewhere. The aim of this investigation is to develop driving cycles or models for dynamometer control software corresponding to peculiarities of Latvia. The procedure for cycle development and fuel consumption and exhaust emissions measurement was worked out. Using real driving data on the Jelgava streets, models simulating driving in different urban areas were constructed. The model quality was determined using vehicle driving parameters and fuel consumption measurement results from both the road and laboratory tests. Since the obtained data coincidence of all the parameters exceeded 98%, the elaborated cycles can be used for the biofuel use efficiency determination.
اظهر المزيد [+] اقل [-]Methodology of dietary fibre determination in grain products
2009
Ozolina, V., Latvia Univ. of Agriculture, Jelgava (Latvia) | Gramatina, I., Latvia Univ. of Agriculture, Jelgava (Latvia) | Kunkulberga, D., Latvia Univ. of Agriculture, Jelgava (Latvia)
The dietary fibre is edible parts of plants' carbohydrates that are resistant to digestion in human small intestine. Diets naturally rich in dietary fibre support to prevent constipation, improve gastrointestinal health, glucose tolerance and the insulin response, and reduce the risk of colon cancer, hyperlipidemia, hypertension and other coronary heart disease risk factors. About 45% of the dietary fibre intake comes from grains and grain mixtures. In Latvia, there are neither data, nor investigations of the dietary fibre content in grain products during processing and in the end products in which manufacturers and consumers are interested. The aim of this paper was an approval of dietary fibre determination methodology by using analytical equipment the Full option science system (FOS) Analytical Fibertec E 1023. The dietary fibre determination experiments were carried out in the Research Laboratory of the Department of Food Technology at the Latvia University of Agriculture in 2009. The Total Dietary Fibre (TDF) content was analyzed in the samples of rye whole grain flour, rye whole grain bread, and wheat biscuit. Experiments showed that the fibre content in rye whole grain flour is 13.8 g 100 gE-1, in rye whole grain bread - 11.6 g 100 gE-1, and in the wheat biscuit - 1.9 g 100 gE-1. Reached data are comparable with results of other researchers' data.
اظهر المزيد [+] اقل [-]Inhibition of microbial growth of a salad with meat in mayonnaise by different packaging technologies
2009
Levkane, V., Latvia Univ. of Agriculture, Jelgava (Latvia) | Muizniece-Brasava, S., Latvia Univ. of Agriculture, Jelgava (Latvia)
The objective of the research was the shelf life extension of a salad with meat in mayonnaise. The microbial stability of the salad with meat in mayonnaise packaged under vacuum, in modified atmosphere, and using 'Sous vide' technology was examined and compared with conventionally packaged (in ambient air) salad. The salads were packaged in polyamide/polyethylene pouches with barrier properties as well as in pouches made from biodegradable plasticized poly-β-hydroxybutyrate or polylactic acid film. Control samples without preservatives were packed in traditional polypropylene containers covered with non-hermetic lids. PURASA L Powder Opti Form (sodium lactate) in the amount 5 g kgE-1, 10 g kgE-1, and 15 g kgE-1, and ethyl alcohol in the amount of 2 ml were used as single preservatives for separate samples. The studies of the samples were carried out after 1, 3, 7, 10, 15, 18, 25, 29, 42, and 52 storage days at the temperature of +4+-0.5 deg C. Experimentally the quality of the salad with meat in mayonnaise was characterized by measuring the total plate count of microorganisms. The obtained results indicate that different packaging technologies and addition of preservatives show significantly different influence on the microbial growth in different samples. 'Sous vide' packaging technology was effective for the shelf life extending and guarantee of safety of the salads with meat in mayonnaise.
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