Refine search
Results 411-420 of 2,106
Analysis of climatic factors in connection with strawberry generative bud development Full text
2014
Kalnina, I., Latvia Univ. of Agriculture, Jelgava (Latvia);Latvia State Inst. of Fruit-Growing, Dobele (Latvia) | Strautina, S., Latvia State Inst. of Fruit-Growing, Dobele (Latvia)
Strawberries (Fragaria× Ananassa Duch.) are widely grown in Latvia, and it is the first berry crop that ripens in summer. In Latvia, climate conditions are very suitable for strawberry growing. Unfortunately, meteorological conditions have become very changeable in recent years. The short day (SD) strawberry cultivars are the most important ones for Latvia, as they initiate flower buds in autumn. For these cultivars it is important to initiate flower buds at the end of September till the end of October. The day length has to decrease less than 14 hours per day to begin this process. In Latvia, the day length below 14 hours per day is at the end of August. The second important limiting factor for initiation of flower buds is the average day temperature, which must be between 10 and 15 °C. The studies on strawberry flower bud initiation in Latvia were done long time ago, on a very small scale and fragmentary. The current paper analyzes the temperature regime during the period of previous ten years (2004 – 2013) in autumn in Dobele in relation to suitability of this climatic factor to the flower bud initiation and strawberry yield next year. The soil surface temperatures during the last ten years in August were about +20 °C, which means that the flower bud initiation could not occur as early as it was described in the previous study.
Show more [+] Less [-]Lodging cause height at the centre of gravity changes during vegetation period for oat Full text
2014
Brunava, L., Latvia Univ. of Agriculture, Jelgava (Latvia);State Stende Cereals Breeding Inst., „Dižzemes”, Dižstende, Lībagi parish, Talsi municipality (Latvia) | Alsina, I., Latvia Univ. of Agriculture, Jelgava (Latvia)
Height at the centre of gravity is a part of mathematical model to interpret risk of lodging used for cereal crops. Because of the anatomical changes during vegetation period, several measured parameters in early milk stage (stem and panicle weight) will differ from over-ripe stage results in their values. The aim of this study was to define approximate values of calculated parameters describing oat (Avena sativa L.) height at the centre of gravity in early milk and over-ripe stages as well as determine connection with lodging risk. The trial was carried out at the State Stende Cereals Breeding Institute in 2013. There were 5 oat cultivars studied. At the investigated growing stages plant samples were taken from a field and in laboratory conditions stem/panicle weight and length measured. The height at the centre of gravity and gravity ratio were calculated using mathematical model by Berry (1998). Results showed that the value of the height at the centre of gravity in over-ripe stage was significantly higher (p is less than 0.01) than in early milk stage, but correlation with risk of lodging remained. Such lodging resistance describing mathematical model can be useful for oat as well as wheat cultivars.
Show more [+] Less [-]Fertilisation effect on biomass formation of perennial grass used as energy crop Full text
2014
Rancane, S., Latvia Univ. of Agriculture, Jelgava (Latvia) | Karklins, A., Latvia Univ. of Agriculture, Jelgava (Latvia) | Lazdina, D., Latvian State Forest Research Inst. Silava, Salaspils (Latvia)
Bioenergy production growth rates in the recent years are leading to waste – digestate and wood ash amount increases, which are essential to be managed in the most efficient and safe way. In the formation of plant nutrient recycling these waste products are useful to be included in the energy crop fertilisation plan. In order to study the waste products application options for energy crops – reed canary grass (Phalaris arundinacea L.) and festulolium (×Festulolium pabulare) fertilisation trials were arranged in 2012 at the Skriveri Latvian University of Agriculture (LLU) Research Institute of Agriculture. In all fertiliser treatments: wood ash; digestate one time per season; digestate two times per season and mineral fertilisers the same doses of the main plant nutrients (N, P, K) were provided, the missing quantities of elements compensating with mineral fertilisers. To obtain the grass biomass, two cutting regimes were used – two-cut and one-cut harvest system. This article summarizes the findings on the productivity of the 1st year of use grassland swards and sward structure data. The productivity of perennial grass biomass was dependent on the type of applied fertilisers, grass species and cutting regime. In the first production year the highest average dry matter yield (7.30 t haE-1) was produced by reed canary grass. The highest DM yields in average for both grass species were obtained by mowing once per season – in autumn at crop senescence (7.01 t haE-1) and in fertilisation treatments of wood ash (WA) – 8.06 t haE-1 and mineral fertilisers (MF) – 7.24 t haE-1.
Show more [+] Less [-]The quality of Latvian warmblood broodmares and their progeny depending on type and origin Full text
2014
Orbidane, L., Latvia Univ. of Agriculture, Jelgava (Latvia) | Jonkus, D., Latvia Univ. of Agriculture, Jelgava (Latvia)
In breeding of Latvian Warmblood breed carriage type horses Equus caballus one of major breeding objectives is producing of typical purebred animals with minimal influence of modern warmblood breeds. The aim of the study was to analyze the quality of Latvian Warmblood horse breed carriage and sport type mares included in the register of Latvian Horse Breeding Association broodmares and differences between types in valuation and quality of progeny. The data included 135 records from Latvian Warmblood horse breed mares having valuation both of conformation and performance. The data from 79 sport type and 56 carriage type broodmares were collected. The majority of mares in population (31.9%) had proportion 0 – 24.9% of Latvian warmblood purebred ancestors. The proportion of Latvian Warmblood purebred ancestors in the group of carriage type mares was high – 72.2%, while sport type mares – only 23.4%, a difference between groups was significant (p is less than 0.01). Sport type mares showed significantly (p is less than 0.05) better results in conformation and performance quality whereas carriage type broodmares had significantly higher count of daughters registered in Stud book. Comparison of breed types showed that groups did not differ significantly by height of withers and quality of progeny. Lower quality of conformation and performance of carriage type had to be explained by pedigree data as the main criteria for acceptance, also with older age of broodmares. For future the main goal has to be censorious licensing of best carriage type stallions and using young broodmares with higher quality of gaits and conformation for breeding purpose.
Show more [+] Less [-]Dairy cow behaviour at individual feeding bins, can we estimate intakes from behavioural observations? Full text
2014
Soonberg, M., Estonian Univ. of Life Sciences, Tartu (Estonia) | Arney, D.R., Estonian Univ. of Life Sciences, Tartu (Estonia)
Estimating feed intakes of individual cows in a loose-housed system is difficult and unreliable. It is known that estimating intakes from the number of bites taken at grazing is unreliable. Feeding from a total mixed ration (TMR) is likely to have fewer confounding variables. All cows were over 30 months old, of three breeds: Holstein Friesian, Estonian Red and Estonian Native. There were 30 feeding bins and 66 cows. Cows were observed over the whole 24 hour period, from 1st July to October 22nd 2011, in Märja experimental farm, of the Estonian University of Life Sciences, and data from 37 cows were collected. Measures taken included: time spent at the feed bin, number of bites taken at each visit, weight lost from the bin, and evidence of stealing. Mean time spent at each visit to the feed bin with standard error was 4.4 + 0.68 minutes. The mean number of bites per visit was 7.1 + 1.01. There was a significant correlation between the number of bites and total time cows spent feeding (p is less than 0.001), with a regression R2 value of 79.8%. No correlation was found between the number of bites and feed removed at each visit (p=0.851) nor between the time per visit and amount of feed removed (p=0.681). Therefore, there is no evidence that either the number of bites taken per visit or the time spent at bin per visit is related to intakes. There was no effect of age. Stealing was evident and widespread.
Show more [+] Less [-]Attitudes of Latvian adults to the consumption of pulses Full text
2014
Kirse, A., Latvia Univ. of Agriculture, Jelgava (Latvia) | Karklina, D., Latvia Univ. of Agriculture, Jelgava (Latvia)
Pulses (Fabaceae) are an excellent source of nutrients with protein content equal to the protein of meats. Regularly choosing such meat alternatives as pulses can help minimize the amount of saturated fat and increase the amount of fibre in the diet. New pulse products could benefit vegetarians and people struggling with new diet changes. The aim of this study was to determine pulse consumption patterns of Latvian adults. An 11 question survey was developed on an online survey website www.visidati.lv to analyse consumer attitudes towards pulse consumption in Latvia. The questionnaire was completed by 780 respondents from September to December 2013. During the Baltics food industry fair ‘Riga Food 2013’ five question survey was carried out after vegetarian bean spread tasting. The questions were related to pulse consumption and preference; five questions survey consisted of overall preference and quality determination of the product. The results show that the majority of Latvian omnivore adults consume pulses about once a week or less; while pulse intake in vegetarian adults is significantly higher (p is less than 0.05). Latvian adults prefer green peas (Pisum sativum L.), navy and broad beans (Phaseolus vulgaris L.), lentils (Lens culinaris Medik.), chickpeas (Cicer arietinum L.) and maple peas (Pisum sativum L. var. arvense). Overall preference of vegetarian bean spread with sun-dried tomatoes (Solanum lycopersicum L.) is ‘like very much’ (4.5 – 4.6) and most of the respondents would purchase this product if it was available in a store.
Show more [+] Less [-]Microbiological composition assessment of bread kvass Full text
2014
Lidums, I., Latvia Univ. of Agriculture, Jelgava (Latvia) | Karklina, D., Latvia Univ. of Agriculture, Jelgava (Latvia)
Kvass is a non-alcoholic beverage produced by fermenting kvass mash with yeast; alcohol content in kvass must be less than 1.2% alcohol by volume. Microbiological safety of kvass is an important issue because European Regulation No 2073/2005 on microbiological criteria for foodstuffs does not provide microbiological criteria for kvass production. Microbiological safety of kvass depends on raw materials, personal hygiene, environment, kvass blending and filtration. Experiments were carried out at the Latvia University of Agriculture Department of Food Technology from November 2013 to January 2014. The aim of this work was to assess the microbiological environment changes during kvass production process and shelf-life. Understanding the development of dynamic of microbiological environment provides a better management for kvass production processes. Samples of bread kvass were analysed during production (12 and 13 h) and storage (36, 60, 84, 132, 136 h) at 3 ± 1 °C to determine kvass quality. Yeasts (LVS EN ISO 21527 - 2: 2008), lactic acid bacteria (ISO 9332:2003) and total plate count (LVS EN ISO 4833:2003) were determined in kvass samples. Microorganisms in kvass were identified using API identification system; the dominating microflora in kvass was Saccharomyces cerevisiae and Leuconostoc mesentericus. Changes of total plate count during fermentation and maturation were not significant (p is greater than 0.05).
Show more [+] Less [-]Purification of egg yolk oil obtained by solvent extraction from liquid egg yolk Full text
2014
Kovalcuks, A., Latvia Univ. of Agriculture, Jelgava (Latvia)
There are different methods of egg yolk oil extraction, but still solvent extraction is commonly used. Due to the high cost of egg yolk powder production, extraction of lipids from liquid egg yolk remains very topical. Crude egg yolk oil obtained by solvent extraction from liquid egg yolk contains high amount of water which can decrease shelf life of egg oil promoting lipid oxidation. High concentration of residual solvents limits the usage of egg oil in food or in cosmetics due to the health risks. The aim of this study is to purify egg yolk oil obtained by solvent extraction from liquid egg yolk. Results show that it is possible to decrease the water content in egg oil from 14.26 ± 1.29% to 0.88 ± 0.13% by eliminating lecithin from egg oil. Solvent evaporation in the rotary film evaporator under the vacuum cannot remove solvents completely from the extract, but nitrogen streaming through the extract as a last step in evaporation process removes solvent residues, leaving behind high quality egg yolk oil suitable for food application.
Show more [+] Less [-]Jerusalem artichoke flour feeding effects on calf development in the first months of life Full text
2014
Arne, A., Latvia Univ. of Agriculture, Jelgava (Latvia) | Ilgaza, A., Latvia Univ. of Agriculture, Jelgava (Latvia)
Studies have been conducted to find out the effect of the feeding of calves (Bos Taurus) with Jerusalem artichoke (Helianthus tuberosus) concentrate produced in Latvia containing the prebiotic – inulin. The study was performed on two groups of animals - a control group of 8 animals and test (prebiotic) group of 8 animals in summer (from June to August, 2013), and winter (from December, 2013 to February, 2014) in one of cow farm of Latvia, in the municipality of Bauska. Both groups were fed the whole milk, but the test group received additionally 12 g of Jerusalem artichoke powder (an average of 500 g kgE-1 inulin) per day. The overall health status and physiological parameters (temperature, heartbeat and breathing frequency) of both animal groups before the study were of the normal range. After the experiment, we found out that the calves of the test group during both winter (one case) and summer seasons (seven cases), had fewer cases of diarrhea than the control (winter months four cases and summer months nine cases) group animals, the average daily weight gain (control group 0.53 g, prebiotic group 0.75 g) and the total weight gain (control group 29.42 kg, prebiotic group 42.13 kg) during 56 test days was significantly higher ( p is less than 0.05) than that for the control animals. We concluded that the use of Jerusalem artichoke flour concentrate when fed to the calves generally gives positive impact on the development and growth of the calves, improves the status of the gastrointestinal tract and the morphometric indicators.
Show more [+] Less [-]Alaria spp. epizootiological situation in wild boar in Latvia Full text
2014
Berge, V., Latvia Univ. of Agriculture, Jelgava (Latvia) | Keidane, D., Latvia Univ. of Agriculture, Jelgava (Latvia)
During the controls for Trichinella in wild boar meat, Alaria spp. mesocercariae in the examined samples are diagnosed. There does not exist a routine veterinary inspection for diagnosis of alariosis (Alaria spp.) in Latvia. The aim of the study was to determine Alaria spp. mesocercariae distribution in wild boar (Sus scrofa) meat in Latvia. Laboratory examination was performed in Latvia University of Agriculture Faculty of Veterinary Medicine laboratory of Parasitology, from 2010 to 2013. Meat samples were examined using artificial digestion method, which in regulation No 2075/2005 is considered an official detection method for Trichinella. In total, 1233 wild boar meat samples from different hunting regions of Latvia were examined. The territory of Latvia was divided into four regions – Kurzeme, Zemgale, Vidzeme and Latgale. For examination we used meat samples from wild boar pillars of diaphragm. Samples were taken from wild boars of different age and gender. The prevalence of infection in the examined wild boar meat samples from all regions was 8.2%, but the intensity of infection 2.8.
Show more [+] Less [-]