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Comparison of different solvents for isolation of phenolic compounds from horseradish (Armoracia rusticana L.) leaves Texto completo
2013
Tomsone, L., Latvia Univ. of Agriculture, Jelgava (Latvia) | Kruma, Z., Latvia Univ. of Agriculture, Jelgava (Latvia)
Horseradish (Armoracia rusticana L.) is a perennial herb belonging to the Brassicaceae family and contains biologically active substances. The aim of the current research was to determine the most suitable extraction method and solvent for obtaining horseradish leaf extracts with high antiradical activity. For experiments fresh leaves of horseradish were extracted with seven different solvents: n-hexane, diethyl ether, 2-propanol, acetone, ethanol (95%), ethanolwater/acetic acid (80/20/1 v/v/v) and ethanol / water (80/20 by volume) using two extraction methods (conventional and Soxhlet). For all extracts, total phenolic, flavonoid content and DPPH˙, ABTS radical scavenging activity, and reducing power were determined using a spectrophotometric method. As the best solvent can be used ethanol. Total phenolic content and total flavonoid content was higher in Soxhlet extracts. Comparing to other plants, the proportion of flavonoids in the amount of total phenolics is average, and it increases by increasing the polarity of used solvent. It can be concluded that by using Soxhlet extraction method it is possible to obtain extracts that are effective antioxidants. A very strong and a strong correlation has been identified between levels of phenolic compounds and antioxidant capacities of the extracts.
Mostrar más [+] Menos [-]Evaluation of butter oil oxidative stability and nutritional value affected by cow feeding Texto completo
2013
Antone, U., Latvia Univ. of Agriculture, Jelgava (Latvia) | Sterna, V., Latvia Univ. of Agriculture, Jelgava (Latvia) | Zagorska, J., Latvia Univ. of Agriculture, Jelgava (Latvia)
Nutritional value and shelf life of milk and dairy products depend on the composition and stability of their constituents. The aim of the present study was to evaluate the effects of carrots as cow feed carotenoid source on butter oil fatty acid (FA) composition and oxidative stability. Milk was obtained from one trial group (TG; n=5) and one control cow group (CG; n=5) in a conventional dairy farm in Latvia. TG cows received carrots 7 kg per cow per day; the length of the supplementation period was 39 days. The stability of butter oil exposed to sunlight (3h) and held for 14 days in the temperature of 60 °C was analyzed by peroxide value method. The changes of the FA content and ratios in TG milk fat were more positive with respect to the fat nutritional value as observed in CG – stronger increase in the content of polyunsaturated FA (p is less than 0.05), and in the ratio between stearic and palmitic acids (p is less than 0.05); also a tendency was seen of increasing content of short and monounsaturated FA, as well as decreasing the ratio between ω6 and ω3 FA groups. Oxidative stability of the carrot supplemented cow group’s milk butter oil samples that were collected after 25- day trial period, exposed to sunlight (3h) and stored at a temperature of 60 °C was significantly (p is less than 0.05) higher compared to CG samples. After the 39-day long trial period stability difference was not significant, despite the tendency that average polyunsaturated FA content in TG samples was higher compared to the control.
Mostrar más [+] Menos [-]Interaction of selenium and vitamin E in eggs and egg yolk oil Texto completo
2013
Kovalcuks, A., Latvia Univ. of Agriculture, Jelgava (Latvia) | Duma, M., Latvia Univ. of Agriculture, Jelgava (Latvia)
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.
Mostrar más [+] Menos [-]Serological aspects of avian metapneumovirus infection in Kazakhstan Texto completo
2013
Mussoyev, A., Kazakh National Agrarian Univ., Almaty (Kazakhstan) | Assanov, N., Kazakh National Agrarian Univ., Almaty (Kazakhstan) | Mussina, G., UNIVET LLP (Kazakhstan) | Sansyzbai, A., Kazakh National Agrarian Univ., Almaty (Kazakhstan) | Valdovska, A., Latvia Univ. of Agriculture, Jelgava (Latvia)
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%.
Mostrar más [+] Menos [-]Immunocorrecting therapy of allergic dermatitis Texto completo
2013
Omarbekova, G., Kazakh National Agrarian Univ., Almaty (Kazakhstan) | Muralinov, K., Kazakh National Agrarian Univ., Almaty (Kazakhstan) | Kozinda, O., Latvia Univ. of Agriculture, Jelgava (Latvia) | Makhmutov, A., Kazakh National Agrarian Univ., Almaty (Kazakhstan) | Muralinova, J., Kazakh National Agrarian Univ., Almaty (Kazakhstan
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.
Mostrar más [+] Menos [-]Correlation between productivity of cows sired by different breeding bulls and blood biochemical parameters of their blood Texto completo
2013
Dujina, I., Latvia Univ. of Agriculture, Jelgava (Latvia) | Jemeljanovs, A., Latvia Univ. of Agriculture, Jelgava (Latvia)
The objective of the study was to examine how the circumstances of different bull daughters – Latvian Brown cow - group productivity levels correlate with the blood biochemical composition indices in Latvian conditions. The daughters of seven bulls, selected for our research trial, were kept in the same barn and under rearing conditions. Their blood samples were taken in a single sampling activity and analyzed for blood serum biochemical averages. Also Cu, Fe, Zn, Mn and Mg were detected in blood serum and the values found were compared with values fixed in regulatory documents. There were changes in Cu levels (daughter groups of four bulls), in Zn levels (one group); Mn level was lower in all groups and Mg level was higher in 6 groups. The altered biochemical parameters of blood were assessed from the pathogenetical point of view and compared with productivity averages in the progeny groups. The correlation factors suggested that there exist a strong positive correlation (p is less than 0.05) among a number of indicators, such as aspartate aminotransferase (ASAT) and protein r = 0.823; ASAT and somatic cell count (SCC), r = 0.737; blood protein and milk protein r = 0.903 - 0.917; albumins and protein r = 0.964; blood urea and milk protein r = 0.931 - 0.984 along with additional correlations. The correlation factors for the progeny group of each bull differed. The data obtained shows that the Latvian Brown cows crossed with other breeds produce cows with new genetic traits.
Mostrar más [+] Menos [-]Veterinary sanitary characters of cattle meat infected by leptospirosis Texto completo
2013
Kuzembekova, G., Kazakh National Agrarian Univ., Almaty (Kazakhstan) | Kirkimbayeva, Z., Kazakh National Agrarian Univ., Almaty (Kazakhstan) | Sarsembaeva, N., Kazakh National Agrarian Univ., Almaty (Kazakhstan) | Paritova, A., Kazakh National Agrarian Univ., Almaty (Kazakhstan)
This article presents data on veterinary and sanitary evaluation of cows’ (Bovis) meat infected by leptospirosis. The material for the study was a sample of muscle tissue of m. longissimus dorsi taken at slaughter of 10 cows (Bovis) kept on farms in Almaty region. The following parameters have been examined in muscle tissue: water, protein, fat, ash, amino acid composition. Besides the biochemical studies we also measured pH of meat, put the reaction of neutral formalin (Formalin test) and determined the biological value of meat. It was determined that physical and chemical characteristics of sick animal meat have significant deviations from the norm. Such meat rapidly accumulates products of protein decay. The amount of essential and nonessential amino acids decreases, which indicates low nutritional value of meat. Meat of cattle infected by leptospirosis concedes by nutritional and biological value comparing to meat of healthy animals.
Mostrar más [+] Menos [-]Calcium and phosphorus content in Roman snail (Helix pomatia) meat and shell Texto completo
2013
Ikauniece, D., Latvia Univ. of Agriculture, Jelgava (Latvia) | Jemeljanovs, A., Latvia Univ. of Agriculture, Jelgava (Latvia)
The aim of the study was to determine and compare calcium and phosphorus content in pedal mass, visceral mass and shell of wild and bred trial groups’ snails (Helix pomatia). The trial was performed from May to September of 2011 at the Roman Snail Research Facility of the Research Institute of Biotechnology and Veterinary Medicine „Sigra”, of Latvia University of Agriculture (LLU). Snails were divided in 4 trial groups depending on the diets. Samples were collected from the local natural population of snails and experimental breeding farm in spring (May), summer (July) and autumn (September). Significant differences (p is less than 0.05) were found between the levels of the calcium and phosphorus content in the edible part (pedal mass) and visceral mass in wild snails and experimental trial groups.
Mostrar más [+] Menos [-]Morphometric and masometric parameters of the ostrich (Struthio camelus) stomach in postnatal ontogenesis Texto completo
2013
Mancevica, L., Latvia Univ. of Agriculture, Jelgava (Latvia) | Mugurevics, A., Latvia Univ. of Agriculture, Jelgava (Latvia)
Stomach, as a part of the digestive canal, is important in the metabolic processes of the organism which affects the bird’s general health condition, its growth and development, consequently also the increase of the body weight. The aim of the research was to find out the dynamics of weight, length, and area of the ostrich (Struthio camelus) stomach and its parts in postnatal ontogenesis from 4 to 12 months of age. The absolute weight of stomach, length of the greater curvature of the stomach glandular part, diameter of the muscular part, thickness of stomach wall was determined. To find out the differences of the mean values between various age groups, ANOVA and Post Hoch tests were used. The increase of the stomach absolute weight continued throughout the postnatal ontogenesis period, but the stomach weight in relation to the ostrich body weight decreased, especially rapidly at the age of 6 and 8 months. At the same time, proportions of the absolute and relative weight of the stomach glandular and muscular part changed. The length of the greater curvature of the stomach glandular part, length of the deep gland region and diameter of the stomach muscular part increased during the whole observed period of ontogenesis; moreover, these parameters increased more rapidly from 6 to 8 months of age. The area of the stomach glandular and muscular part mucosa increased throughout the observed period of ontogenesis. The area of the superficial gland region in all age groups was larger than the area of the deep gland region.
Mostrar más [+] Menos [-]Solar air heating collector energetic efficiency Texto completo
2013
Ruskis, G., Latvia Univ. of Agriculture, Jelgava (Latvia) | Aboltins, A., Latvia Univ. of Agriculture, Jelgava (Latvia) | Palabinskis, J., Latvia Univ. of Agriculture, Jelgava (Latvia)
The aim of investigations was to compare different absorber material efficiency to examine collector tracking the Sun and stationary collector efficiency as well as the efficiency of insulated and non-insulated collectors. The 0.1x0.5x1.0 meter long experimental solar collectors were constructed for investigations and different types of absorber materials were made. The manifold length, the Sun radiation effect on the degree of air heating was analyzed. ASHARE used standard 93-2003 is determined for insulated and non-insulated solar collectors and absorber effectiveness. We determined the influence of the Sun radiation on the air heating degree for those types of absorbers. The experimental data were measured and recorded in the electronic equipment REG (electronic metering and recording equipment of temperature, radiation and lighting). The collector covered material was a polystyrol plate and different absorbers. We compared insulated and non-insulated collectors to prove that the insulated collector is more effective. The insulated collector was made of the collector surfaces faced with cellular plastic two cm plates. Our task was to calculate the air heating solar collector efficiency. The collector tracking the Sun is approximately 30% more efficient than the same type of stationary collectors in operation time for 6 hours. Insulation increases solar panel efficiency especially in windy weather. The insulated collector demonstrates almost two times higher efficiency than the non-insulated collectors (up to 93%) with absorbent material steel tinplate on top.
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