2008 * XIX * 2

V. Eremeev, P. Lääniste, E. Mäeorg, J. Jõudu.  
  Mugulate arvu kujunemise dünaamika sõltuvalt seemnekartuli termilisest töötlemisest 3
The dynamics of formation of tubers depending on the thermal treatment of seed potato. Thermal shock and pre-sprouting increased the formation of tubers per plant, particularly at the beginning of tuber formation until 60 day after planting, whereas the maximum number of tubers was formed at 93–94 day after planting (12.6 and 14.0 tubers, respectively). In untreated variant, the respective value was 13.2 and it formed at 95 day after planting.Pre-sprouting increased the number of tubers with the cultivar ‘Piret’ and only at the beginning of tuber initation. Throughout the entire vegetation period the number of tubers of the cultivar ‘Ants’ was higher due to the thermal shock treatment then in other variants, in the cultivars ‘Piret’ and ‘Varajane kollane’, until 50 day after planting and 60 day after planting, respectively.The cultivars‘Piret’ and ‘Varajane kollane’ started to form tubers early but had a lower average numbers of tubers per plant compared to ‘Ants’. In ‘Varajane kollane’ the maximum number of tubers was formed at 92 day after planting (12.8 tubers), in ‘Ants’ (14.6 tubers) and ‘Piret’ (12.1 tubers), respectively, at 93 and 97 day after planting.
Keywords: pre-sprouting, thermal shock, cultivar
H. Jirgena, J. Vanags.  
  Theoretical aspects of farm diversification 10
Theoretical aspects of farm diversification. There are situations in agricultural production when one or several production factors have to be involved in production of different goods and not infrequently such a situation develops when the number and quality of production factors do not correspond to the production goal. This is shown by large areas of unused agricultural land, continuous unemployment in many rural regions and a low income level. In free market economies, production methods or the type of services provided are determined by those who utilize the limited resources in the most effective way. The paper deals with effecency determination of the existing resources and the need for a justified production diversification upon applying the law of diminishing returns. The research includes models on production diversification possibilities within and outside the industry of agriculture. The calculations revealed a potential effect of diversification of labour force and land use in Latvian regions.
Keywords: diversification, economic effecency, resources, production, costs
H. Kaldmäe, H. Suurmets, T. Järveots, T. Suuroja, O. Kärt.  
  Effects of supplemental yeast (Saccharomyces cerevisiae) culture on rumen development and growth in calves 19
Effects of supplemental yeast (SACCHAROMYCES CEREVISIAE) culture on rumen development and growth in calves. Yeast culture (Saccharomyces cerevisiae) was added to a calf starter at 0 (control), or 2% of dry matter to determine effects on intake, growth, and rumen development. Twenty Estonian Holstein calves (12 male and 8 female) were involved in the experiment at 5 days of age. Texturized calf starter and hay were offered ad libidum, and intake was measured daily. A subset of male calves was euthanized at 35 d of age and the other at 65 days of age for rumen epithelial growth measurements. Average final body weight of the control group was 90.59 kg, and that of the 2YC group 90.60 kg, the average daily gain of the control group during the first month was 384 g and that of 2YC group 348 g; during the second month it was 994 g and 1033 g, respectively. In the first month the dry matter intake of the control group was 1.25 kg/d and that of 2YC 1.22 kg/d, respectively, and in the second month 2.29 kg/d and 2.33 kg/d, respectively. It was not significantly affected by yeast supplementation in the starter ration. Supplemental live yeast culture in the calf starter did not increase dry matter intake of the calves in the two first months of life. In the second month of life, yeast supplementation slightly increased the daily gain of 2YC group and improved the usage of metabolizable protein, as compared to the control group. The results indicate that calves receiving supplemental yeast (Saccharomyces cerevisiae) culture exhibited a slight improvement in rumen development parameters.
Keywords: yeast culture, rumen development, intake, calf
R. Kõlli, T. Köster, O. Ellermäe.    
  Mullateaduslikud kogud 24
Scientific collections of soils. In the current work the problems connected with establishment of soil monoliths collection or soil museum and connected with this different other kind collections are treated. The scientific collections play important role at least from the three aspect: history of science, teaching of students and enhancing awareness of society. In actual work the concerned to scientific collections problems are treated on the base of corresponding material retained in the Department of Soil Science and Agrochemistry of Estonian University of Life Sciences. The list of scientific collections conserved in the department is following: (1) collection soil monoliths; (2) paintings characterizing soil regions; (3) formerly used fertilizers; (4) soil maps; (5) academic documents (dissertations, annual and project final reports, manuscripts and other); (6) collections of minerals, soil parent materials and local basements sediments; (7) soil samples of soil monitoring; (8) soil samples taken from long term field experiments, permanent research areas and transects, and (9) valuable exhibits (photos, facilities and others) needing cataloguing and conservation. In the soil museum 133 monoliths are exposed and ca 20 monoliths are in reserve. On the name plate of soil monoliths the Estonian soil names are converted into systems of World Reference Base for Soil Resources (WRB), of United States Department of Agriculture Soil Taxonomy (USDA) and into Russian Soil Classification (RSC). For characterizing soil monoliths collection one booklet and special CD are published. The problems aroused with taking and preparation soil monoliths are treated in the work as well. It concluded that much more attention must be paid to preparation digital photos not only on soil profiles and soil forming conditions, but also on forest and grasslands humus profiles. In last three parts of paper the future development are discussed. As in nearest future the management of all scientific collections will be done jointly, is important to expose soil monoliths in mutual relationships with other natural exhibits. Fully realistic is it in the case of digital approach, but rather expensive by using natural exhibits. The good side of joint management is collaboration in preparation, conservation, presentation and cataloguing of exhibits. It is emphasised the importance of using bilingual approach (Estonian and English), which is good base for international collaboration.
Keywords: awareness of society, soil science, soil collections, soil monoliths, paintings, museum
R. Lauk, E. Lauk, Ü. Lauk. 32
  Suviviki kasvatamine koos nisu ja kaeraga: seemnesaakidest ja proteiinisaakidest  
Intercropping common vetch with wheat and oats: about seed yields and protein yields. This study was conducted in the trial fields of the Estonian University of Life Sciences outside Tartu, Estonia, on a pseudopodzolic moderately moist soil. The study, performed over three years (2000–2002), showed that the inclusion of vetch seed in cereal seed and the increasing of its seed density led to considerable decrease in the yield of the cereal component (R = 0.980–0.998). The adverse effect of vetch on cereal yield led to a reduction in wheat yield by up to 1,861 kg ha–1 on average for the three years, and in oats yield by up to 1,413 kg ha–1. The maximum protein yield per area unit in cereals was obtained from their sole crops, and their protein yield per area unit reduced at higher vetch seed densities. Vetch-cereal mixes had an advantage over cereal monocultures insofar as protein yield was concerned. In vetch-wheat and vetch-oats mixes the maximum protein yield was 500 kg ha–1 and 438 kg ha–1 respectively on average for the three years. Vetch-cereal mixes are particularly suitable for the conditions of organic farming, and should be recommended to farmers, as they ensure a relatively good harvest and high protein yield on soil without nitrogen fertilizers.
Keywords: Cereals, vetch, intercrops, seed, yield, protein
H. Lõiveke, E. Ilumäe, E. Akk.
  Teravilja mikrobioloogiast ja ohutusest 38
Microbiology and safety of grain. The present paper offers an overview of studies in grain safety and microbiology carried out at the Estonian Research Institute of Agriculture since 1973. Main genuses and species of grain-infecting mould fungi as well as their potential toxicity have been studied using Bacillus stearothermophilus biotest. Data about grain mycotoxin monitoring are displayed since 1998. The presence of T-2 and HT-2 toxins in Estonian grain was proved for the first time in the grain yield from 2006. The dangers arising from mould fungi and of mycotoxins they produce as well as ways to avoid these threats are discussed.
Keywords: grain, microbiology, safety, mycotoxins
I. Sematovica, M. Pilmane, A. Jemeljanovs.
  Investigate vascular endothelial growth factor, nerve growth factor receptors p75, protein gene product 9.5, tumor necrosis factor–α and apoptosis in the cow endometrium in post partum period 46
Vascular endothelial growth factor, nerve growth factor receptor p75, protein gene product 9.5, tumor necrosis factor-α and apoptosis in the cow endometrium in post partum period. Biopsy samples from cows uterus were taken in winter 2004/2005 on the research and training farm “Vecauce”. Histological investigations were performed at the Institute of Anatomy and Anthropology of Riga Stradins University. Nine cows were biopsied twice – in the first and fifth week after parturition. The aim of the work was to investigate vascular endothelial growth factor (VEGF), nerve growth factor receptors p75 (NGFR p75), protein gene product 9.5 (PGP 9.5), tumor necrosis factor α (TNF–α), and apoptosis in the cow endometrium in post partum period.
The results showed a significant increase of VEGF, NGFR p75, TNF–α amount, and the number of apoptotic cells in the cow endometrium between the first and the fifth week after parturition (p<0.05). VEGF expression in the cow endometrium was found in the fifth week after parturition, mainly localized in blood vessels. A close positive correlation (r=0.72; p<0.001) was found between VEGF and TNF–α, as well as between VEGF and NGFR p75 (r=0.64; p<0.05) expression in the cow endometrium at that time of post partum period. NGFR p75 were localized in the nerves around endometrial glands, blood vessels and under epithelium. A mild positive correlation (r=0.51; p<0.05) was found between the expression of NGFR p75 and TNF–α in that period. The amount of TNF–α showed a mild positive correlation (r=0.59; p<0.05) with a number of apoptotic cells in the cow endometrium in post partum period, as well as a significant mild positive correlation (r=0.59; p<0.05) was found between the amount of apoptotic cells and expression of VEGF in the cow endometrium. PGP 9.5 was found in nerves of the walls of endometrial glands, under epithelium and in the walls of blood vessels. A mild positive correlation was found in the cow endometrium between PGP 9.5 and NGFR p75 expression from the first to the fifth week after parturition. In conclusion, the increase of NGFR p75, VEGF and TNF–α expression in the cow endometrium from the first up to the fifth week after parturition seems to correlate with the ischaemia of tissue increased by inflammatory action. The latter also seems to stimulate the apoptosis and proliferation of nerve fibres in the cow endometrium.
Keywords: cow endometrium, post partum, vascular endothelial growth factor, nerve growth factor receptors p75, protein gene product 9.5, tumor necrosis factor–α
S. Tölp, E. Rihma, O. Kärt, H. Kalamees.
  Lüpsilehmade söötmise ja grupeerimise strateegiate valikutest vabapidamisega farmides 51
Feeding and grouping strategies of dairy cows on farms with loose housing system. The study was aimed at finding the principles of grouping dairy cows in loose housing barns of different size, and comparing feed use efficiency in milk production. The investigation was carried out on two large-scale farms – F-1000 (~1000 dairy cows) and F-600 (~600 dairy cows), and on two small farms – F-350 (~350 dairy cows) and F-200 (~200 dairy cows). On all investigated farms feed consumption and milk production were monitored using the same methods. Feed samples collected from the farms were analysed at the chemistry laboratory of the feeding department of the IVMAS of the Estonian University of Life Sciences.
The cows were fed total mixed rations (TMR). When using the TMR method of feeding cattle, grouping of cows plays an important role. On the above mentioned farms the feeding groups were formed according to the stage of lactation and milk production. Feeding schemes with different number of feeding groups and different concentration of nutritional factors were used. Grouping of cows was influenced by the herd size and homogeneity, and also by housing facilities.
For estimating the feed use efficiency, the data collected from three farms – F-1000, F-600 and F-200 – were analysed. The highest daily milk production per cow was recorded on F-1000. On that farm the use of many feeding groups enabled to meet the cows’ nutritional requirements and due to that the use of metabolizable energy and concentrates for milk production was the lowest.
Generalising the research results and data found in the literature it can be claimed that on large-scale farms it is reasonable to form as many feeding groups as possible. In very homogenous herds the cows may be grouped into a few feeding groups only.
In order to give final recommendations for feeding management in loose-housing systems, it is intended to analyse the change of body condition scores through the lactation cycle, metabolic disorders in cows, fertility parameters as well as economic profitability of milk production.
Keywords: total mixed ration, feeding group, concentration of nutritional factors, metabolizable energy, feed use efficiency.