Refine search
Results 291-300 of 2,185
The evaluation of oil-flax (Linum usitatissimum L.) quality parameters for biofuel production Full text
2011
Poisa, L., Latvia Univ. of Agriculture, Jelgava (Latvia) | Adamovics, A., Latvia Univ. of Agriculture, Jelgava (Latvia)
Oil-flax has a wide range of utilization possibilities, inclusive of bioenergy production. In our research evaluated out two oil-flax varieties 'Scorpion' and 'Flanders' after the calorific value, oil, lignin, and ash content; and also the chemical composition in 2008 -2010. The results show that oil-flax shoves have a high calorific value and high lignin content but a low temperature for ash fusion. It was established that the growth year and some unexplored factors have influence on the ash content. The oil content in the seeds was 336-458 g kgE-1, depending on the chosen variety. The flax shoves can be used as a supplement for biofuel combustion, as they have a low fusion temperature, a high calorific value, but a comparatively low yield makes oil-flax unprofitable to grow for biofuel production.
Show more [+] Less [-]Evaluation of some qualitative characteristics of new plum cultivars Full text
2011
Gravite, I., Latvia Univ. of Agriculture, Jelgava (Latvia);Latvian State Inst. of Fruit-Growing, Dobele (Latvia) | Kaufmane, E., Latvian State Inst. of Fruit-Growing, Dobele (Latvia) | Abolins, M., Latvia Univ. of Agriculture, Jelgava (Latvia)
A study was done at the Latvia State Institute of Fruit-Growing, evaluating new domestic plum (Primus domestica L.) selections, for which in 2008 -2010 some fruit quality characteristics were studied. In result of evaluation four new cultivars were selected from the breeding material and in 2010 handed in for cultivar registration in Latvia. Cultivar 'Ance' is early ripening one month before 'Victoria'. Cultivar 'Adele' is medium ripening one week before 'Victoria'. Fruits keep well in cool storage. Cultivar 'Sonora' is medium ripening one week after 'Victoria' and self-fertile. Fruits of this cultivar keep well in cool storage, too. Cultivar 'Lotte' is medium-late ripening two weeks later than 'Victoria', and is partially self-fertile. Average of three years, the highest soluble solids content was found for cultivar 'Adele' (13.28 Brix%), but cultivar 'Sonora' had the total content of acids (1.28 g 100 gE-1). Significant changes in flesh firmness were observed at different storage times for cultivars 'Ance' and 'Lotte'. Significant variations in the total content of acids were determined for 'Ance'. Whereas cultivar 'Sonora' demonstrated substantial fluctuations in soluble solids content. Correlations between firmness and soluble solids content were observed for cultivars 'Ance' (r=-0.731), 'Adele' (i=-0.436) and 'Sonora' (r=0.526). Cultivar 'Lotte' produced correlations between firmness and total content of acids (i=-0.536). Significance of interaction was determined within cultivars, years, and years x cultivars.
Show more [+] Less [-]Potassium removal with grass in an apple orchard under influence of mulch and irrigation Full text
2011
Surikova, V., Latvia Univ. of Agriculture, Jelgava (Latvia) | Karklins, A., Latvia Univ. of Agriculture, Jelgava (Latvia)
Potassium (K) is one of the most important nutrients necessary for many life functions of plants, like shoot growth, fruit and flower bud set, and fruit size. The aim of this study was to determine the content of potassium in orchard lawn for reduction of potassium fertilizer application and to include the potassium from mown grass into K balance and turnover calculation. The investigation was done at the Latvia State Institute of Fruit-Growing in Dobele in 2009, on the basis of an established field experiment planted in 1997 with apple (Mains domestica Borh.) cultivar 'Melba' (rootstock B9), trees spaced at 1.5 x 4 m distances. Three different treatments of soil moisture management were compared: control, sawdust mulch, and fertigation. Soil of the experimental plot was Pisocalcic Cutanic Luvisol (Hypereutric, Hyposkeletic); loam. Organic matter - 25 g kgE-1, soil reaction pH - 6.5. Plant-available P was 130.9, K - 157.7, and Mg - 102.2 mg kgE-1. Inter-row strips were covered with grass vegetation (Lolium perenne L. and Poa pratensis L.). Grass samples were collected during cutting, 3 times per season of 2009: May 19, June 20, and August 11. The uptake and removal of potassium was calculated as kilograms per hectare area. The concentration of potassium in the lawn and the height of grass growth were significantly influenced by the mowing time and the soil moisture treatment. These results can be a base for further studies of potassium turnover in an orchard, as well as for fertilizer planning and management.
Show more [+] Less [-]Changes in serum immunoglobulins concentration of newborn calves Full text
2011
Eihvalde, I., Latvia Univ. of Agriculture, Jelgava (Latvia) | Kairisa, D., Latvia Univ. of Agriculture, Jelgava (Latvia)
The changes in the serum immunoglobulins concentration were investigated in newborn heifers from birth to 7 days of age. The mothers of calves were determined serum and colostrum immunoglobulins (Ig) concentration. The research was carried out at the Latvia University of Agriculture (LLU), in dairy farm ''Ligotnes'' of the Research and Study Farm ''Vecauce'', in a loose housing system with 530 cows, of which 430 were milking cows. The cows during the dry period were kept tethered in the farm. Eighteen heifers and their dams (Latvian Brown and Holstein breeds) which calved from 30 November 2010 to 23 January 2011 were used in this study. The calves' serum total immunoglobulin concentration at birth was 9.0 ±1.31 mg dLE-1 (or 0.09 mg mLE-1), and after 24 hours (h) it increased significantly to 4.3 mg dLE-1 (or 0.043 mg mLE-1), p is less than 0.05. The immunoglobulin G (IgG) concentration in calf serum after birth was 6.8 ±1.50 mg dLE-1 (or 0.068 mg mLE-1), and after 1 day and after 7 days it did not change significantly. The average Ig serum concentration in cows was 12.6 ± 1.36 mg dLE-1(or 0.126 mg mLE-1), and Ig concentration in colostrum was 18.5 ± 1.68 mg mLE-1. On average, close correlation (r=0.56) was found between cow blood serum IgM and colostrum IgM. Correlation between cow and calf IgG serum concentration proved to be weak (r=0.49).
Show more [+] Less [-]Relation between milk protein and urea content in different farms Full text
2011
Ruska, D., Latvia Univ. of Agriculture, Jelgava (Latvia) | Jonkus, D., Latvia Univ. of Agriculture, Jelgava (Latvia)
Milk production and milk composition are of prime economic importance for farmers. It is well known in dairy management that the balanced feeding and holding technology is an important lever by which milk production and milk composition can be modified. The objectives of this work are to establish relation among milk protein and urea content in different farms. Four farms represent three cow breeds (Holstein Black and White, Latvian Brown, and cross breed XP). Individual cow milk samples (n=8400) were collected monthly from September 2009 to November 2010. Milk samples were analyzed for total protein, casein, fat, lactose, and urea content with instrumental infrared spectroscopy method. The average milk yield in farms was significantly different (from 26.8 to 16.0 kg per control day), and average protein content varied from 3.32 g kgE-1 to 3.62 g kgE-1. The urea content in cow milk was between 21.3 to 42.6 mg 100 mLE-1. The average protein content was higher and significantly (p is less than 0.05) different in first yield level (up to 15 kg) for all farms. Overall, in different farm and milk yield levels correlation between protein and urea was low or very low. In the farm C, average urea content ranged between 30.0 and 60.0 mg 100 mLE-1, which indicated problems in feeding or management in the farm. It was established that milk productivity traits significantly (p is less than 0.05) varied in farms with different dairy cow holding and feeding technologies and milk protein and urea content significantly (p is less than 0.05) varied for cows with different milk yield per day.
Show more [+] Less [-]The influence of cow feed enriched with carrots on milk quality and nutritional value Full text
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.
Show more [+] Less [-]Antiradical activity of different barley varieties and malt types Full text
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.
Show more [+] Less [-]Assessment of apple cultivar quality and selection of the most suitable apple cultivars for fresh cut salad production Full text
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.
Show more [+] Less [-]Occurrence of Campylobacter spp. on fresh broiler chicken carcasses at retail level in Latvia Full text
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.
Show more [+] Less [-]Efficacy of the first large-scale rabies oral vaccination campaigns in Latvia Full text
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.
Show more [+] Less [-]