Pollution of atmosphere and decrease of fossil fuels stimulates people to search for an alternative energy sources for production of energy, both electrical and heat. In Latvia it is possible to use almost all alternative energy sources for production of energy, including solar energy that becomes more relevant year by year. Solar radiation in direct way makes no hazardous, but, as the intensity of solar radiation in geographical location of Latvia is comparatively low, the utilization of it demands relatively expensive equipment. Production of energy from other sources of energy also demands certain investments as well as the purchase of fuel, maintenance of equipment and presence of different manipulators. In practice several types of solar collector constructions with efficiency from 30 up to 75% exist and expenses vary in the wide range. The average number of sunshine hours in Latvia is about 1800 hours yearly. Nevertheless solar collectors for water heating in Latvia are used. Mostly flat-plate collectors are used whose efficiency often is not sufficient and water has to be additionally warmed-up. The aim of our investigation is to study operation of evacuated tube collector in conditions characteristic to Latvia. It is stated that it is feasible to use evacuated tube collector for water heating in Latvia, especially from March till October. During winter period solar collector can be used as additional energy source for water heating.

This paper presents results of pressure oscillation investigation in hydraulic hitch-system of a tractor Claas Ares ATX 557 during the motion during artificial roughness road test. During experiments oscillation at different driving speed, tyre pressure and hitch-system oscillation damping (turned on/off) were investigated. Tractor hydraulic hitch-system was equipped with a pressure sensor Wika Transmitter ECO-1 and data processing software PicoLog. Results of experiments present maximum pressure peak of 210 bar in the tractor hydraulic system when hydraulic hitch-system oscillation damping system at driving speed 8 km·hE-1 is not used and system pressure peak reduces to value of 180 bar if the hydraulic hitch-system oscillation damping is used.

Dairy ecosystems have been developing in thousands of years giving us wonderful collection of different types of cheese varieties. On the other hand, modern technology provokes the loss of variability (Adamberg et al., 2007). The only way to keep biological processes under control is to study physiology of microorganisms, and relationships between them systematically, especially non-starter lactic acid bacteria (NSLAB). The number of non-starter lactic acid bacteria increases during cheese ripening and may constitute a dominant population in the mature cheese. The NSLAB diversity, their metabolism and interactions with starter bacteria have an effect on the ripening process of the cheese. The aim of the present study was to investigate the diversity of Lactobacillus spp. during ripening of Krievijas cheese. The diversity of different profiles varied among the cheese samples matured at different temperatures, and the results indicated a correlation between NSLAB species and aroma development (Miķelsone et al., 2009). A higher metabolism of Lactobacillus curvatus at 12 deg C leads to faster depletion of nutrients and approaching the last two phases of microorganism growth curve. However, in each of the cheeses, the microflora had a tendency to be dominated by one Lactobacillus profile at the end of maturation.

The aim of the study was to find out the differences of blood biochemical and morphological parameters in cows with and without retained foetal membranes. Sixty cows of different age of Latvian blackand- white breed from two Joint Stock Companies were used in the research that was divided into two groups: control group of 15 cows, and 45 cows with retained foetal membranes. Research was done from September 2007 to January 2009. In haematological parameters on the second day postpartum, control group cows had increased leukocyte count on the account of mature neutrophils, but in the group of cows with retained foetal membranes leukocytes were within the range of normal values. The difference of the above mentioned parameters between both of the groups was significant (p is less than 0.05). At the same time, in cows of both investigated groups the number of band neutrophils was slightly increased (p is greater than 0.05). Haematological analyses showed leukocytes shift to the left and lymphopenia with a tendency to get normal within six weeks postpartum in both cow groups. On the third week postpartum, in cows with retained foetal membranes the band neutrophil count increased significantly (p is less than 0.05) indicating that the inflammation process has flared up. Blood for biochemical examination was sampled from cows within 48 hours postpartum in order to evaluate the functional condition of liver in milking cows. A significantly higher (p is less than 0.05) total and direct reacting bilirubin was observed in cows with retained foetal membranes, although it was within the range of normal values.

Reduced fertility associated with fluid accumulation has been recognized for many years in broodmares. Fluid present in the uterus after ovulation is often associated with mare susceptibility to endometritis. Objective of this study was to determine amount of intrauterine fluid secretion and endometrial oedema in mares at the time of artificial insemination (AI), 6 h, 25 h, and 48 h after AI and at the time of ovulation. A total of 22 cycling light breed mares from MTT Agrifood Research, Ypaja, Finland, were used in the study. Relaxation of the cervix, the number and size of follicles, corpus luteum, and the degree of endometrial oedema were examined by transrectal palpation and ultrasonography every other day. According to the closing and opening time of the cervix which was regulated using Bivona catheter, mares were distributed into 3groups. Group A (n=7): immediately after artificial insemination (AI) the catheter was inserted into the uterus. After 25 h, the catheter was opened and the fluid drained. Group B (n=8): immediately after AI, Bivona catheter was inserted into the uterus. After 6 h and 25 h the catheter was opened and the fluid drained. Group C (n=7)-control group: no catheter was inserted into the uterus. According to our investigation, we concluded that the amount of intrauterine fluid accumulation (IUFA) in mares increased within 25 h after AI. Mares with delayed uterine clearance had a significantly larger amount of intrauterine fluid than mares with normal uterine clearance. Open cervix during oestrus period is important for adequate clearance of intrauterine fluid in mares. Opening of intrauterine catheter at 6 h post AI didn’t diminish intrauterine fluid accumulation at 25 h post AI.

There are several unique features in the anatomy of the stomach in African ostrich in comparison with other birds. The goal of this study was to determine changes in the main morphometric parameters and histological features of gastric mucosa in ostrich chickens from the 38th day of embryonal development until 60 days of age. For the study, 6 embryos (38th day of development) and 36 chicks (1, 3, 7, 14, 30, and 60 days post hatching; 6 chicks per time point) of both sexes were obtained from African ostrich farm in Latvia during May - October, 2009. Tissue samples were investigated in Preclinical Department, Faculty of Veterinary Medicine. The total area of proventricular mucosa (cm2) and surface area of deep glands (cm2) was measured. Tissue sections for histological assessment were stained with: hematoxylin and eosin and alcian-blue pH 2.5 - periodic acid – Schiff reaction. Thickness of proventricular and ventricular mucosa, depth of proventricular superficial glands as well as surface area of parenchyma occupied by deep glands were measured in histologic sections. As the chick age increased, there were changes in the ratio of areas occupied by proventricular superficial and deep glands with relative decrease in area occupied by deep glands. Proventricular deep glands developed rapidly after hatching; at the age of 30 days deep glands histologically resembled glandular structure of adult birds. Gastric mucosal epithelial cells of 38 days old ostrich embryos and of just hatched ostrich chicks contained neutral, acidic, and mixed mucopolysaccharides. Meanwhile, in the pyloric region of ventriculus acidic mucopolysaccharides predominated.

The aim of the work is to investigate raw milk from different bulls' daughters to clear up the influence of cows' genetic predisposition to milk microbial contamination and somatic cell count (SCC). Particular attention is paid to develop productive cow milk yield, milk fat, milk protein and in recent years, the SCC heredity. The literature describes a variety of lines and families, representatives of the resistance to certain diseases (leucosis, mastitis, tuberculosis, brucellosis, foot disease), it shows the determination of a genetic factor for this trait. If the selection results show increased resistance to a disease, then this indicates a genetic disease resistance and shy. The paper focuses on microbial contamination of raw milk at 7 different studies of bull daughters in the same line for housing, feeding and conditions of use. Raw milk samples were obtained from the breed Latvian brown (LB) from dairy cows shed of cattle shed Saujas, which belongs to SIA Palsa and is located in the civil parish Varini, Smiltene county in the year 2008/2009. Compared between the lines of bulls' daughter milk yield of the sample average value of the uniformity of variance analysis shows that they significantly differ (F=2.452, p=0.039). Comparing each line of bulls' daughters SCC of the sample average value of the uniformity of variance analysis showed that the SCC was statistically significantly different (F=2.083, p=0.075) of the various lines of bulls daughters.

Systemic view on tourism as an economic activity is the best way how to characterise an economic nature of this industry. The paper presents the methodology which integrates the system approach and other research methods of social sciences; this methodology forms the basis for identification of social agents and models of tourism system. The methodology is approbated in the survey of providers of rural tourism services in Zemgale planning region. The research results are useful in future application of models for development of tourism whereas the models are useful for other purposes: they can provide additional information necessary for evaluation of tourism influence on economy. They form a basis for detecting participants in tourism clusters in regions and for evaluation of cooperation between social agents of public, nongovernmental and private sectors, and as an instrument in tourism marketing strategies.

The production of innovative composition (high omega group fatty acids and antioxidants-carotenoids) broiler chicken meat and egg opportunities in Latvia was assessed. After feeding the poultry with feed enriched with fatty acids and antioxidants, broiler meat and eggs of innovative composition containing a higher amount of omega-3 (in meat by 1.7%, in eggs by 2.7%), omega-6 (in meat by 3.9%, in eggs by 3.2%) and carotenoids (0.44 mg kg-1 in meat and in eggs by 6.9 mg kg-1) when compared with the content of commercial products are obtained. Nutrition costs of innovative composition-based broiler chicken meat production are LVL 20 higher and nutrition costs of egg production are LVL 1.49 higher per 1000 units of output than in the standard version of the poultry feeding-stuff. The poultry farming production of an innovative composition, however, is economically profitable due to the higher rates of poultry productivity. In the case of an innovative composition-based yield the potential profit at the currently equal cost realisation of poultry meat and eggs is higher when calculating 293.47 LVL per 1000 broiler chickens and 5.52 LVL per 1000 eggs in comparison with commercial production.