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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.
Mostrar más [+] Menos [-]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.
Mostrar más [+] Menos [-]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.
Mostrar más [+] Menos [-]Influence of agroecological factors on winter oilseed rape (Brassica napus L.) autumn growth
2009
Balodis, O., Latvia Univ. of Agriculture, Jelgava (Latvia)
Sowing area under oil-seed rape (Brassica napus L.) has increased during last decade in Latvia and has become more or less stable since 2007. Lack of research on impact of sowing date, sowing rate, fungicide as growth regulator application and other agroecological factor issues on rape autumn growth is observed. The aim of our research, started in autumn 2007 in Research and Study farm Vecauce, was to investigate the influence of applied agroecological factors (five sowing dates, four sowing rates and fungicide (as growth regulator in autumn) application on two type winter rape varieties development in autumn. Winter rape biometrical parameters, dry matter content and dry mass per square m of leaves were estimated. Sowing date affected height of growth point, root neck diameter, plant and root mass, main root length significantly (p is less than 0.05). Sowing rate affected only some indices significantly in autumn 2007. Fungicide (juventus 90 s.c. - metconasol 90 g LE-1) application also affected rape plant biometric parameters during autumn depending on conditions of research year - height of growth point decreased only in year 2007, effect on number of leaves per plant was observed in both trial years, plant weight (2007) and root length (2008) were affected for hybrid variety. Sowing date showed effect on dry matter content in leaves as well as on dry matter mass of leaves per 1 square m. Fungicide application increased dry mass of leaves per 1 square m in two earlier sowing dates. Results are important also for outline of further research directions evaluating significance of above mentioned factors for winter rape wintering in Latvia.
Mostrar más [+] Menos [-]The evaluation of Rhizobium leguminosarum strains effectiveness in field beans (Vicia faba L.) at different soil microbiological activity
2009
Ansevica, A., Latvia Univ. of Agriculture, Jelgava (Latvia) | Alsina, I., Latvia Univ. of Agriculture, Jelgava (Latvia) | Steinberga, V., Latvia Univ. of Agriculture, Jelgava (Latvia)
The inoculation of the legume seed material with active nitrogen fixing bacteria strains before sowing has a significant role for the increase of the legume yield. Inoculation can improve crop yields in cases where appropriate rhizobia are not present in the soil or the soil contains a significant proportion of non-nodulating or ineffective nitrogen-fixing strains. The aim of the investigation was to detect the effectiveness of Rhizobium leguminosarum strains in field beans at different soil microbiological activity. The experiment was conducted at the Institute of Soil and Plant Sciences of the Faculty of Agriculture of the Latvian University of Agriculture from the 5th of June till the 17th of October 2008. The field bean (Vicia faba. L) cultivars - 'Ada', 'Lielplatones', Rhizobium leguminosarum bv. vicia strains No. 110; 408; 501 and 2 types of soils (with different microbiological activity) were used in vegetation pot experiment. The highest shoot dry matter was observed in cultivars cultivated in soil with higher microbiological activity. The highest pod dry matter was observed in cultivars cultivated in soil with higher microbiological activity. The highest total nitrogen amount was in field beans cultivated in soil with lower microbiological activity. Rh. leguminosarum strain resistance to streptomycin decreases with the plants age, from anthesis forward in both soil types and both cultivars. The fingerprinting showed significant difference between Rh. leguminosarum strains.
Mostrar más [+] Menos [-]Influence of biological products - Trihodermin and BioMikss on the yield of lettuce and strawberries
2009
Balode, A., Latvia Univ. of Agriculture, Jelgava (Latvia)
Under open environmental conditions, Trihodermin and BioMikss were used for trial purposes to study lettuce (Lactuca sativa L.) and strawberry (Fragaria x ananassa Duch) yields in 2008. Experiments were carried out in the Region of Riga at the farm 'Pukulejas'. The lettuce cultivar 'May King' and the strawberry cultivar 'Senga Sengana' were both used in the trial. The purpose of the trial was to evaluate the use of biological products when applied on the above mentioned trial plants. In the field trial, both Trihodermin and BioMikss in dry powder form in peat mixture were applied for soil treatment 10 kg haE-1. Trihodermin contains cells of microscopic fungus Trichoderma harzianum 8-21 and Trichoderma viride 1-5. BioMikss is a mixture of microorganisms, containing cells of seven various bacteria (Azotobacter chroococcum 23, Polyangium cellulosum 5-t, Polyangium 56, Pseudomonas putida 48-t, Rhizobium meliloti 15, Streptomyces griseoviridis P-t and Streptomyces cellulosae D) and cells of two various fungus (Trichoderma harzianum 7-t and Trichoderma viride A-L). Three times during the growing period Trichodermin and BioMikss water solution 100 g kgE-1 was applied on the trial plants. When compared to non-treated plants, significantly increased yield was observed on BioMikss-treated lettuce. A significantly increased yield was also observed on BioMikss-treated strawberries. The results of the experiments showed that in open environment, both strawberry and lettuce plants treated with BioMikss showed resistance to the grey mould, caused by a parasitic fungus Botrytis cinerea. The results prove that biological products, by environmentally friendly means, revitalize soils, protect plants, and enhance growth, immunity and productive potential.
Mostrar más [+] Menos [-]Diversity of non-starter lactic acid bacteria in Latvian semi-hard cheeses
2009
Mikelsone, A., Latvia Univ. of Agriculture, Jelgava (Latvia) | Ciprovica, I., Latvia Univ. of Agriculture, Jelgava (Latvia)
The most non-starter lactic acid bacteria (NSLAB) isolated from semi-hard cheeses are heterofermentative and handled as one of the reasons of cheese off-flavours and yield defect but at the same time majority of researches argued positive effect of NSLAB on cheese flavour formation and diversification due to rendered compounds of chemical reactions. The amount of NSLAB in cheese varies from 10 at the beginning of ripening to 105 cfu mlE-1 within 6-8 weeks. The aims of this paper were to establish diversity of NSLAB in commercial samples of Krievijas and Holandes cheeses, and to evaluate the effect of ripening temperatures on NSLAB in the trials of Krievijas cheese. A total of 12 commercial cheese samples from seven different Latvian manufacturers and trials from one cheese manufacturer were examined. The trials were ripened for 60 days at different temperatures - 6 deg C and 12 deg C. Serial dilutions of each cheese sample (1:1000 and 1:10 000) in saline were made. NSLAB were cultivated using MRS media. Strain identification was performed by the API 50 CHL system (BioMerieux, Marey l'Etoile, France). In commercial samples of Krievijas cheese dominance of L. curvatus was observed, simultaneously L.plantarum and L.paracasei subsp. paracasei were isolated. Whereas in Holandes cheese samples dominance of L.paracasei subsp. paracasei was noted and L.plantarum, L.curvatus, L.rhamnosus and L.acidophilus were isolated. In the trials ripened at different temperatures prevalence of L.curvatus was noted. Concentration of Lactobacillus spp. varied from 104 cfu mlE-1 on the first day of ripening and reached the highest concentration (106 cfu mlE-1) after 6 weeks of ripening.
Mostrar más [+] Menos [-]Changes in quality of parents stock hens meat during chilled storage
2009
Ramane, K., Latvia Univ. of Agriculture, Jelgava (Latvia) | Galoburda, R., Latvia Univ. of Agriculture, Jelgava (Latvia)
The aim was to study changes of chemical composition (fat content, protein content), pH and colour of poultry meat during chilled storage. Various criteria are used for evaluation of bird and carcass quality, while the combination of several indices determines the quality of poultry meat, which has an important role in the following meat processing and quality of end product. Chilled poultry meat is offered in retail and it is used in processing plants for various meat products production. Chemical composition (fat content, protein content), pH and colour are important quality determinants. Hens' meat is cheaper compared to broiler meat; therefore its use in processing is profitable. Parents stock hens of the cross Ross 308 were used for the study. Parent stock hens were fed compound feed. After chilling a hen fillet [musculus pectoralis], hen thighs [musculus biceps] and hen drumsticks [musculus gastrocnemius; musculus fibularis longus] were separated from carcasses. The obtained products were refrigerated at temperature +1+-0.5 deg C. The analyses were performed 1 day after slaughter and on the 5th day of storage. The following parameters were analysed: pH value (3510pH Meter - JENWAY); total protein content (LVS ISO 937:1978); fat content (LVS ISO 1443:1973); colour changes (Color Tec-PCM; software ColorSoft QCW for colour data analysis). The analysed parameters significantly differ in 'white' and 'red' poultry meat, and in various cuts of 'red' meat.
Mostrar más [+] Menos [-]Chromatographic profiling of hydrophilic metabolites from tubers of different potato cultivars
2009
Zhokhov, S., Swedish Univ. of Agricultural Sciences, Upsala (Sweden). Dept. of Food Science | Alstroem, S., Swedish Univ. of Agricultural Sciences, Uppsala (Sweden). Dept. of Forest Mycology and Pathology | Andersson, B., Swedish Univ. of Agricultural Sciences, Uppsala (Sweden). Dept. of Forest Mycology and Pathology | Jastrebova, J., Swedish Univ. of Agricultural Sciences, Upsala (Sweden). Dept. of Food Science
Potato is an important source of nutrients and bioactive compounds with profitable effect for health, such as antioxidants, vitamins and essential amino acids. The knowledge about metabolite composition of various potato cultivars is necessary to facilitate development of new cultivars with desirable properties. In the present study, the hydrophilic metabolite composition of six potato cultivars with different resistance against potato late blight disease was analyzed. For this, an HPLC-based method was developed and used for the analysis of water-ethanol extracts of freeze-dried potato tubers. Significant differences in concentrations of adenosine, chlorogenic acid, and rutin were revealed. Some other metabolites were found to be cultivar-specific.
Mostrar más [+] Menos [-]Technical and environmental issues of stump harvesting for biofuel production in Latvia
2009
Lazdins, A., Latvian State Forestry Research Inst. Silava, Salaspils (Latvia) | Hofsten, H. von, Skogforsk - The Forest Research Institute of Sweden, Uppsala (Sweden)
This article represents the results of the research project 'Forest energy from small-dimension stands, infra-structure objects and stumps' realized in cooperation between Joint stock company Latvijas valsts meži (Latvia's state forests), SKOGFORSK (The Forestry Research Institute of Sweden) and Latvian State Forestry Research Institute Silava. The article is covering issues related to the results of stump harvesting field study realized in November, 2008. A scope of the study was to estimate costs of stump harvesting and to evaluate working methods and influencing factors related to extraction of stumps. Better harvesting conditions (flat landscape and lack of stones in soil) led to increased productivity of stump extraction in Latvian trials (5.2 tdry (tdry - tons of dry mass) of stumps per effective hour (E0-h)) in comparison to average figures in Scandinavian studies. Load sizes of the forwarder ranged from 5.5 to 9.3 t which is about half of the maximum load of forwarder. Average productivity of forwarding was 6.3 tdry E0-hE-1. Productivity of stump transport (distance - 7 km) was 3.5 tdry E0-hE-1. Productivity of comminution was 10 tdry E0-hE-1. Prime cost of the stump harvesting, including extraction, forwarding, stump transport (7 km one direction), comminution and chip transport (50 km one direction) was 6.3 LVL LVmE-3 (LV - loose volume). 'Environmental footprint' of the stump harvesting in terms of carbon (C) emissions was 2.5 kg C LVmE-3 of wood chips at terminal. Stumps demonstrated considerably higher heat value (5.7 MWh tdryE-1 against 4.7 MWh tdryE-1 for the hog fuel from a slash).
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