Maize yield and quality are affected by many factors, including production practices, diseases, pests, and differences in the climate. Usually it is not possible to do much to change the effect of temperature, but it is important to grow better adapted or characterized with right maturity rating hybrids. The paper is aimed to determine the impact of accumulated growing degree days (GDD) on maize development, organic dry matter yield, ODM and chemical composition of maize hybrids. A field trial was carried out in the Research and Study farm ’’Vecauce’’ of the Latvia University of Agriculture (LLU) from 2008 till 2010. Ten (in 2008), eleven (in 2009) and fifteen (2010) maize hybrids with different maturity ratings according to FAO numbers (FAO 180-340) were harvested at three different times beginning on 5 September at fourteen-day intervals. GDD were calculated when maize reached a certain growth stage (full emergence, first tassels, full tassels, first ears, full ears, specific harvest date) to characterize conditions for maize growing in a specific year. Composition of fresh maize was analyzed for all hybrids using standard methods. Results were statistically processed using methods of correlation and regression analysis. Our results presented evidence that ODM yield in 2008 and 2009 on last harvest dates was lower than that on the first harvest date in 2010. Organic dry matter yield was higher in years when more GDD were accumulated. Results also showed that GDD negatively correlated with the total N, protein, fibre cellulose, hemi-cellulose, NDF, and ADF concentration.

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.

The contents of soluble solids, acids and their ratio as well as phenol content are important indices for quality evaluating of sour cherry fruits. These parameters are influenced by the cultivar and growing conditions. The trial was carried out at the Latvian State Institute of Fruit-Growing to evaluate the effect of woodchip mulch and drip irrigation on fruit quality of sour cherry cultivars 'Bulatnikovskaya', 'Desertnaya Morozovoi', 'Latvijas Zemais', 'Orlica', 'Shokoladnica', 'Tamaris', and 'Zentenes'. The biochemical composition of the fruits was analyzed in 2009 and 2010. The content of soluble solids was determined with the method of refractometry; the content of total acids by titrating with 0.1N NaOH; the total content of phenols with the method of spectrometry. The content of total soluble solids in sour cherry fruits was decreased by use of woodchip mulch. The content of acids, the ratio of soluble solid content to the acid content and the content of the phenols was not significantly influenced by woodchip mulch and drip irrigation. The cultivar 'Desertnaya Morozovoi' showed the highest soluble solid content in the fruits, the cultivar 'Latvijas Zemais' - the highest acid content, and cultivar 'Tamaris' - the highest phenol content in the fruits.

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.

This study investigates different environmental effects on birth weight, weaning weight, and pre-weaning daily gain using different statistical models in the Latvian sheep population. The coefficients of determination (R2) were used to estimate the extent of different non-genetic factors influencing birth weight, weaning weight, and pre-weaning daily gain. Data were collected of 4460 lambs born in 36 herds during 2008 to 2010. The birth weight (on average 4.1 ± 0.01 kg), weaning weight (on average 21.0 ± 0.07 kg) and pre-weaning daily gain (on average 242.1 ± 0.93 g) was significantly affected by type of birth and sex, lambing age of dam (covariate) and herd, year, season of birth (p is less than 0.01). Coefficients of determination were estimated from 0.14 to 0.42 for birth weight, from 0.13 to 0.49 for weaning weight, and from 0.10 to 0.46 for pre-weaning daily gain. The results show that when the fixed effects of HYS (interaction between the herd, year, and season of birth) were included it improved the quality of the statistical model most of all, because higher determination coefficients were obtained for all traits: 0.42 for birth weight, 0.49 for weaning weight, and 0.46 for pre-weaning daily gain.

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.

The current research focuses on the study of anthocyanin content changes in Latvia wild growing as well as cultivated cranberries during convective and microwave vacuum drying. The research was accomplished on fresh Latvian wild and cultivated cranberries. The berries before drying in a convective drier were pre-treated using perforating, steam-blanching and halving; berries dried in microwave vacuum drier – using steam-blanching and halving; part of berries was dried in microwave vacuum drier without pre-treatment (whole berries). For air drying experiments, a convective dryer “Memmert” (Model 100-800) was used. For drying experiments in microwave vacuum a dryer „Musson-1” was used. Anthocyanin was determined by means of spectrophotometric method. Data are expressed as mean ± standard deviation; variance analysis, homogeneity were used for the evaluation of changes of anthocyanin in cranberries during drying depending on pre-treatment methods. The initial content of anthocyanin among wild and cultivated fresh cranberries was differing: very similar anthocyanin content was detected in cranberry cultivars ‘Pilgrim’ and ‘Early Black’, it was on average three times higher comparing to wild fresh cranberries. However, the lowest anthocyanin content was detected in wild fresh cranberries – 306.81 ± 4.19 mg 100gE-1 (in dry matter). With the probability of 95%, detected by means of the analysis of variance, it may be presumed, that pre-treatment method of cranberries influenced anthocyanin changes during convective and microwave vacuum drying (p=0.001, is less than =0.05). Halving is advisable as a pre-treatment method for berries processing in a convective or microwave drier, because decrease in anthocyanin content is smaller.

Marinating is a simple technological treatment used to improve the tenderness and flavour of meat by soaking it in an aqueous solution which is composed of different ingredients. That also increases water brinding capacity of meat, thus reducing cooking losses and improving meat juiciness. The aim of current research was to investigate a degree of preference of marinated roasted venison meat. The red deer (Cervus elaphus) meat samples were obtained from a local farm “Saulstari 1”. The experiments were carried out in the Latvia University of Agriculture, Faculty of Food Technology. Prepared samples were marinated at 4 ± 2 deg C temperature in the refrigerator for 48 ± 1 h. After marinating, venison meat samples were wrapped in aluminium foil, and cooked on a pre-heated double hotplate grill at 200 ± 2 deg C temperature until ready to eat (45 ± 2 min). The cooked hot meat samples were sensory evaluated. The sensory evaluation was carried out by using the nine point hedonic scale – ISO 4121:2003. The sensory evaluation of meat sample with thyme and juniper berries showed that the degree of preference was not so high (approximately – 6.0 points). For the venison meat preliminary treatment mayonnaise and tomato sauce marinades possibly could be recommended for acquiring better sensory properties of ready to eat product.

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.

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.