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The influence of cow feed enriched with carrots on milk quality and nutritional value Полный текст
2011
Antone, U., Latvia Univ. of Agriculture, Jelgava (Latvia);Latvia Univ. of Agriculture, Sigulda (Latvia). Research Inst. of Biotechnology and Veterinary Medicine Sigra | Sterna, V., Latvia Univ. of Agriculture, Sigulda (Latvia). Research Inst. of Biotechnology and Veterinary Medicine Sigra | Zagorska, J., Latvia Univ. of Agriculture, Jelgava (Latvia)
β-Carotene (BC) and a-tocopherol in milk fat have positive implications in human nutrition, besides the specifically protecting polyunsaturated fatty acids from oxidation. To determine the possible effect on some milk components, nutritional value and lipid stability of including carrots in the diet of lactating cows, ten cows were selected in a dairy farm and divided into 2 groups (control and experimental) by 5 cows in each. In experimental group's diet additionally 7 kg carrots per cow per day were included. Individual cow milk samples were obtained 1 day before feed enrichment, in days 7, 24, 35, 42 (during the feed enrichment), and 1 week after feed enrichment. Analyses of milk fat, protein content, somatic cell count (SCC), retinol, BC, vitamin C, tocopherols, immunoglobulins (Ig), lysozyme, fatty acids (FA) were made, and milk yield was measured. Supplying cow diet with carrots showed a tendency to improve milk quality by promoting the faster decrease of SCC, and significantly (p is less than 0.05) increasing Ig and lysozyme content, thus potentially improving milk nutritional value. The vitamin content rose significantly (p is less than 0.05) by retinol and tocopherol contents, but b-carotene content increase in milk was not observed. Also milk fatty acid (FA) stability changes during 5 day storage in temperature of 4 - 6 deg C were not observed.
Показать больше [+] Меньше [-]Antiradical activity of different barley varieties and malt types Полный текст
2011
Dabina-Bicka, I., Latvia Univ. of Agriculture, Jelgava (Latvia) | Karklina, D., Latvia Univ. of Agriculture, Jelgava (Latvia) | Kruma, Z., Latvia Univ. of Agriculture, Jelgava (Latvia)
Cereal grains have long been thought to be less important sources of antioxidants than fruits and vegetables although they contain many antioxidants and are major dietary components worldwide. The aim of the current research was to study and compare an antioxidant activity (AOA) and total phenolic content (TPC) of different barley varieties and malt types as well as to evaluate possible interconnection between TPC and AOA of barley and malt samples. The research was carried out on four lines of hull-less barley ‘3528’; ’L-400’; ’3475’; ‘3537’ and one variety of flaky barley ‘Klass’ grains, which were cultivated in Latvia in 2010, and their corresponding malt. Commercial sorts of malt - Pilsener, Munich, Caramel and Dark were used in the research to compare with the malt produced in the laboratory scale. The antioxidant potential of barley and their products is analyzed by the 2,2-diphenyl-1-picrylhydrazyl (DPPH) assays. Total phenolic content of barley and malt samples was determined according to the Folin-Ciocalteu spectrophotometric methods. The values of DPPH radical scavenging activity for 5 barley samples ranged from 4.57 to 5.89 μmol TE gE-1 DW. The total amount of phenols ranged from 1.96 to 2.43 mg GAE gE-1 DW for unprocessed barley samples and from 2.5 to 3.4 mg GAE gE-1 DW for their corresponding malt. TPC of malt commercial sort ranged from 3.5 to 6.7 GAE gE-1 DW. The increase of TPC for commercial malts is strongly related with Maillard reaction products.
Показать больше [+] Меньше [-]Assessment of apple cultivar quality and selection of the most suitable apple cultivars for fresh cut salad production Полный текст
2011
Krasnova, I., Latvia Univ. of Agriculture, Jelgava (Latvia);Latvian State Inst. of Fruit-Growing, Dobele (Latvia) | Karklina, D., Latvia Univ. of Agriculture, Jelgava (Latvia) | Seglina, D., Latvian State Inst. of Fruit-Growing, Dobele (Latvia) | Juhnevica, K., Latvian State Inst. of Fruit-Growing, Dobele (Latvia) | Kviesis, J., Latvian State Inst. of Fruit-Growing, Dobele (Latvia)
Apples (Malus domestica L.) are the most consumed fruits in Latvia. Apples are used as one of ingredients for the fresh cut fruit salad preparation. The evaluation of physical, chemical and sensory properties is important; they could influence the nutritional value of fruit salads. The objective of this research is to select for fresh cut salad production the most appropriate apple cultivars grown in Latvia and evaluate their physical, chemical and sensory properties. Ten commercial apple cultivars grown in Latvia were selected for experiments: ‘Zarya Alatau’, ‘Saltanat’, ‘Belorusskoe Malinovoe’, ‘Auksis’, ‘Antei’, ‘Sinap Orlovskii’, ‘Orlik’, ‘Korichnoe Novoe’, ‘Alesya’, ‘Kovalenkovskoe’. The research was carried out in the Latvia State Institute of Fruit Growing (LSIFG), the years 2010 – 2011. The apple physical indices (average mass, diameter of fruit, flesh consistency and colour) and chemical parameters (total sugar, soluble solids content, titratable acidity ratio between soluble solids and titratable acidity) were analyzed as well. The sensory properties were determined using quantitative descriptive analysis and affective method by hedonic scale. The physical and chemical properties of fruits were analyzed and for fresh cut fruit salad production as the best the following apple cultivars: ‘Zarya Alatau’ and ‘Sinap Orlovskii’ were selected; however, the cultivars ‘Antei’, ‘Auksis’ and ‘Alesya’ could be successfully used for mentioned aim as well.
Показать больше [+] Меньше [-]Occurrence of Campylobacter spp. on fresh broiler chicken carcasses at retail level in Latvia Полный текст
2011
Kovalenko, K., Latvia Univ. of Agriculture, Jelgava (Latvia) | Roasto, M., Estonian Univ. of Life Sciences, Tartu (Estonia) | Ruzaike, A., Latvia Univ. of Agriculture, Jelgava (Latvia) | Liepins, E., Latvia Univ. of Agriculture, Jelgava (Latvia)
Campylobacter jejuni and Campylobacter coli are the most commonly registered cause of human campylobacteriosis. Mainly the source of these bacteria is from the contaminated foods of animal origin and especially broiler chicken (Gallus gallus domesticus) meat. The aim of the present study was to determine the occurrence of Campylobacter spp. in fresh broiler chicken carcasses at the retail level in Latvia. Sampled broiler chicken carcasses originated from two biggest Latvian chicken companies/slaughterhouses and samples were taken during the year 2010. A total of 56.7% of the fresh broiler chicken carcass samples were positive for Campylobacter. There was no distinct seasonal variation in Campylobacter contamination in Latvia. Additionally, only slight differences between the proportions of Campylobacter-positive broiler chicken meat samples of the studied companies were determined.
Показать больше [+] Меньше [-]Efficacy of the first large-scale rabies oral vaccination campaigns in Latvia Полный текст
2011
Olsevskis, E., Latvia Univ. of Agriculture, Jelgava (Latvia);Food and Veterinary Service, Riga (Latvia);Institute of Food Safety, Animal Health and Environment BIOR, Riga (Latvia) | Liepins, E., Latvia Univ. of Agriculture, Jelgava (Latvia) | Lamberga, K., Food and Veterinary Service, Riga (Latvia) | Rodze, I., Institute of Food Safety, Animal Health and Environment BIOR, Riga (Latvia)
Rabies is present in the entire territory of Latvia and as a zoonosis poses risk to both human and animal health. The disease is also endemic in countries bordering with Latvia, namely Lithuania, Estonia, Russia and Belarus. Reservoirs for the rabies virus (RABV), the causative agent of the disease in Latvia, are the red fox (Vulpes vulpes) and the raccoon dog (Nyctereutes procyonoides). The first large-scale oral rabies vaccination campaigns using aircrafts were carried out in spring and autumn 2005 using Fuchsoral® SAD B19 oral vaccine baits. In total, 1,894 wild animals (1,366 foxes and 528 raccoon dogs) were hunted in vaccinated areas to evaluate the efficacy of the campaign. After spring and autumn vaccination campaigns, 51.6% of the fox and raccoon dogs were positive for tetracycline. Herd immunity was found in 50.5% of foxes and raccoon dogs using FAVN test and only in 14.8% using ELISA test. After oral vaccination campaigns, rabies incidence decreased in vaccinated area, however, an increase of the incidence was observed in unvaccinated area. Despite the slight increase in rabies incidence in Latvia in 2006 compared to 2005, in 2005 only 141 rabies cases (30%) were found in the vaccinated area whereas 330 cases were detected in the unvaccinated area.
Показать больше [+] Меньше [-]Development of experimental equipment for vegetable oil fuel research Полный текст
2011
Birkavs, A., Latvia Univ. of Agriculture, Jelgava (Latvia) | Dukulis, I., Latvia Univ. of Agriculture, Jelgava (Latvia)
The European Parliament and Council Directive 2003/30/EK ‘On the promotion of the use of biofuels and other renewable fuels for transport’ determines that pure or straight vegetable oil, produced from oil plants by pressing, extracting or comparable procedures, crude or refined but chemically unmodified, compatible with common engines, and corresponding to emission requirements, is also considered as biofuel. The biggest problems imposed by these conditions are directly associated with the carrying-out of the emission requirements, because when using vegetable oil as a fuel, usually increases the composition of the solid particles and nitrogen oxides in exhaust gases, that not only adversely affect the environment, but also is a serious threat to human health, and as a result trying to save the world from the global warming, human health continues to deteriorate. It is therefore necessary to carry out studies and find solutions to reduce harmful emissions from diesel engines when using vegetable oil fuel. For more qualitative and effective research on vegetable oil fuel emissions, the equipment for vegetable oil fuel testing has been developed. This equipment allows fast checking of theoretically proposed hypotheses and detailed calculations for vegetable oil fuel combustion processes and objective data acquisition. The equipment consists of the classic diesel engine adapted for work with vegetable oil and is equipped with several high-precision devices to get and store the measuring data. During pilot tests the optimal measuring modes (engine rotation frequencies, number and duration of repetitions) for further research are estimated.
Показать больше [+] Меньше [-]Evaluation of study programme external quality Полный текст
2011
Sproge, S., Latvia Univ. of Agriculture, Jelgava (Latvia)
Quality assessment of a study programme is a topical issue in the single education area. Quality is not a unequivocal term in higher education area, which lends itself to many understandings and interpretations according to different criteria. The best practice of software engineering may be applied for the study programme evaluation if by analogy it is viewed as software product. Study programme similar to software product has internal and external quality. Students as direct users of the study programme may be engaged in the evaluation of its external quality, in case the evaluation of internal quality of the study programme is mainly based on internal resources of a higher education institution. The paper provides the methodology for evaluation of external quality of a study programme based on software product quality model and quality assurance standards. Approbation of the methodology was started in 2009 at the Faculty of Information Technologies, where students evaluated external quality of undergraduate study programmes. Results obtained during the approbation lead to the conclusion that the chosen methodology ensures significant information for the enhancement of quality of a study course and simultaneously the entire study programme.
Показать больше [+] Меньше [-]The use of black-box modelling in bioprocess scale-up Полный текст
2011
Mednis, M., Latvia Univ. of Agriculture, Jelgava (Latvia)
Computer models of bioprocesses have become an essential tool in biotechnology. This paper describes various bioprocess scaleup releated problems. The problems at different scales are explained. In this paper the use of computer model in E.coli fermentation scale-up from shake flask to laboratory scale bioreactor is discussed. A black box modelling approach was used. Fermentation results have been visualized and discussed. The computer model created in Matlab environment was used for bioprocess behaviour prediction. Possible bioprocess scale-up software improvements and bioprocess optimization are discussed.
Показать больше [+] Меньше [-]Low-cost electrical energy monitoring method with wireless ICT Полный текст
2011
Apse-Apsitis, P., Riga Technical Univ. (Latvia) | Avotins, A., Riga Technical Univ. (Latvia | Ribickis, L., Riga Technical Univ. (Latvia
The electricity consuming end-user profile has changed in latest years, due to development of new electrical devices with increased functionality and complexity. Also increasing number of electricity consuming equipment that is available to end-user, makes very hard to identify real electricity consumption of each device. The existing wall plug digital power meters are too expensive for long-term power metering of each consuming device. The article describes a different approach of power metering system that lowers the costs and price of needed metering equipment. A new concept of low-cost energy monitoring system with wireless communication is developed.
Показать больше [+] Меньше [-]Socio-economic characteristics and perceptions of cattle keepers and constraints to cattle production in western Kenya Полный текст
2011
Amimo, Joshua O. | Thumbi, Samuel M. | Inyangala, B.A.O. | Jung'a, J.O. | Mosi, R.O.
A cross-sectional survey was done in two Districts in Western Kenya to determine the socio-economic characteristics and perceptions of the cattle types kept. This involved socio-economic profiles of households, herd structure, reasons for keeping specific types of cattle and production and marketing constraints together with desired policy interventions to address the constraints. A total of 210 farmers randomly selected were interviewed. The data was analysed using Statistical Analysis System program. The majority of farmers (84%) were males. The households surveyed had an average family size of 8 (± 4.7) members. The mean land holding was 7.8 acres, with 98% of them owning the land. Most of the farmers (64%) in the two districts were literate and were involved in farming (95%) as the primary livelihood. The majority (80%) of the households preferred keeping indigenous zebu cattle over the exotic cattle. The first three reasons for keeping zebu cattle were, in that order, work, especially ploughing (91%), milk (74%) and as a repository for wealth (32%), which accounted for about 62% of the respondents. Diseases (86%), inadequate and low quality feed (12%) and high cost of drugs (2%) were the major constraints to livestock productivity. The farmers also identified lack of market (48%), poor infrastructure (39%) and misuse by the middlemen traders (12%) as main marketing constraints. The survey showed that there is need for the effective implementation of policies on adequate financial aid and regulation of farm input prices to the farmers as well as improved livestock extension services to enhance the production of ruminant livestock.
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