In majority of cases, a positive effect can be observed upon application of Laser Agnis-L01 in treatment regimen of bone fractures. Positive effect of the laser was observed in 66.7%, no change in 22.2% and negative effect in 11.1% of the rabbits in experiment. To accelerate healing of bone fractures, we recommended the following parameters in treatment regimen with Agnis L01: impulse power 1.5 W, impulse frequency 250 Hz, modulation frequency 50 Hz and duration of treatment episode 240 seconds, 5 squares of treatment, 1 dosage per day, 10 treatment episodes. The treatment should start from day 4 after occurrence of fracture. Efficacy of laser treatment depends on individual properties of animal. Treatment of bone fractures is complex, laser treatment could be an element of the treatment regimen.

There are five programming regions and regional development agencies. Regional development agencies must be involved in the administration process of the EU's prestructural funds. Research is done using Richard Rhod's classification of regions and the experience and practice of Great Britain in specially supported regions. The program of specially supported areas is the main financial instrument in Latvia, which promotes territorial development in depressive regions. The administrative territorial reform will make rectification in specially supported areas and in planning regions.

After regaining independence the agricultural production in Estonia has undergone a drastic decline. Due to the inadequate application of fertilizers and pesticides, the yield of field crops and grasslands has decreased 1-7 % per year. The balance of nitrogen in the arable soils is negative, particularly respecting fodder crops. At present, in Estonia most of grasslands are practically not fertilized, or they are fertilized in the last order. The amount of nitrogen removed with the yield of fodder crops, cereals and potato are by 45, 20 and 17 kg ha*[-1) higher, respectively, compared with the amounts of N applied to the soil with organic and mineral fertilizers, available for those crops. The effectiveness of nitrogen fertilizers depends largely on weather conditions during the vegetation period and is the lower, the higher is soil humus content. On gleyic and gley soils, whose humus content is higher, the efficiency of nitrogen fertilizers is 2-3 times lower and the agroecological and economic fertilization risks are higher. On sown grasslands, the efficiency of nitrogen fertilizers depends not so much on soil fertility as on soil water supply, humus content and grass sward type. With proper application of fertilizers, use of suitable plant species and varieties, it is possible to increase significantly not only the yield per unit area but also its nutritive value.

Production of cereals is mostly processed by operating the machinery. Operation of machinery influences the yield, i.e. also the income on one side, but it is also one of the biggest sources of expenses from the other side. Increasing the yearly operation time and amount of work of the machinery leads to decreasing costs per unit. Increasing the yearly amount of work is limited by agrotechnical terms. The crop yield depends on the time and duration of field work, and affects the farm income. The methods and formulae to prognosticate the averageoptimum yearly operation time of farm's machinery, i.e. also farm's cereal-growing area was composed by the author, concerning biological, technical and economical factors and relations, affecting cereal production. Farm profit and profitability were used as optimization criteria.

The aim of the present research was to determine the level of cholesterol in the milk of the Latvian cow herds and to find out the effect of the milk fat content on the cholesterol level. Milk samples were obtained from the cows of Latvian Brown and Black and White breeds during the morning and afternoon milking. The milk fat and protein were analysed by Milkscan 133, cholesterol content was determined by spectrophotometer CF 26 LOMO. The average milk fat content was 4,45% and average cholesterol content - 20,94 mg 100 ml*[-1). It was found that the cholesterol content in milk was consistently higher to cows the milk of which had a higher fat content and the cholesterol content was different in the morning and afternoon milking.

The aim of research was to analyse the spread of goats eimeriosis in Latvia, determine the structure of eimeria species as well as the efficiency of treatment of goats eimeriosis. Coprological examination of goats, carried out with Fileborn method, showed that the average level of eimeriosis influence on goats was about 25.2% and 3 dominant species of emeria such as E.arloingi, E.ninakohlyakimovae and E.alijevi. The highest level of influence was discovered to animals under 1 year of age, as with E.ninakohlyakimovae (62.5%) as the dominant specie, to animal above 1 year of age - E.arloingi (57.3%-66.7%), respectively. As the result, such preparations as sulfadimetoxine in dosage 75 mg kg*[-1) amprolsol 50 mg kg*[-1) showed high level (about 91%) of efficiency of emeriosis treatment.

The epidemiology of barley yellow dwarf disease is highly complex, involving numerous interactions between the abiotic environment and the crop, virus and vector - components of the disease. Barley yellow dwarf is the most economically damaging virus disease of grass and cereal crops worldwide. The disease identified as BYD has been reported in all countries in Europe causing losses on barley and oats, wheat and maize; losses on grasses are recognized but more difficult to quantify. There are five different strains of viruses causing BYD disease and all of them induce similar symptoms of chlorosis and stunting in graminaceous hosts. This report represents an overview of system components and their interactions in the epidemiology of barley yellow dwarf disease. As the main components considered here are aphids - (the only vectors of these viruses), host plants and viruses causing BYD disease. Some aspects of interactions between these components are also discussed.

The effect of different fertilizer backgrounds on the potato yield and its chemical composition of different varieties, destined for processing into chips, was investigated at the Elmininkai Research Station of the Lithuanian Institute of Agriculture in 2000. The investigation showed, that potato tuber yield depended on fertilization and genetic characteristics of the potato variety. The most productive potatoes of the following varieties were: early Voke (20,6-36,0) t ha*[-1) and medium late Saturna (27,0-35,4 t ha*[-1)).

One of the main preconditions for an economical milk production is a balanced cow feeding that contains high quality grass forage. Chemical composition of cocksfoot forage during vegetation was investigated at the Research Centre "Sigra" in the Biochemical laboratory of the Latvia University of Agriculture. Changes in the content of crude protein, NEL MJ kg*[-1) of DM, NDF, ADF and DM digestibility were determined. The chemical composition of grass forage depends on many factors, the most significant of which is the harwesting time. The feeding value of the cocksfoot grass decreases during its growing stages as the content of fibre increases and becomes lignified.