The contents of ascorbic acid (AA) and its oxidized form, dehydroascorbic acid (DHA), were assessed as related to the tracheid differentiation in the course of early and late wood development in the Siberian larch ( Larix sibirica Ldb.) trees. The samples of the cambium, cell enlargement zone and mature cells were collected at the successive developmental stages by scraping tissues off layer by layer from trunk segments of the 20-year-old trees according to anatomical and histochemical criteria. While cambium initials were rapidly dividing, the AA contents per dry weight and per cell considerably exceeded the corresponding values characteristic of the late xylem development; such difference corresponded to the higher number of early tracheids per annual ring, as compared to the late tracheids. The AA content decreased as cells enlarged. The radial growth of the early wood tracheids, as compared to the late wood tracheids, was accompanied with a threefold increase in the AA and a decline in the DHA contents. The AA/DHA ratio was in line with the early tracheid enlargement. The maximum AA content was observed at the early stage of the secondary cell wall thickening in the tracheids of early and late xylem preceding lignification. During this stage of early wood development, the DHA content exceeded sixfold the corresponding value in the late xylem; as a result, the initial rates of lignification were different in two tissues. The rate of lignification in a newly developing layer of the early xylem increased gradually and was the highest in the completely differentiated tracheids. In the late xylem, the lignification rate was at its highest at the very beginning and then declined in the course of tracheid maturation. The dissimilar patterns of lignification in the early and late xylem were primarily associated with the DHA content, which increased in the early xylem and decreased in the maturing late xylem. Thus, the AA content and its accessibility to oxidation in the growing and mature xylem cells exhibited the diverse developmental patterns in the early and late xylem: two tissues differed in the tracheid number and radial diameter as well as in the rate of lignification. Key words: Larix sibirica -development of early and late xylem -cambium zone -cell enlargement zone -zone of the secondary cell wall deposition and lignification -ascorbic acid -dehydroascorbic acidAbbreviations : AA-ascorbic acid; CEZ-cell enlargement zone; CZ-cambium zone; DHA-dehydroascorbic acid; MXmature xylem; MZ-maturation zone (zone of the secondary cell wall deposition and lignification).

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The optimal combination of seed sprouting and extrusion processes reduces the energy, economic and labor costs of germination and decreases the loss of sprouted seed. To obtain sprouted seed, various pre-treatment methods were evaluated before the extrusion process. It was found that the optimal pre-treatment of seeds before sprouting is treatment with microwave radiation of 1400 W/dm3 for 20 s or 3% hydrogen peroxide for 10 min. When using such treatment methods, not only microflora suppression but also activation of the feed seed sprouting process are provided. The first sprouts appear in 12 hours. In 60 hours, the amount of sprouted seeds reaches 70-90 %. The length of sprouts at this stage of germination is optimal for further processing and is from 5 to 25 mm.

The use of local raw materials in the mixed fodder formulations for broiler chickens, including non-traditional raw materials, allows to expand the range of manufactured feeds possessing high nutritional properties and biological value. In order to improve the quality and to reduce the production costs of the mixed fodder due to the cheap raw materials use and the reduction of the premix use share, the mixed fodder formulation for broiler chickens was developed. The nutritional and energy value, safety of mixed fodder are determined. It is established that the nutritional and energy value of the mixed fodder with extruded mixture of non-crushed wheat, peat and cones meets the requirements of the current standard for complete feed for poultry and is obtained in accordance with the rules of the production technological process organization and supervision in the mixed fodder industry. The obtained mixed fodder with the use of non-traditional additives is non-toxic. There is no pathogenic microflora. Replacement of the expensive premix with peat, cones and introduction of non-crushed wheat grain into the mixture before extrusion helps to reduce the cost of finished products. In the production of extrudate from non-crushed wheat (98.8 %), peat (0.6 %) and cones (0.6 %), grinding and mixing with other components of the mixed fodder, the proportion of premix P5-1 decreased to 0.52%. The mixed fodder quality improvement is due to the enrichment with vitamins, essential amino acids and vegetable protein by adding cones and peat.

Carrying out researches on extrusion of grain crops with inclusion of vegetable components and assessment of their energy value and competitiveness is an important task. Due to this quality indicator of the ekstrudat on the basis of wheat, barley, oats with inclusion of pulp of green grasses have been defined, the assessment of energy return and energy efficiency ratio has been carried out. The energy value of grain crops increased after extruding by 8.33 – 10.86%. The pulp of green grasses was mixed with seed of wheat or barley or oats in number of 10, 15 and 20% of the mass of mix. After mechanical dehydration of a grass mix the energy value of pulp was 10.68 MDzh/kg. At joint extruding of grain crops with pulp from a grass mix the power value of the ekstrudat decreased and was 0.12-0.21 MDzh/kg. Reduction of power value of the ekstrudat leads to decrease in power return by 0.12-0.21 MDzh/kg. At the same time the energy efficiency ratio is increased by 5.44-6.4%. Increase in power efficiency ratio is connected with reduction of energy input on grain crushing. Extrudat on the basis of wheat mix and 20% of pulp corresponded to the greatest value of energy return and energy efficiency ratio. The equations of linear regression have been received for the mathematical description of change of energy return and energy efficiency ratio. Use of pulp as a part of mix before extruding allows to receive a ready-made product with lower cost price in connection with reduction of grain mass as a part of the ekstrudat.