By using analytical correlations derived as a result of theoretical research, a computer algorithm has been worked out for simulating the functions of the plough body and the forces exerted by soil upon the operating parts, as well as its draft resistance. These correlations allow to determine the draft resistance of the plough depending on the parameters of its body, as well as to evaluate the impact of the physical and mechanical properties of soil, such as friction upon it. The greatest influence upon the draft resistance is exerted by soil hardness, density and slip resistance along the surfaces of the operating parts. The latter is also affected by soil adhesion, which particularly manifests itself in wet clay soils at lower temperatures. It has been clarified that the friction resistance constitutes 46–62% of the total draft resistance of the plough body. The main ways of lowering the friction resistance and the total draft resistance of the plough are the introduction of a more rational design of its body having optimum parameters, decreasing the resistance of the share-mouldboard surface and the values of reactions of the supporting surfaces, as well as the application of antifriction materials and better modes of joining with tractors.

Researchers have found that morphology of muscle structure (original or after processing) is closely related to meat tenderness, which is very important attribute for consumer. The aim of the study was to evaluate changes in microstructure of poultry meat during the chilled storage. In the study, the cross-cut microstructure of parents stock hen and broiler muscles were analyzed during the storage at + 1 +- 0.5 °C temperature. The changes were determined for the following muscles: musculus pectoralis and pars praeacetabularis musculus iliotibialis lateralis in seven hours after slaughter and on the 7th day of storage. Parents’ stock (PS) hens were slaughtered on 61st week, but broilers at the age of 42 days (on the 6th week). The decrease in area of muscle fibres of hens and broilers' musculus pectoralis was found in both types of meat when comparing the sample on 7th hour and 7th day, but the smaller decrease was observed in broilers meat. Comparing muscle fibre area of broiler and hen pars praeacetabularis musculus iliotibialis lateralis [musculus biceps femoris] in hen meat it was reduced in higher proportion, but the distance between the fibres was increased reaching similar values for both sample types.

The influence of solvent, storage time and temperature on the stability of the mycotoxin sterigmatocystin (STC) was investigated. STC calibrants (1.0 μg mlE-1) in acetonitrile, methanol and mixture of acetonitrile and methanol (50:50, volume/volume) were stored in dark glass bottles at (– 25), 4 and 25 °C for up to 8 weeks. Samples were analysed by high performance liquid chromatography (HPLC) with ultraviolet (UV) detection. Obtained results indicate that more suitable solvents for storage of STC standard solutions at (–25 °C) are acetonitrile and mixture of acetonitrile and methanol (50:50, v/v), but not longer than for one week; for storage at 4 °C more suitable is mix of acetonitrile and methanol, but not longer than for one week.

Processing and cooking methods can greatly affect the nutritional value of fruits and vegetables including potatoes. In human nutrition potatoes before consumption are always prepared by several cooking methods and are one of the central components of warm meals. During treatment processes considerable changes in nutritional composition and nutritional quality of the product are induced. Hence the aim of the study was to determine the amount of basic nutrients (carbohydrate, fat and protein) as well as essential amino acids in five Latvian potato varieties prepared by the following heat treatment methods: baking in oven, shallow frying and deep fat frying and to compare the obtained results with recommended daily intake (RDI). Achieved results show significant differences in total carbohydrate amount within potato varieties (p=0.007) while within the type of heat treatments were no significance (p=0.065). Changes in fat content between heat treatment processes were considerable (p=0.000) whereas significance were discovered between control – pan fried, control – deep fat fried, baked in oven – pan fried, baked in oven – deep fat fried as well as pan fried – deep fat fried samples while no significance found among potato varieties (p=0.391). In protein amount neither within potato varieties nor between heat treatment processes significance was discovered, but the amount of essential amino acids significantly differs per each potato variety and type of heat treatment processes. Results on RDI per each nutrient group (fat, carbohydrates and protein) show significance on % RDI per each basic nutrient.

Investigations of textural parameters of vacuum, protective gas atmosphere (MAP), and at air ambiance packed fresh carp (Cyprinus carpio L.) farmed in Latvia were carried out. The samples of carp were stored at two different temperatures (0 +- 0.5 and +4 +- 0.5 ºC) applying three different types of packaging – vacuum, MAP, and wrapping at air ambiance. Gas mixture used for MAP consisted of 40% CO2 and 60% N2. Samples were analyzed before packaging (day 0) and after 2, 4, 6, 8, 11 and 14 storage days. Textural parameters – hardness and shear force were evaluated by texture analyzer TA.XT.plus (Stable Micro System Ltd.). Two instrumental methods were applied for evaluation of textural properties. One method was based on compression test, using spherical probe, 25.4 mm in diameter (type P/1S), and measuring the hardness of the fillet and other method was based on cutting the fillet with a blade (type HDP/BSK) and measuring the shear force. The instrumental hardness and shear force of fresh carp fillets decreased during storage time. Texture variables significantly correlate with storage time, respectively, r = -0.723 and r = -0.748, the hardness and shear force. The storage time, temperature and packaging type with probability of 95 % substantially influence the textural parameters of carp fillets (P is less than 0.05).

Constructed wetland (CW) treatment systems are engineered systems designed to treat wastewater with the usage of the same processes that occur in natural wetlands. The full-scale investigations of free water flow surface filters (FWF), subsurface flow filters, including filters of vertical flow (SVF) and horizontal flow (SHF) were carried out in Lithuania. The investigations’ database collected within the study period of 1995-2007 was used for the estimation of phosphorus removal efficiency of different constructed wetlands. It was established that phosphorus removal efficiency depends on construction of filters and the load according to total phosphorus for the area unit of filter surface. Subsurface flow filters are distinguished by better phosphorus removal. At the same load of all filters, i.e., total phosphorus of 0.3 g mE-2 dE-1, the removal efficiency of subsurface flow horizontal, vertical, and free water flow filters reaches 53.0, 46.5 and 28.0%, respectively. The wastewater contains phosphorus in mineral and organic forms. Due to the aerobic conditions in filters of vertical flow, the amount of organic phosphorus removed by SVF is 3 times greater than in horizontal filters. Organic phosphorus in wastewater before the treatment by vertical filters constituted 27% of total P, and after the treatment 21%. In wastewater treated by horizontal filters this ratio was 21% and 31%, respectively.

The objective of this study was to determine the effects of topical 1% atropine sulphate and systemic atropine sulphate on intraocular pressure (IOP) and horizontal pupil diameter (HPD) in dog’s eyes. Ten adult dogs for each treatment were used in this study. Dogs of different age, breed and sex were examined clinically and ophthalmologicaly. All animals were clinically and ophthalmologically healthy. One drop of topical 1% atropine sulphate was used in ten dogs unilaterally, with the contralateral eye acting as a control. IOP and HPD were measured every 5 minutes. In ten dogs systemic atropine sulphate were used intramuscularly (IM) with IOP and HPD measured every 5 minutes. In both study phases IOP and HPD were measured over a total duration of 60 minutes. After unilateral application of topical atropine, IOP increased significantly in the treated eye. A maximum average IOP of 20.3 mmHg in the treated eye was observed 20 minutes after treatment. Maximal pupil dilatation in the treated eye was observed 35 min after treatment. Measurements made after systemic atropine showed an IOP increase in both eyes, showing maximum average IOP increase 25 minutes post-treatment. Maximum average values of HPD were obtained 25 minutes after treatment. The HPD started to decrease 30 minutes after treatment but it was still significantly higher than before treatment (P is less than 0.05). Because of atropine sulphate’s ability to cause significant increase in IOP, it should not be used for diagnosis and treatment of glaucomatous eyes.

This study was done to evaluate the prevalence and colonization density of helicobacters in the gastric mucosa of domestic dogs (Canis familiaris). Mucosal samples were taken from several places of cardiac, fundic and pyloric gland region of the stomach to detect helicobacters with urease test, brush cytology, and light histological examination. Fourteen dogs of fifteen sampled animals showed positive urease test and the presence of tightly spiraled helicobacters. Positive urease test was observed in 80.4% of all examined samples. Helicobacters were detected in 82.7% of all examined samples by brush cytology and 80.8% of all examined samples by histological examination. Compared to gastric regions, in all employed detection methods have been showed significantly higher prevalence of helicobacters in cardiac and fundic gland region than in the less effected pyloric gland region of the stomach. Histological examination showed the location and colonization density of the bacteria at the superficial epithelium, gastric pits, and deep glandular epithelium of the gastric mucosa in different regions of the stomach. Colonization density of bacteria was evaluated in 4 groups: as absent, mild, moderate, and severe colonization density of helicobacters. Occurrence of helicobacters in the cardiac and fundic gland region showed mild and moderate colonization density of helicobacters at the superficial epithelium and at the gastric pits of the gastric mucosa. Colonization density of spiral-shaped bacteria between the deep glandular epithelium was more pronounced in the pyloric gland region than in the cardiac and fundic gland regions of the gastric mucosa in the domestic dogs.

Annual judging of dairy products including sensory evaluation of local cheese-maker' cheeses proved that the quality of Latvian classical cheeses is various. In fact, in last three competitions three different manufacturers gained the first place in category of Krievijas and Holandes types' cheeses. It indicates instability of Latvian cheese quality. Two types of semi-hard cheeses (Krievijas and Holandes) were selected for testing the quality of Latvian semi-hard cheeses in the beginning of 2008. Krievijas type cheese was selected from three different manufacturers, but Holandes type cheese - from five different manufacturers. Sensory properties such as flavour, structure and colour were measured using line scale method. Statistical analysis of obtained data showed differences between such assessed properties as colour (yellowness), texture (firmness), holes, flavour (acidity and bitterness) in Krievijas type cheese, and colour (yellowness), texture (firmness), flavour (saltiness) in Holandes type cheese.

In Latvia the spontaneous sourdough is used in traditional rye bread baking whose microflora is determined in flour and in microorganism cultures presented in external environment. Almost all spontaneous sourdough cultures, especially those that have been maintained for a long time, contain both lactic acid bacteria (LAB) and yeasts. The main purpose of the current research was to analyze growth dynamics of LAB in spontaneous rye flour sourdough and to isolate some of its representatives. Experiments were carried out in the Department of Food Technology of the Faculty of Food Technology of Latvia University of Agriculture in January and February 2008. Considering differences in constituents, two types of flour were used in the research - peeled and crude rye flour. There were three stages of spontaneous sourdough preparation in 72 hours totally; the renewal of sourdough was realized each 24 hours. The dynamics of LAB plate count in every stage of fermentation was investigated as well as changes of pH was observed using standard methods. The results of experiments show substantial increase in amount of LAB in both sourdoughs, particularly in sourdough from peeled flour, reaching 6.06 log10 cfu mlE-1. A significant decrease of pH value from pH 6.7 to pH 3.8 during fermentation process was observed. As a result, the sourdough from peeled flour had desirable properties for preparation of sourdough starter. LAB cultures isolated and identified from current sourdoughs using API tests: Lactobacillus brevis and Lactobacillus fermentum are also typical members of sourdoughs found in other countries.