Several fungicide applications are used to control a pear scab (Venturia pirina Aderh.) on pear (Pyrus communis L.) trees. Minimal chemicals use in fruit-growing constantly has been important condition in the integrated fruit production; therefore, sanitation is recommended to reduce a primary inoculum in orchards. The study was carried out in an integrated pear orchard located in Sigulda district, in the central part of Latvia to estimate if a fall treatment of a pear orchard with urea reduces an amount of pseudothecia and pear scab incidence level the following season. Six treatments trial was arranged in the autumn 2011 on a moderately susceptible pear cultivar ‘Belorusskaya Pozdnaya’. An amount of leaf litter, pseudothecia and incidence level of a disease on leaves and fruits were determined. The results showed that urea application reduced both an amount of leaf litter and a number of pseudothecia. An average amount of leaf litter was 127 leaves per 0.25 square m in a control and 89 leaves in a treatment with urea application. The number of pseudothecia reached 250 pseudothecia per one leaf disc in a control and 160 pseudothecia in a treatment with the urea application, the difference was not significant (p is greater than 0.05). The reduction of disease incidence level on leaves was significant (p is less than 0.05) only in the first assessment of five in total.

Oat breeders have improved yielding ability potential of oat (Avena sativa L.) cultivars, but set lower standards for biochemical composition of grain. Nowadays the quality of grain for consumers has become important especially in terms of lipids and β-glucan content. Experiments were carried out at State Stende Cereal Breading Institute in the year 2012 to evaluate the oats yield and grain quality. 15 different cultivars of Stende collection were compared by yield and parameters of productivity (test weight and 1000 kernel weight) as well as biochemical parameters (protein, starch, lipid, β-glucan, content). Biochemical parameters were tested by Infratec Analyser 1241. To obtain an equal research background all cultivars were grown in a plant breeding crop rotation field, with similar growing conditions (sowing-time, fertilizer, plant protection activities), which agree with generally accepted technology of oat cultivation in Latvia. Experiments were done in four replications. Plots were laid randomized. ANOVA procedures were used for data analysis. Yield of experimental cultivars varied between 4.28 ± 0.19 - 5.93 ± 0.22 t haE-1, test weight 46.85 ± 0.99 - 52.75 ± 0.44 kg hLE-1, 1000 kernel weight 33.70 ± 0.24 - 46.34 ± 0.80 g. Significant differences of tested yield parameters among oat cultivars were observed. The highest protein content was observed for local breed cultivars ‘Arta’ and ‘Mara’ 119.5 ± 02.6 and 110.5 ± 1.9 g kgE-1 accordingly. Low starch content, but high β-glucan content is characteristic for all Latvian cultivars.

Agricultural farms in modern production system are specialized; therefore, animal-origin organic fertilizers are not available for many of them. Researches on the use of organic products in agriculture to restrict the use of pesticides and mineral fertilizers have been performed for a long time. Nowadays different organic preparations that are acquired as a result of complex processes are produced, ensuring ready-to-use biologically active substances in them and also activating their properties. One of the purposes of the research was to evaluate the impact of extracts from organic products on the potato (Solanum tuberosum) yield and tuber quality in the conventional cultivation system. A field experiment using cultivars ‘Borodyansky Rozovij’ (early maturity) and ‘Lenora’ (mid-early maturity) was arranged in the State Stende Cereals Breeding Institute in 2011 and 2012. Peat elixir and vermicompost extract obtained at different temperatures: + 45 °C and + 95 °C, as well as a mixture of these extracts were used for treatment of tubers and plants. The research included 24 treatments in total, including control (without treatment) and a standard potato cultivation technology. Tubers were treated immediately before planting, but plants were treated three times during the vegetation period. Average two-year research results showed that the use of organic product extracts significantly (p is less than 0.05) affected the tuber yield in different treatments for both cultivars ‘Borodyansky Rozovij’ and ‘Lenora’. The content of nitrates in tubers, using extracts, did not exceed the allowable level (160 mg kgE-1) in any of treatments.

In the last years total area of buckwheat (Fagopyrum esculentum) has increased notably in Latvia, including the Eastern part of the country but there is a lack of actual information about buckwheat growing, best terms of sowing and seeding rates. This study presents the influence of different sowing times, methods and rates on the seed quality of buckwheat yield – (TGW) thousand grain (nutlet) weight and (HLV) bulk density. A field experiment was conducted on the farm “Arāji”, Krāslava region in 2010 and 2012. Buckwheat was sown on six different dates - 15.05, 25.05, 30.05, 05.06, 10.06 and 15. 06. Two types of sowing were used – drill sowing, where 4 seed rates were used - 200, 300, 400, 500 fertile nutlets per m2 , and the column sowing with the three seed rates - 150, 250, 300 fertile nutlets per square m. It was found out that crop sowing time and type significantly affected buckwheat yield quality. Compensation mechanisms of yield in early terms of sowing when lower seeding rates were used were expressed less than that in later sowing terms. It could be concluded, that in early terms different seeding rates could be used with equal success. In later terms of sowing, smaller seeding rates are more appropriate. After two year investigation the most suitable sowing terms were around 4th and 9th June, where TGW and HLW was the highest. The most inappropriate terms were around 25th and 30th May, because meteorological conditions after sowing in both years were unfavorable that resulted in 0.5 to 1.0 t haE-1 lower yields.

TThe aim of this study was to evaluate an impact of nitrogen fertilizer rates on industrial hemp’s (Cannabis sativa L.) growth and development in Latvia. The trial was carried out during 2012 on the Research and Study farm Peterlauki of the Latvia University of Agriculture in the sod calcareous soil. There were three industrial hemp cultivars ‘Futura 75’, ‘Tygra’ and ‘Felina 32’ tested under different fertilizer rates: N0P0K0 – control, N0P80K112 – background fertilizer (in text marked as F), F+N30, F+N60, F+N90, F+N120, F+N150, F+N180 kg haE-1. Weather conditions were proper for good hemp biomass production. Depending on the selected cultivars, the optimal fertilizer rate was in the range of 90 – 150 kg ha-1. Industrial hemp stalk length was significantly (p is less than 0.05) influenced by the applied nitrogen fertilizer rate and cultivars. The highest stalk length was observed in the cultivar ‘Futura 75’ under all nitrogen fertilizer rates. The highest stalk length (3.18 m) had reached under the nitrogen fertilizer rate 150 kg haE-1 at 138 growing day from sowing. At the beginning of growing season (June - July) the growth intensity of hemp stalk length is high. Within one month the stalk length grew up for 1.23 meters of cultivar ‘Futura 75’. The intensive growth of hemp stalk declines when the flowering stage is reached. Flowering stage occurred in early August, and it was dependent on nitrogen fertilizer rate. Under higher nitrogen fertilizer rate the flowering stage reached later.

The traditional consumption of citrus juices as a breakfast beverage has historical ties to obtaining one’s daily requirement of vitamin C. Vitamin C is one of the most important vitamins found in citrus juices, including orange juice. The aim of the study was to determine the effect of processing and storage on the content of vitamin C in orange juice varieties of ‘Valencia’ and ‘Navel’ of orange juice. The content of vitamin C (mg 100 gE-1) was determined with the iodine method in freshly squeezed orange juices and in pasteurized and packaged in aseptic bags orange juices of ‘Valencia ‘and ‘Navel’ variety, after processing and during 24 weeks of storage at 20 ± 1 °C and 5 ± 1 °C. The study results showed that the average content of vitamin C in freshly squeezed orange juice ‘Valencia’ was found at 33.56 mg 100gE-1 but in freshly squeezed orange juice ‘Navel’ the content of vitamin C was higher than in ‘Valencia’ variety orange juice average at 46.18 mg 100gE-1. The loss of vitamin C for both orange juices on average about 7% during processing The storage study showed that after 24 weeks of storage at 5 ± 1 °C and at 20 ± 1 °C, in pasteurized orange juice ‘Valencia’ the content of vitamin C decreased by 9.83% and 19.73 respectively. In the pasteurized orange juice ‘Navel’ the content of vitamin C decreased by 8.53% and 15.24% respectively.

In modern life oxidative stress has a serious effect on human health; therefore, natural antioxidants play an important role in human well-being. Hen (Gallus gallus domesticus) eggs can be effectively enriched with selenium and vitamin E and can be used as a source of natural antioxidants. The objective of this study was to determine the interaction of selenium and vitamin E in eggs and egg yolk oil. Two groups of Lohman Brown-Classic breed laying hens from a real production facility were taken as an experimental object. The basal diet was the same for both groups and content 25 mg kgE-1 of vitamin E added. 0.2 mg kgE-1 of sodium selenite was used as an inorganic source of selenium in feed for one hen group and 0.3 mg kgE-1 of organic selenium in the selenized yeast form for the other group. The selenium content was determined in eggs, egg yolk, egg white and egg yolk oil samples and vitamin E content in egg yolks and egg yolk oil. The results of this study indicate that there is no difference in selenium content in eggs from inorganic and organic selenium hen diet taking into account that selenium content in feed was different. The majority of selenium is located in egg yolk, but there was no selenium detected in egg yolk oil. Vitamin E content in egg yolks was not affected by the source of selenium (p is less than 0.05). High vitamin E content in egg yolk oil effectively protects egg yolk oil from oxidation during storage.

The objective of this study was to observe and evaluate the ability of innovative vascular prosthesis, made in Riga Technical University (RTU), to incorporate in a canine model. The research has been performed in Veterinary Medicine Faculty of Latvia University of Agriculture since July 19. 2011. The research was approved by the Food and Veterinary Service of the Republic of Latvia. The research is realized within the framework of European Social Fund co-financed project ‘Establishment of interdisciplinary research groups for new functional properties of smart textiles development and integrating in innovative products’ (ESF No 2009/0198/1DP/1.1.1.2.0./09/APIA/VIAA/148). RTU produced aortic grafts 5-8 mm in diameter and 8 mm to 18 mm long were implanted retroperitoneal in 9 female, 1-3 years old Beagle dogs. Once before and regularly after the surgery, abdominal aortic and vascular graft diameter was measured in cross sections. Blood pressure was measured before and regularly after the procedure. Results show no significant differences in aortic and graft diameter before and 12 months after the operation and there are no significant differences in systolic and diastolic blood pressure before and 6 months after the aortic surgery at a significance level α 0.05. The study shows that the innovative aortic prostheses do not change in diameter and abdominal aorta transplantation surgery does not cause significant variations in blood pressure. Study is continued to find out later reactions to synthetic vascular graft.

Avian metapneumovirus (AMPV), formerly known as avian pneumovirus (APV) is epizootic agent of turkey rhinotracheitis (TRT) and swollen head syndrome (SHS) in turkeys and chickens. The infection primarily affects the upper respiratory tract of young birds (broilers), while also decreases egg production of adult hens. Thus, the development of infection in susceptible birds of any age can cause serious economic losses. The purpose of this study is to test serums from broilers and hens for the presence of antibodies against the avian metapneumovirus. In this series of studies 317 serum samples taken from one 1 day to 75 weeks old birds were tested. Thus, on the basis of serological tests of blood serum and of chicken flocks and broilers, we had a preliminary diagnosis on the presence of avian metapneumovirus infection. Serological studies of unvaccinated against avian metapneumovirus infection bird flocks using the ELISA method showed antibody titers on average at 22 859 ± 4133. Avian metapneumovirus infection in birds was accompanied by a decrease in egg production of chicken flocks by 8.0 - 12.8%.

This article summarizes data of determining a therapeutic dose of a new immunocorrecting drug, dermatocytoglobulin, developed by the authors of this study. It has been established that this drug has a therapeutic immunocorrecting effect on allergic dermatitis. Subjects of the study cattle, horses, of Raimbek – Commercial Diary Farm, 56 dogs and 35 cats admitted to a veterinary clinic. It has been established that administration of dermatocytoglobulin in trial groups reduces autoantibody titers until their elimination on the 12th day, dose of 0.2 cm3 per 10 kg while autoantibody titers in control groups were identified on the 30th day.