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Cell proliferation activity in lymph nodes infected by Porcine circovirus-2 Полный текст
2017
Piginka-Vjaceslavova, I., Institute of Food Safety, Animal Health and Environment BIOR, Riga (Latvia) | Birgele, E., Latvia Univ. of Agriculture, Jelgava (Latvia)
High economic losses in agriculture can be caused by pig disease like Postweaning Multisystemic Wasting Syndrome (PMWS). Porcine circovirus-2 (PCV2) is the primary agent of PMWS. It is known that PMWS causes cellular and humoral immunity disorders, therefore it is considered a general immune deficiency disease in piglets. It is still unknown, why piglets with PMWS have severe loss of lymphocytes in lymphoid tissues and in the blood. Thus, the hypothesis of the study was that lymphocyte depletion occurs because of lymphocyte life-cycle delay in pigs infected by PCV2. The activity of cell life-cycle is attributed to protein Ki67. This protein is found in all active phases of the cell like interphase G1, S, G2 and mitoses. However, protein Ki67 is not observed at all in the cell’s “quiet” phase G0. The aim of our work was to investigate the lymph node cell proliferation activity of pigs infected by PCV2. In total, 42 pig carcasses were collected from 5 to 15 weeks old pigs with PMWS clinical manifestation. Lymph nodes were selected from each pig carcass for histological and immunohistochemical testing. We concluded that B lymphocyte population was reduced first in the lymph node with PCV2, but the number of T lymphocytes decreased later. PCV2 decreased B lymphocyte proliferation activity.
Показать больше [+] Меньше [-]Antimicrobial resistance of Aeromonas spp. isolated from the sea trout (Salmo trutta L.) in Latvia Полный текст
2017
Revina, O., Institute of Food Safety, Animal Health and Environment BIOR, Riga (Latvia);Latvia Univ. of Agriculture, Jelgava (Latvia) | Avsejenko, J., Institute of Food Safety, Animal Health and Environment BIOR, Riga (Latvia) | Cirule, D., Institute of Food Safety, Animal Health and Environment BIOR, Riga (Latvia) | Valdovska, A., Latvia Univ. of Agriculture, Jelgava (Latvia)
The aim of this study was to investigate the patterns of antibiotic resistance of Aeromonas spp. bacteria isolated from the sea trout (Salmo trutta) from the state fish hatcheries of the Institute of Food Safety, Animal Health and Environment ‘BIOR’, Latvia. Bacteriological investigations were performed at four state fish hatcheries located in the drainage basins of the main Latvian rivers – Daugava, Venta and Gauja, during the five-year period (2012 – 2016). In fish with visible clinical signs, bacteriological samples were collected from heart, liver, spleen, kidney and ulcer surfaces. Aeromonas hydrophila and Aeromonas salmonicida were isolated from sea trouts. A total of 52 individual sea trouts were examined. Resistance to amoxicillin, ampicillin, cephalexin, colistin, doxycycline, enrofloxacin, erythromycin, florfenicol, gentamycin, kanamycin, lincomycin, neomycin, oxytetracycline, spectinomycin, streptomycin, tetracycline, trimethoprim/sulfamethoxazole was tested. The results of this study suggest a multi-drug resistance pattern among the A. hydrophila isolates. All the isolates were resistant to amoxicillin (100%), ampicillin (100%), cephalexin (100%) and erythromycin (100%). The lowest level of resistance was found against florfenicol (4.55%), gentamycin (4.55%), kanamycin (4.55%), but susceptibility was recorded to enrofloxacin, neomycin and trimethoprim/sulfamethoxazole. A. salmonicida isolates were resistant to oxytetracycline (9.38%) and tetracycline (9.38%). For other antibiotics A. salmonicida isolates were susceptible.
Показать больше [+] Меньше [-]Estimation of yield and yield stability of spring barley genotype mixtures Полный текст
2017
Locmele, I., Latvia Univ. of Agriculture, Jelgava (Latvia) | Legzdina, L., Latvia Univ. of Agriculture, Jelgava (Latvia) | Gaile, Z., Latvia Univ. of Agriculture, Jelgava (Latvia) | Kronberga, A., Latvia Univ. of Agriculture, Jelgava (Latvia)
Organic farmers need varieties adapted to variable growing conditions, because in organic farms environmental conditions significantly vary in soil nutrient status, weed and disease pressure not only between years, but also among farms within a season. Modern varieties developed under high input agricultural systems do not always perform well under organic growing conditions. Therefore, farmers need such varieties of cereals that can adapt to variable growing conditions and maintain productivity. One of the ways to promote adaptation to environment is growing of variety mixtures. Field trials were conducted during 2014 – 2016 under organic and conventional farming systems in two locations with an aim to estimate the advantages of barley mixtures in respect of yield and its stability. The trial consisted of eight mixtures of barley varieties and breeding lines, components of mixtures in pure stand and three check varieties. The mixtures were combined by using two, three and five components. Three mixtures, each in one out of 11 environments significantly out–yielded, but one mixture had significantly lower yield than the average value of their components. Some mixtures showed a tendency to out–yield the average of components in both farming systems. All mixtures insignificantly out–yielded check varieties in 2015, but in 2016, yield was within the range between varieties with lowest and highest yield. The results of yield stability analysis showed that mixtures could be used as one of the approaches to stabilize yield – only one of eight mixtures had a lower yield than the average over all environments.
Показать больше [+] Меньше [-]Insight in edamame yield and quality parameters: a review Полный текст
2017
Zeipina, S., Latvia Univ. of Agriculture, Jelgava (Latvia) | Alsina, I., Latvia Univ. of Agriculture, Jelgava (Latvia) | Lepse, L., Latvia Univ. of Agriculture, Jelgava (Latvia)
Environmental conditions and climate change on a global scale affect the overall agriculture and food supply. Edamame, also called vegetable soybean is an import vegetable in the world, especially in the East Asia. China is the world’s centre for vegetable soybean production. Edamame beans are harvested before full maturity when bean pods are green and just before turning to yellow colour. Most cultivated varieties in the world are of Japanese origin. The aim of this literature survey is to give a review on history and consumption facts of edamame, as well as on the yield and quality parameters of this fresh commodity. Monographic method has been used for this review. Edamame has a high nutritional and medical value. Composition of biologically active compounds in edamame plants is dependent on climate conditions, seasonal changes, cultivar properties and maturity stage. Vegetable soybean has a long cultivation history in the world. In Europe edamame is grown, but in Latvia edamame has not been grown until now, but there is some experience in soya grain growing. Pod colour is the main external quality factor of edamame. It can be influenced by light, moisture, fertilization, variety properties, planting density and harvesting procedures. Vegetation period for edamame in most cases is reported to be between 75 and 100 days. Environmental conditions and climate change on a global scale affect the overall agriculture and food supply. Edamame, also called vegetable soybean is an import vegetable in the world, especially in the East Asia. China is the world’s centre for vegetable soybean production. Edamame beans are harvested before full maturity when bean pods are green and just before turning to yellow colour. Most cultivated varieties in the world are of Japanese origin. The aim of this literature survey is to give a review on history and consumption facts of edamame, as well as on the yield and quality parameters of this fresh commodity. Monographic method has been used for this review. Edamame has a high nutritional and medical value. Composition of biologically active compounds in edamame plants is dependent on climate conditions, seasonal changes, cultivar properties and maturity stage. Vegetable soybean has a long cultivation history in the world. In Europe edamame is grown, but in Latvia edamame has not been grown until now, but there is some experience in soya grain growing. Pod colour is the main external quality factor of edamame. It can be influenced by light, moisture, fertilization, variety properties, planting density and harvesting procedures. Vegetation period for edamame in most cases is reported to be between 75 and 100 days.
Показать больше [+] Меньше [-]Slaughter results analysis of grass-fed beef cattle Полный текст
2017
Muizniece, I., Latvia Univ. of Agriculture, Jelgava (Latvia) | Kairisa, D., Latvia Univ. of Agriculture, Jelgava (Latvia)
Cattle fattening, first of all, should be beneficial for a farmer, therefore, in Latvia more suitable are such average intense fattening methods as fattening with grass fodder. In the world, demand for beef, produced in an environmentally friendly manner, ensuring the appropriate animal welfare conditions, is growing. The aim of the study was to find out the fattening results of Hereford (HE) and Aberdinanguss (AB) pure-bred bulls and their crosses when fed with grass fodder. The study was conducted in 2015 and 2016 within the framework of the project ‘Baltic Grassland Beef’. AB crossbreed bulls were slaughtered when they were 519 ± 16.6 days old, but HE pure-bred bulls − 584 ± 7.3 days old (p ≤ 0.05). The biggest live weight and slaughter weight showed HE crossbreed group bulls – 557 ± 19.4 kg and 293 ± 12.2 kg, respectively, but the biggest live weight daily gain from birth to slaughter was observed to AB pure–bred group bulls – 952 ± 24.7. Carcass conformation score in muscle development was the highest for AB pure–bred group bulls. Their average conformation score was 3.2 ± 0.08 points. In terms of fat score development, carcass with the best quality was obtained from HE crossbreed group bulls, the resulting fat score – 2.4 ± 0.10. The obtained results prove that pure-bred and crossbreed bulls used in this research are suitable for fattening with grass in the conditions of Latvia
Показать больше [+] Меньше [-]Number of services per conception and its relationship with dairy cow productive and reproductive traits Полный текст
2017
Cielava, L., Latvia Univ. of Agriculture, Jelgava (Latvia) | Jonkus, D., Latvia Univ. of Agriculture, Jelgava (Latvia) | Paura, L., Latvia Univ. of Agriculture, Jelgava (Latvia)
The aim of our study was to determine up to what extent the number of services per calving (NSPC) affects dairy cow productive and reproductive performance. The study contains data from the Agricultural Data Centre of Latvia about 26888 Latvian Brown (LB) and Holstein Black and White (HBW) breed cows that were born from year 2005 – 2010, closed at least 5 full lactations and were culled from herds. In data set we have included data about cow milk productivity (calculated in ECM), longevity traits and reproduction traits. The reproduction traits included the number of services per conception (NSPC), calving interval (CI) and calving to conception interval (CCI) in the first five lactations. The average lifespan of LB and HBW dairy cows was 3149.5 days and in this period 39570.6 kg ECM were obtained. LB breed cows were characterized by 23.5 days longer lifespan and by 6035.4 kg ECM lower lifetime milk productivity than HBW breed cows, but they showed higher reproduction trait scores than LB breed group. HBW cows had a significantly (p is less than 0.05) higher NSPC, CCI, number of milking days (MD) and CI than LB breed cows in all five analysed lactations. The NSPC in the first lactation increased the calving age at the fifth lactation – cows with NSPC in the first lactation is greater than 4, fifth time calved 170.7 days in LB breed group and 190.8 days in HBW breed group later than cows with one NSPC in the first lactation.
Показать больше [+] Меньше [-]The influence of kappa-casein and beta-lactoglobulin genotypes on milk coagulation properties in Latvia dairy breed Полный текст
2017
Petrovska, S., Latvia Univ. of Agriculture, Jelgava (Latvia) | Jonkus, D., Latvia Univ. of Agriculture, Jelgava (Latvia) | Zagorska, J., Latvia Univ. of Agriculture, Jelgava (Latvia) | Ciprovica, I., Latvia Univ. of Agriculture, Jelgava (Latvia)
Milk yield, composition and milk coagulation properties can be affected by kappa-casein (κ-CN) and beta-lactoglobulin (β-LG) genotypes and breed. Latvian Brown (LB) and Latvian Blue (LZ) are local dairy breeds in Latvia. These breeds are not so high-yielding than other commercial dairy breeds, besides, the number of those animals decrease each year. The aim of the research was to analyse the influence of κ-CN, β-LG and breed on milk composition and milk coagulation properties. Data were collected from 56 Latvian Brown and 26 Latvian Blue in 2016. Widespread κ-CN genotype was AA (0.593) in LB breed and AB (0.636) in LZ breed, while β-LG highest frequency was BB genotype. Significant effect was not observed on milk yield; however the highest daily milk yield was from AB κ-CN genotype (19.7 ± 1.52 kg) in LB breed. Significant differences were observed in fat content – the highest fat content accordingly κ-CN was from AA genotype in LB (46.3 ± 1.89 g kgE-1) and 45.5 ± 1.37 g kgE-1 from BB β-LG genotype in LB breed (p is less than 0.05). A lower protein content was observed from AA κ-CN genotype in LZ breed (33.8 ± 1.30 g kgE-1), while highest from BB genotype in both breeds. Curd firmness was not significantly different by genotypes and breed. Significantly shorter milk renneting time of β-LG was obtained from LB breed (14.6 ± 2.76 min, p is less than 0.05), while κ-CN genotype was not significantly affected.
Показать больше [+] Меньше [-]Concentrate distribution to sheep using automatic feeding station Полный текст
2017
Senfelde, L., Latvia Univ. of Agriculture, Jelgava (Latvia) | Kairisa, D., Latvia Univ. of Agriculture, Jelgava (Latvia)
The research was conducted with the aim of studying the possibility of using automatic feeding stations for individual sheep (Ovis aries) feeding. The research was organized in 3 periods, in which 10–13 months old sheep – female only (1st research period), 6–10 months old sheep – female only (2nd research period) and 8–12 months old sheep – female only (3rd research period) were used. Part of the sheep did not visit the feeding station at all. Sequentially, over the research periods the percentage was 13%, 37% and 49%. Upon setting the concentrate daily ration 400 g per sheep, on the average the number of visits to the particular feeding station was 6.1 and 4.7 (sequentially in the 1st and 2nd research period). Upon increasing the concentrate ration amount up to 700 g per day, the average number of feeding station visits was 6.9 (in the 3rd research period). The number of visits to the automatic feeding station was varied (V is greater than 10%). Over the research period live weight of the sheep increased significantly (p ≤ 0.05) for the subgroups of animals which made visits to the feeding station regularly during the entire research period. In all research periods, the average daily concentrate intake (373.5 g in the 1st research period, 333.1 g in the 2nd research period and 581.2 g in the 3rd research period) was 93%, 83% and 83% respectively, of the maximum established feeding standard.
Показать больше [+] Меньше [-]Development trends in the national economy sectors in the Baltic States in 2005-2015 Полный текст
2017
Supe, L., Riga Technical Univ. (Latvia) | Jurgelane, I., Riga Technical Univ. (Latvia)
The processes of globalization in the world economy have a significant impact on different processes and development in all national economy sectors. Innovations and technological development have also increased the competition between economic operators. Faster growth is also observed in service industries. The global economic downturn affected the Baltic States whose development suffered a sharp decline at the end of 2008 and in 2009. A sudden drop in the demand in export markets, as well as the decline in the demand in the domestic markets due to low purchasing power contributed to the deterioration of the economic situation in the Baltic States, particularly in the manufacturing and construction sectors. Starting from 2011, the economic indicators in the Baltic States have been growing and here the export of goods and services can be mentioned as the main contributor to the development of the economy in the Baltic States. Significant changes in the development of economic sectors started in 2013 due to Russia’s economic problems. During the period 2005 – 2015, most of the value added to the overall structure of the national economy in all three Baltic States was brought by trade and manufacturing. The aim of the research is to analyse the national economy sectors in the Baltic States during the period 2005 – 2015 in order to determine processes that affected the development of economy sectors in each of the countries, or the opposite – the recession, thus finding the most competitive sector of the national economy of the Baltic States.
Показать больше [+] Меньше [-]Support payments for agriculture and rural development in Latvia Полный текст
2017
Pilvere, I., University of Latvia, Riga (Latvia) | Nipers, A., University of Latvia, Riga (Latvia) | Pilvere-Javorska, A., Baltic Advisory, SIA, Dobele (Latvia)
The European Union (EU) Common Agricultural Policy (CAP) affects the development of the agricultural industry and rural areas in all the Member States. A very important role is played by various support payments as one of the policy instruments. The CAP has been developing and is being reformed; therefore, it is important to assess the effect of various CAP support instruments on the development of the agricultural industry. Therefore, the research aim is to assess the support instruments and kinds of support as well as their effects on selected agricultural indicators. The research study proceeds in three stages or phases: first, the identification of the total amount of support payments paid and the key kinds of support; second, a detailed analysis of the key kinds of support; third, the identification of associations between the amounts of support payments and other agricultural and farm performance indicators. The research found that in the period 2005 – 2014 in Latvia, the total amount of support amounted to EUR 4.3 billion, of which EUR 520 million or 12% were received by approximately 1000 FADN farms. The most significant kinds of financial support in Latvia were direct payments, accounting for 47% of the total amount of support and financial assistance provided for rural development with 39%. The total amount of financial support and the amount of area-based payments affected the key agricultural indicators as well.
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