2000 * XI * 4

CONTENTS
 
CONTENTS
DIRECT LINK
https://agrt.emu.ee/pdf/contents/2000_4_sisukord.pdf
 
 
K. Annuk.  
  On plant growing experiments in Estonia and Northern Livonia in the 19th century and the first two decades of the 20th century. 4. 256
 
ABSTRACT
On plant growing experiments in Estonia and Northern Livonia in the 19th century and the first two decades of the 20th century.

Most of the cultures grown in Estonia were used in the experiments. Moreover, the experiments were performed to find some new cultures besides potato, clover and lucerne. Fr. v. Berg, a landlord from Sangaste, achieved a great success in this field. K. Sponholz, N. v. Dehn and A. Eisenschmidt were known as the fosterers of experimentation at the experimental establishments. Regarding peasantry, Joh. Zirk and the owners of the Tõlla farmstead, father and son Hans Meltsas, carried out successful experiments. Jul. Aamisepp has expressed the following opinion on the experimental activities of that period (1885…1914) – “It was the period of conductingoriented experiments.”

DIRECT LINK
https://agrt.emu.ee/pdf/2000_4_annuk.pdf
 
J. Kuum.  
  130 years (1870…2000) of horticultural and agricultural societies in Tartu 275
 
ABSTRACT
130 years (1870…2000) of horticultural and agricultural societies in Tartu. The article gives a brief survey of the activities of horticultural and agricultural societies in Tartu within 130 years. During this time these societies have had different names but one aim: to give their members theoretical and practical knowledge of horticulture and agriculture in the form of lectures, courses, exhibitions and through professional literature.
DIRECT LINK
https://agrt.emu.ee/pdf/2000_4_kuum.pdf
 
TEADUSTÖÖD
A. Kaasik, E. Pedak, H. Kask.  
  Influence of heat treatment on the degradability of crushed oats dry matter and some amino acids in the rumen of dairy cattle 280
 
ABSTRACT
Influence of heat treatment on the degradability of crushed oats dry matter and some amino acids in the rumen of dairy cattle. A trial was carried out to investigate the effect of short heat treatment (120 °C for 15 min) on the degradability of dry matter, lysine and arginine of crushed oats. Trial was carried out according to the Swedish in sacco method.

Heat treatment of crushed oats decreased (P>0.05) effective degradability of dry matter from 67% to 66.5%. Effective degradability of lysine of treated oats was slow and reduced. In untreated samples 84.5% of lysine was degraded while thermal treatment reduced degrad-ability by 1.5% to 83%, respectively (P<0,01). Also, thermal treatment affected and reduced degradability of arginine in crushed oats. Arginine degradability of untreated crushed oats was 83.7% while thermal treatment reduced degradability by 1.8% to 81.9%, respectively (P<0,01).

On the basis of the results of the trials the following conclusions can be drawn:

  1. Heat treatment slightly reduced decomposition of hardly soluble and degradable fraction of dry matter consisting mainly structural carbohydrates i.e. cellulose. This is not desirable for rumen fermentation while total digestibility of cell-wall compo-nents will be reduced.
  2. The effect of heat treatment on lysine degradation was higher at the initial phase of rumen fermentation. During the first two hours of incubation the degradation of lysine in untreated crushed oats was by 7% higher – 86% compared to 79%, respec-tively. Reduced effective degradability of lysine and slow decomposition process in treated oats is caused most likely by formulation of isopeptides, lysine-alanine complex and increased concentration of L-isomer. However, those components are practically undigestible in the small intestine.
  3. The largest difference (3.2%) of arginine degradation between the test variants was after incubating the samples in rumen for four hours – 85.9% and 82.7%, respec-tively.
  4. The results of the trials indicated that the amount of compound feed given with the diet have a significant effect on the effective degradability of crushed oats dry matter and most likely on the dry matter of all other cereals as well. Increased amount of compound feedstuff reduces degradability of its dry matter.
DIRECT LINK
https://agrt.emu.ee/pdf/2000_4_kaasik.pdf
 
R. Kask, U. Jõgi.  
  On the soil structure of Estonian arable lands 291
 
ABSTRACT
On the soil structure of Estonian arable lands. Like on non-arable lands, the structural characteristics of arable soils (on different fields or different parts of the same field) are connected with soil typical units. Sod-calcareous and gleyed soddy soils, which are, on the average, richer in humus and have a better reaction, have – as a rule – better structural characteristics than sod-podzolic soils.

The structural differences of arable soils are the most closely related to soil texture. In the texture sequence from light over middle to heavy soils we can observe an increase of aggregation as well as of the stability of the aggregates to wards the effect of water, wind and mechanical pressure. Light-textured soils are aggregated slightly, which makes them easy to cultivate (lumpiness presents no problem), but they are also easily eroded by wind. Light soils together with peaty gley and peaty soils make up nearly a third of all arable soils in Estonia. In middle-textured soils the aggregate reading is relatively good. In harvest-time the macroaggregated part of the soil is, in most cases, over 80%, in the ploughed layer the part of water-stable aggregates is over 50% in the >25 mm fraction, while the dispersion factor of the microaggregate fraction (<0.01 mm) stays within 0.4–0.5. In middle-textured soils the lumpiness is moderate. If such fields are cultivated in an optimum time and way, lumpiness should present no problem. Heavy-textured soils are distinguished as strongly lumpy. This is particularly characteristic of soils with a low humus content, the eroded soils found in southern Estonia and the soddy gley soils of western Estonia. The formation of lumps during cultivation renders the cultivation process considerably more difficult in about 10% of the Estonian arable lands.

Aggregation, as well as other characteristics of soil structure, changes in time. During the 1990s the use of fertilisers (organical included) considerably decreased in Estonia. This implies that the aggregation of the Estonian soils has dropped during the past decade. An additional factor responsible for the weakening of aggregation is the deepening of the ploughed layer into the lower (illuvial or eluvial) horizons.

DIRECT LINK
https://agrt.emu.ee/pdf/2000_4_kask.pdf
 
H. Kiiman, O. Saveli.  
  Working procedures in machine milking and its connection with milk somatic cell count 306
 
ABSTRACT
Working procedures in machine milking and its connection with milk somatic cell count. A milking machine facilitates milking, but at the same time a milker has to take a great responsibility. To avoid udder damages, the utilisation instructions of a milking machine should be followed.

Data were collected from six dairy farms. In three farms Rezekne pipeline milking equipment and in two farms Alfa Laval pipeline milking equipment were used. In one farm there was milked with Rezekne as well as Alfa Laval pipeline milking equipment. Monitoring of the working operations of the 23 milkers was carried out. The duration of each element of the working process was recorded.

SAS program was used for data processing. Procedure REML was used to estimate dispersion components.

From these data analysis it was concluded that the adequate pre-milking cow preparation for milking was essential considering milk yield as well as milk somatic cell count (P<0.05). Late lactation cows required more stimulation to achieve good milk let down compared with early lactation cows.

Application of the milking unit to the cow is the other essential operation. Milking unit should be applied to the cow as soon as cow preparation is completed. There were seven milkers did not be late in attaching the milking unit to the cow. Maximum delay in the appli-cation of the milking unit to the cow was 5 hours and 18 seconds. From these analysis observed, that the delay in application of the milking unit to the cow essentially affected the milk somatic cell count (P<0.05).

In the case of overmilking higher milk somatic cell count (P<0.001) and lower milk yield per cow (P<0.05) were observed.

DIRECT LINK
https://agrt.emu.ee/pdf/2000_4_kiiman.pdf
 
A. Kiis, M. Reinik, K. Ilmoja, K. Kaart.  
  Determination of sulphur dioxide and sulphites in food 311
 
ABSTRACT
Determination of sulphur dioxide and sulphites in food. Sulphur dioxide and sulphites are widely used as food preservatives. They inhibit growth of moulds, yeasts and aerobic bacteria. It has been shown in toxicological experiments that these sulphur compounds may cause headache, inhibit growth, decompose vitamins thiamine and biotine and also lead to deficiency of tocoferol in organisms.

In 1998 and 1999 a monitoring project for determination of sulfites’ concentrations in food was carried out in Estonia. Laboratory analyses were passed at the Tartu Department of Central Laboratory of the Estonian Health Protection Inspectorate.

In 1999 200 food samples both of domestic and imported origin were analysed.

Sulphur dioxide was removed from samples by microdestillation, analyses were carried out spectrophotometrically. Limit of determination was 5 mg/kg, measurement uncertainty 5%. Method of analysis T27-KOL used at the Tartu Department of Central Laboratory is accredited by the Estonian Board of Standards.

47 samples (24%), most of them wines and dried fruit, contained residues of sulphites. In three samples – red wine Latest Harvest Chardonnay, apricots in Amaretto sauce and marinated champignons – the violations of maximum permissible limit concentrations were found. Contents of sulphites were close to limit concentrations in some wine samples and in dried apricots.

DIRECT LINK
https://agrt.emu.ee/pdf/2000_4_kiis.pdf
 
V. Meriloo, K. Laas.  
  Experimental estimation of engine power of agricultural machine 318
 
ABSTRACT
Experimental estimation of engine power of agricultural machine. Relationship between power of diesel engine and engine speed has a linear character if we take into account automatically regulated branch of curve. With help of appliance ИМД-ЦМ (indicator of engine power) it is possible to indicate the power of diesel engine in relationship of temperature of engine. So it is possible to find driving power of potato digger by engine speed with help formula (6). We see that the formula (6) gives a relationship between Nm and some independent variables. To compute a quantity of Nm as a function of these independent variables and taking into account absolute limits on the individual errors the absolute error of ΔNm is given by formula (7). Example of calculations by formula (7) in the case of using one-row rotation potato digger is given in tab. 1. Maximum computed absolute error of needed power of potato digger ΔNm is ±0,40 kW or 8% as seen in table 1. Calculations with help formula (6) are given in table 2.
DIRECT LINK
https://agrt.emu.ee/pdf/2000_4_meriloo.pdf
 
R. Piir.  
  The saskatoon as fruit crop 322
 
ABSTRACT
The saskatoon as fruit crop. In the article, only 8 species of the Amelanchier genus are discussed. None of them are native in Estonia, but they have been introduced here. There are more or less information about their accommodation in the climate of this country. Originating in North America, the saskatoons are grown in Europe and Asia as ornamental and hedge plants: due to abundant flowering and autumn colour of foliage. Fruits are edible but not much used for fruit crop in Estonia. People who are interested in fruit production must learn the experience of North America (both Canada and the prairie regions of the USA) where the saskatoon has long been a treasured fruit, being a staple fruit for prairie people for centuries, especially due to very good winter hardiness of the plants and tolerating wide ranges of soil. In Estonia, A. spicata and A. alnifolia are the most potential two species for fruit production by the beginners. Saskatoon cultivars have been selected, up to the present, from the wild, mostly in Canada. However, less suckers per plant, best bush form and lower height, uniformity of ripening, fruit size, lessening the quantity of seeds and size of the core are the objects of breeding in the future. Fruits are a good quality raw material for juice, jam and wine production, as well as eating out of hand.
DIRECT LINK
https://agrt.emu.ee/pdf/2000_4_piir.pdf