2002 * XIII * 5

M. Järvan, T. Paide, A. Soasepp, T. Valgus.  
  Effect of liquid nitrogen fertilizer and rare earths on spring wheat 261
Effect of liquid nitrogen fertilizer and rare earths on spring wheat. On the basis of nitrogen-rich production residues AS Silmet, which is on the second place in the world as to its production volume of rare earths, has since 2001 been providing agriculture with liquid nitrogen fertilizer.

The aim of this work was to investigate the effect of above mentioned fertilizer and rare earth solution on spring wheat. The field trials at the two places were carried out.

The liquid fertilizer applied by spring cultivation at the rate of N60 kg/ha (300 l/ha) increased the yield of spring wheat, depending on the place of growth and variety, by 0.82 and 1.02 t/ha, i.e. 20.0 and 28.5%. N90 kg/ha (450 l/ha) applied as liquid fertilizer increased the yield by 0.94 and 1.67 t/ha, i.e. 23.1 and 46.7%.

Comparing the efficiency of liquid fertilizer and granulated ammonium salpetre at the fertilization level of N60 kg/ha on the basis of average sales prices and agent contents of fertilizers, the extra yield of wheat per 1 EEK spent for purchase of fertilizer was in the case of liquid fertilizer 4.6–5.8 kg and in the case of ammonium salpetre 2.9–3.8 kg.

Application of rare earths at the rate of ΣR2O3 0.5 and 1.0 kg/ha to liquid fertilizer by spring cultivation increased the yield of wheat by 0.15 and 0.31 t/ha.

Application of rare earths at the rate of ΣR2O3 228 g/ha to herbicide solution in weed control increased the yield of wheat by 0.63 t/ha, i.e. 14.0%.

In order to identify the optimum liquid fertilizer application times and rates on cereals during growth and to combine fertilizing with other treatments, further studies are necessary.

AS Silmet’s liquid fertilizer is an effective nitrogen fertilizer, which is suitable for use on cereal and other crops. Its economic profitability depends considerably on transport costs, the availability and cost of fertilization equipment, and other factors, which should more precisely be estimated by the user of fertilizer.

Keywords: N fertilizers, liquid fertilizer, rare earths, spring wheat, yield, protein content.

T. Järvis, I. Miller.  
  Trichinella infection in animals and humans in Estonia 266
Trichinella infection in animals and humans in Estonia. Trichinella infection is widespread in wild animals in Estonia. The prevalence of infection ranged from 1.0% to 80.5% for sylvatic animals and from 0.6% to 24.5% for domestic and synanthropic animals and for farmed fur-animals. The most important reservoirs of Trichinella in nature were raccoon dogs, red foxes, lynxes and wolves. Rare cases of pig trichinellosis are registered. T. nativa, T. britovi and T. spiralis were detected in animals.

Relatively few cases of human clinical trichinellosis occur. The regulation of trichinellosis control in Estonia is strict, but problems due to human improper behaviour occur in its fulfilling.

Keywords: Trichinella spp, wild animals, domestic animals, farm fur-animals, rats, man, prevalence of infection, intensity of infection.

A. Kaasik, H. Kask, E. Pedak.  
  The influence of different treatments on the degradability of dry matter and protein (some of the amino acids) in cereals 271
The influence of different treatments on the degradability of dry matter and protein (some of the amino acids) in cereals. The effect of mechanical (milling, crushing), thermal (120 °C, 15 min.) and chemical (NaOH, 3,4125 n) treatment on the nutrient degradability of wheat, barley, oats and rye in the rumen of cattle was studied. Dry matter, protein and amino acid solubility and degradability in rumen was most influenced by mechanical treatment, particle size of the meal fraction (meal, flakes) and by cereal specific weight. The nutrients in large-fractional milling products with higher specific weight were solved and degraded slower and to a lesser extent. Decreasing fractional size of the product was associated with increasing rumen solubility and degradability of the nutrients. The correlation between the type of mechanical treatment (fractional composition) and the time and extent of nutrient degradability and solubility decreased when cereal specific weight was decreasing. Short thermal treatment did not influence the speed and extent of dry matter degradability of crushed cereals, while effective degradability of protein and amino acids was decreased to some extent. Dehulling the untreated cereal grain by NaOH increased the speed and extent of nutrient degradability.

Keywords: milling, crushing, heat treatment, NaOH treatment, degradability, protein, dry matter, lysine, arginine, histidine, rumen, cereals.

J. Kanger, H. Kärblane, L. Kevvai, A. Püssa.  
  Influence of fertilization to the soil's humus content 287
Influence of fertilization to the soil’s humus content. The trial was carried out on the podzolic sandy loam (pHKCl 6.2–6.5 and the content of humus 1.52–1.60%) in Antsla Experimental Station. The depth of the ploughing layer was 32 cm. The concentration of plant nutrient was 49–72 mg kg-1 of P and 145–175 of K in the ploughing layer. The trial prolonged 2 rotations (12 years) and the rotation fields were potato, late barley, early barley (timothy under sown), timothy (2 years), and winter rye. The changes in soil’s humus content were investigated on 2 backgrounds: non-fertilized and fertilized with mineral fertilizers. Solid manure was applied once in the rotation in dozes of 30, 60 and 90 t ha-1. The balance of soil humus was found by methods based on soil analyses and calculations.

It was found out that the changes in soil humus content depended also on fertilizers applied. The humus content decreased 0.015% per years on non-fertilized plots. In the rotation of 50% of grain crops, 33% of timothy and 17% of potato the application of mineral fertilizers in the rate of 95 kg ha-1 of N, 28,3 kg ha-1 of P and 74,2 kg ha-1 of K on the average per year or manure in the rate of 15 t ha-1 per year guarantied the equilibrium of humus balance in the soil. The lower rates of application of manure (5–10 t ha-1 per year) didn’t guarantee the equilibrium of humus balance in the soil.

Keywords: soil humus, mineral fertilizers, manure, crop rotation, humus balance.

M. Noormets, K. Karp, M. Starast, T. Paal.  
  The influence of fertilization on the production of lowbush blueberry (Vaccinium angustifolium Ait.) seedlings on opencast peat pits 293
The influence of fertilization on the production of lowbush blueberry (Vaccinium angustifo-lium Ait.) seedlings on opencast peat pits. A study for the examination of the influence of top dressing and foliar fertilizers on the production of lowbush blueberry (Vaccinium angustifolium Ait.) seedlings was conducted at the county of Tartu, southern part of Estonia. Top-dressings were applied in spring (middle of May) at one main rate of 300 kg ha-1, and foliar fertilizer was applied in the form of 0.5% solution in early summer (beginning of June) 1999. There were used two combined fertilizers Kemira PK (0:12:18) and Rekle NKP (10:20:20 + micro-elements) and an nitrate based foliar fertilizer (N15.5%, Ca 19%). The three-year study was carried out in an opencast peat pit field on Fibric-dystric Histosol according to WBR classification. The influence of fertilization on the production of seedlings was established by evaluation of 100 berry mass, yield per bush and the ratio of high productivity to low productivity seedlings was determined from the mean of the experiment mean. The results from this study indicated that fertilization had a positive influence on the yield in all trials where the yield increased in a mean of three years. In the first experimental year the influence of fertilization on the yield components was moderate compared with the second and the third years when the yield increased by 41% and 48%, respectively. Berry mass and yield per bush were more influenced in the second and third experimental years. In the first year when fertilizers were applied to the soil there was observed no significant influence of fertilization. In the Estonian conditions, for lowbush blueberry growing on commercially managed fields, it is important to choose the source of plant material. As the variability of seedlings is high it is recommended to use vegetatively propagated plant material. The yield of seedlings fluctuated from 168 to 2126 g per bush and the mean of the experiment was 468 g per bush.

Keywords: berry mass, yield, fertilization, opencast peat pits.

T. Suuroja, E. Lepp, T. Järveots.  
  About thyroid gland normality of calves 304
About thyroid gland normality of calves. The thyroid gland of 37 calves 0–30 day old of two breeds’ Estonian Red and Estonian Holstein were investigated. Thyroid gland mass, volume, density dimensions of lobules and follicles, and the height of follicular epithelium were measured. The relationship between thyroid gland mass and histological structure was investigated. Relationship between thyroid gland morphology and other organs (lungs, liver, kidneys, brain, intestine, thymus) pathomorphology was investigated.

The material for light microscopy was fixed in buffered neutral formaldehyde solution (10%). Speciemens were stained with haematoxylin-eosin and van Gieson.

The results of the study showed that there is no obvious relationship between the histological structure and mass of the thyroid gland. The mean mass of the thyroid gland was 13,6 g and the volume 14,4 cm3. Patho-morphological changes was found in 19 thyroid gland of calves. There were found pathomorphological changes in other organs that are lungs, liver, kidneys and intestine.

Keywords: thyroid gland, morphology, pathomorphology, age, weight, calf.

A. Viltrop, J. Alaots, S. Põldma, J. Parik, M. Pärn, K. Must.  
  Genetic typing of some BVDV strains from Estonia and molecular epidemiology of the infection 311
Genetic typing of some BVDV strains from Estonia and molecular epidemiology of the infection. The report describes the results of the genetic typing of the Estonian BVDV strains on the bases of polymorphism of the 5’ untranslated region (UTR) of the virus genome. 11 virus strains originating from four administrative districts of Estonia were genetically typed. The phylogenetic analysis of Estonian strains together with foreign strains was performed and the genotype of Estonian BVDV strains was established.

All the Estonian BVDV isolates investigated in the present study appear to belong to the BVDV genotype 1and are closely related to Western-European strains: 9 of the strains could be classified as BVDV genotype 1b (the sequence homology with strain Osloss >93%). Two Estonian strains were distinct from the rest of Estonian strains having sequence homology less than 90% with other strains. These two strains could be classified as BVDV genotype 1f when compaired to strains of different BVDV genotypes.

The Estonian BVDV strains are highly herd-specific. Only in two herds identical virus strains were discovered. In one herd the introduction of a new virus strain could be identified as the isolates dating back to 1995 were clearly distinct from isolates of 1999 and 2000.

Keywords: Bovine viral diarrhoea virus, BVDV, genotypes, 5’ untranslated region, molecular epidemiology.

  This year's fourth issue of the Journal of Agricultural Science article on page 226 had a technical fault. Figure 3 correct subscript is:

Joonis 3. Uriini hapete ja aluste ekskretsioon erineva jõusöödasisaldusega ratsioonide tarbimisel
Figure 3. Excretin of urine acid and base when intaking the ration with a different content of concentrates


  This year's fifth issue of the Journal of Agricultural Science have misleading error. M. Järvan et. al article "Effect of liquid nitrogen fertilizer and rare earths on spring wheat" completed the target-financed research topic number 0110193s98 context.