It is well known that secretion of gastric acid is regulated neurally by the stimulation of n.vagus and humorally by the activation of histamine H2 receptors in parietal cells. The purpose of the investigation was to clear up neural and humoral regulation mechanisms of gastric acid secretion in the postnatal ontogenesis of calves. Four calves from 5 to 14 weeks of age with chronical fistulae in abomasum have been investigated. Two electrode pH-probe has been used for measures. Atropine sulphate (0,06 mg kg*[-1) IV infusion) has been used to stop function of n.vagus, and cimetidine (0.16 mg kg*[-1) IV infusion) to block humoral regulation. The results clearly show that both, atropine sulphate and cimetidine, demonstrate some blocking influence on the HCL of abomasum in calves of different age.

The quality of forage grass mostly depends on the harvesting time. In early vegetation stages, grasses have a high protein and energy content and high dry matter digestibility. The data on the protein content and energy value of different grasses gives a possibility to choose the best conservation method. Changes in the chemical composition of perennial grasses during the vegetation were investigated at the Laboratory of Biochemistry of the LUA Research Centre "Sigra". The dynamics of the content of amino acids was evaluated.

During the last decade economy of Latvia has experienced a decrease, crises and also depression. Further development process of Latvia could lead to a rapid economical boom. The application of scientific researches into the development of nationaly economy of Latvia is one of the important aspects. Though the globalisation and commercalisation of scientific researches must be taken into account as well. Science development is opening wide range of possibilitities for research perfection. Most of the Latvian, Lithuanian and Slovakian entrepreneurs are 30-40 years old, who suddenly appeared in the circumstances of conventionally free economy in their twenties.

It is very important to use the exact investment model for energy enterprises. Giant investment is necessary for establishing continued energy systems using renewable energy resources. Demand of the heat energy usually is higher in a winter period compare to the summer time. Program combinations of different heating modus are researched using EnergyPRO.

This paper deals with the results of focus group discussions concerning the Baltic Pulp project carried out among inhabitants of Jekabpils district in February and March 2001. Group discussions were a base for qualitative analysis where differences between opinion within different social groups had been fixed. This gives an insight into opinions as well as suggestions concerning ecological, economical and social factors, connected to the planned pulp mill.