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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Reprodukcinių savybių ir jas įtakojančių veiksnių analizė Lietuvoje veisiamų juodmargių galvijų populiacijoje / Analysis of reproductive features and factors influencing these features in the black & white cattle population in Lithuania

Petraškienė, Rasa 22 November 2005 (has links)
The aim of the present study. To make analysis of reproductive features and factors influencing these features in the black & white cattle population in Lithuania. Novelty of the study: First is made the exhausting analysis of reproductive features in the black & white cattle population in Lithuania; first are investigated factors influencing reproductive features in the black & white cattle population in Lithuania. Estimated relations of correlation between reproductive features and productivity. Practical significance of the study. Influence of genetic and non-genetic factors on reproductive features in the black & white cattle population in Lithuania, correlation of reproductive features, and relations of reproductive features and productivity are investigated. In concordance with these results, in development breeding programs of the dairy cattle, it is necessary to add selection of reproductive features. Are corrected ranges of reproductive features which can be used when will be prepares data for an estimation of breeding values of the reproductive features of the black & white cattle population.
2

Lietuvos pieninių galvijų pieno baltymų genetiniai tipai ir jų ryšys su produktyvumu / Genetic types of milk proteins prevalence and their relation with production traits in Lithuanian dairy cattle breeds

Peciulaitienė, Nijolė 23 September 2005 (has links)
First time was investigated distribution of genes coding for milk protein diversity in Lithuanian dairy cattle population and milk protein genes influencing milk yield and composition. According to research results, offer take into account to specific genes loci in cattle genome, influencing expression of desirable milk protein types. Select animals, owning Kapa-casein B and Beta-lactoglobulin B alleles and create specific cattle herds be able to produce qualitative milk suitable for curd and cheese industry. Obtained results could be maintained as official selection criterion, genetically improving milk renneting traits in Lithuanian dairy cattle population.
3

Chlorelės poveikis paršavedžių produktyvumui ir paršelių augimo spartai / Chlorella impact on productivity of sows and speed of piglet‘s growth

Šidagis, Darius 21 March 2006 (has links)
Purpose of the study: to assess chlorella impact on productivity of sows and on speed of piglets’ growth. This research of master degree was accomplished in 2004-2006 in Animal Nutrition Department of Lithuanian Veterinary Academy, in feed research laboratories of Agrochemical Investigations Centre of Lithuanian Institute of Agriculture and joint stock company AB “Kauno Grūdai“ and in breeding-ground of farmer G. Charitonovas (Žadeikonių village, Pasvalio region) with the swine of the Swedish Yorkshire breed of the first group. Research revealed that: 1. during suckling period mass reduction in sows, that were given a suspension of chorella during pregnancy period, was lower by 14.5% compared to the control group containing sows that were fed by combined feeds only (p<0.05); 2. prolificacy of the test group sows was by 10.0% higher (p>0.05), piglets produced by them were 9.6% heavier (p<0.05) and families of born piglets where less varied when compared to the control group; 3. sows of the test group that were given a suspension of chorella were by 10.98 kg or 22.4% milkier when compared to the sows of control group (p<0.05); 4. chorella had a positive impact on change of piglets mass: piglets at birth were by 9.6%, on the 21st day of life – by 8.4%, on the 35th day of life, i.e. at the wean off – by 7.6% heavier when compared to the piglets of control group (p<0.05); 5. in the test group retention of piglets was as follows: on the 10th day of life – by 2.2%, on the 21st day... [to full text]
4

Biotechnologinių priemonių panaudojimo galimybės deoksinivalenolio detoksikacijai kviečiuose / The possibilities of biotechnological devices in usage of deoksinyvalenole in detoxication of wheat

Laivienė, Vilma 19 April 2007 (has links)
The aim of this work was to investigate DON in wheat with Acoustic and ELISA methods, and look if in biotechnological processes such as the sourdough bread making process and the bio-ethanol fermentation process have influence on the amount of DON in dough and bread and on the DON content in DDGS (Distillers Dried Grains with Solubles) as residue of the bio-ethanol process which is used for feed purposes. A collection of wheat has been taken from the Lithuanian Agriculture Institute at Dotnuva and the DON content has been determined by Acoustic and ELISA methods. Both methods are in reasonable correlation with each other (R2 = 0,735) and applied on the raw material wheat. The aim of the second part of the study was to apply different sourdough bacteria (L. bulgaricus and L. acidophilus) in the bread making process and to determine the DON content in dough and bread with the ELISA method. The reduction of DON was noticed in both Lactobacillus applications but was the best by applying L. bulgaricus. The pH had no influence on the detoxification process in the dough. In the third part of the study the bio-alcohol fermentation process showed that with an optimal mixture of amylase- glucoamylase respectively an enzyme preparation (Vilzim SKK 350 AV) a good reduction of DON in DDGS could be obtained. (44, 5%) With these results it is recommended as to use sourdough processes in the manufacture of bread in Lithuania which is already common practice to reduce DON in bread and... [to full text]
5

Paršavedžių išbrokavimo dėl skirtingų priežasčių ekonominis įvertinimas / Analysis of reasons for removal of sows and economic evaluation

Juraitis, Arvydas 19 April 2007 (has links)
Objective – To evaluate the correlation of sows removing genotype and farm conditions on the reproduction indicators. Research goals: 1. To analyse genotype and farm conditions influence to researching reproductions indicators of the sows; 2. To evaluate the influence of sows removing genotype and farm conditions on the reproduction indicators; 3. To evaluate removals reasons correlation with sows reproductions indicators. Research methods: The aim of the study was to evaluate how parameters of lifetime productivity differ for females having distinct removal reasons and was to describe the reasons for removal of sows distributed across parity categories data analysis was done with Microsoft Excel 2000 program. We have calculated research attribute medium values and bias (SE). Using general linear model we have investigated (genotype, farm and condeming reasons) fact influens for research reproduction index. Reproduction problems and diseases represented two third of all removals. Too early sows removing is one of the determinative factor which decreasing pigs drove reproduction and farm profitability.
6

Mineralinių medžiagų panaudojimas dėsliųjų vištų ir viščiukų broilerių mityboje / Use of minerals in laying hens and broiler chickens nutrition

Kaminskienė, Jurga 17 March 2008 (has links)
Per pastaruosius 20 metų daug pasiekta auginant viščiukus broilerius – ženkliai padidėjo viščiukų augimo greitis ir maisto pasisavinimo efektyvumas. Šiuolaikiniai komerciniai hibridai greitai vystosi ir jiems reikia daug energijos turinčių lesalų, kurie leidžia maksimaliai išnaudoti jų genetines galimybes. Daugiau pasiekta ir vištų dedeklių lesinime balansuojant lesalus skirtingais dėslumo etapais, ypač ankstyvojo dėjimo periodu. Pastaruoju metu paukščių lesinime didelis dėmesys skiriamas optimaliam kalcio, fosforo, natrio, kalio ir chloro subalansavimui. Parinkus netinkamas kalcį ir fosforą nešančias medžiagas, taip pat nesubalansavus natrio, kalio ir chloro tarpusavio santykio, t.y. anijonų katijonų balanso, padidėja vandens suvartojimas, sutrinka virškinimo trakto mikrobiologinė pusiausvyra, blogėja kraiko kokybė ir mikroklimato parametrai, susidaro sąlygos paukščiams susirgti ascitais, padaugėja paukščių staigių gaišimo atvejų. Vitaminai ir mineralai yra svarbi sudedamoji paukščių raciono dalis. Šios medžiagos įtraukiamos į racioną kaip priedai atitinkamais kiekiais, kad būtų patenkintas jų poreikis sveikiems produkciją duodantiems paukščiams. Mineralų ir vitaminų trūkumas gali būti kritiškas tam tikrais organizmo vystymosi etapais, todėl kai kurie autoriai teigia, kad net ir trumpas vitaminų bei mineralų apribojimas augimo fazės metu gali turėti neigiamų pasekmių. Magistrinio darbo tikslas – nustatyti mineralinių medžiagų įtaką dėsliųjų vištų ir viščiukų broilerių... [toliau žr. visą tekstą] / Minerals play a very important role in digestion and metabolism of poultry. They are necessary, for the maintenance, growth, production and health of birds. Laying hens also require minerals, primarily calcium, for eggshell formation. Minerals is divided into the macrominerals (those needed in relatively large amounts) and the micro- or trace minerals. Although microminerals are required only in small amounts, the lack of an adequate dietary supply can be just as detrimental to poultry as a lack of one of the macrominerals. Grains are low in minerals, so all poultry feeds contain supplemental sources. Calcium, phosphorus and salt are needed in the greatest amounts. Microminerals such as iron, copper, zinc, manganese and iodine are normally supplied through a trace mineral mix. The minerals influence by the bird‘s physiological status, requirement of minerals and its source is describe in the theory part. Two experiment were performed with broiler chickens and laying hens. The feed intake, feed conversion ratio, birds mortality, the degree of mineralization in the bone tibia, pH, macroelements Ca, P, Mg, Na, K, Cl and alkaline phosphatase in the blood serm were researched in experiment of broiler chickens. Number and weight of eggs, body weight, laying intensity, leftover and utilization of feed to get 1 kg eggs mass, quality parameters of eggshells, the physiological conditions and mortality reasons were researched in test of laying hens. Conclusions. Sodium bicarbonate was... [to full text]
7

Maisto grandinės valstybinės kontrolės efektyvumo analizė / Food chain state inspection efficiency analysis

Narijauskienė, Inesa 18 March 2008 (has links)
Baigiamojo darbo tikslas buvo išanalizuoti Vilkaviškio rajono maisto tvarkymo subjektų (toliau – Įmonės) valstybinės kontrolės efektyvumą ir nustatyti jų tikrinimo dažnumą atsižvelgiant į rizikos laipsnį, maisto saugos ir kokybės sąvokas bei jas kuriančių veiksnių visumą. Supažindinti su Lietuvos Respublikos valstybinės maisto ir veterinarijos veikla, užtikrinant maisto saugą ir kokybę teisiniais reglamentais, maisto produktų saugos valdymo ir maisto technologijos ypatumais. Šiame darbe siekiama parodyti, koks svarbus maisto kontrolėje yra saugios darbo vietos sukūrimas, maisto kokybės kontrolės vykdymas, produkcijos kokybės vertinimas. Baigiamajame darbe išsamiai analizuojami maisto saugos ir kokybės ypatumai bei privalumai. Nagrinėjami maisto kokyb�����s ir saugos terminai, maisto higienos reikalavimai, bendrieji kontrolės principai, standartinės veiklos programos. / The aim of the work was to analyze the efficiency of public control of the food management subjects of Vilkaviškis region (thereinafter Company) and to set the periodicity of their control considering the risk level, the concept of food safety and quality as well as the set of factors which create it. Also, to introduce the peculiarities of food safety management and food technologies. The work is intended to demonstrate the importance of safe work place establishment, food quality control performance and production quality evaluation. Food safety and quality peculiarities as well as advantages are thoroughly analyzed in the work. Possibility to improve and assure the safety of produced food taking into consideration consumers’ health is also analyzed. The terms of food quality and safety, food hygiene requirements, general control approaches, standard activity programs are reviewed.
8

Sezono įtaka paršavedžių reprodukcijai / The influence of season to the sows reproduction

Galvosaitė, Viktorija 19 March 2008 (has links)
Apibendrinant literatūros apžvalgoje minėtus faktus yra aišku, jog mokslas įsiterpia į tiriamą problemą. Straipsnių, susijusių su reprodukcijos sutrikimų tyrimais, skaičius nuolat didėja. Galbūt dėl to, kad ES skiria daug dėmesio žemės ūkio plėtrai, galbūt konkurencingumas verčia ūkininkus nemažai lėšų skirti tyrimams, susietiems su reprodukcijos problemos išaiškinimu ir jos panaikinimu. Tyrimai atliekami visame pasaulyje, o atskirus rezultatus bandoma susisteminti, keliant įvairias hipotezes. Su ūkiu susijusios problemos sprendžiamos pasitelkiant architektus ūkio planavimui, oro ventiliavimo ir kondicionavimo, apšvietinimo bei kitus specialistus. Tačiau kaip stengiamasi išvengti problemų jų nuolat atsiranda. Iš išskirtų faktorių, įtakojančių paršavedės reprodukcinį pajėgumą, sezoniškumas yra bene svarbiausias elementas, o su juo susiję sutrikimai kelia nemažai diskusijų. Pagal gautus tyrimo rezultatus galime teigti, kad vasarą, esant aukštoms temperatūroms bei ilgam šviesos režimui, būtina keisti ūkinio pastato konstrukcijas, kad neužtrūktų kiaulaičių brendimo laikas. Sėkmingai reprodukcijos eigai keliami dideli reikalavimai: reikalingas kompetetingas personalas, aplinkos veiksnių kontrolė, dokumentavimas bei protokolavimias, atsakingumas ir kruopštumas. Apžvelgiant tyrimų rezultatus pagrindiniai paršavedės reprodukcinių savybių rodikliai žiemos sezono metu buvo geresni nei vasaros (vislumas 4,36 proc., pieningumas 7,7 proc., nujunkomo lizdo masė 8,57 proc. didesni)... [toliau žr. visą tekstą] / Summarizing the facts mentioned in the literature review it is obvious that science intervenes to the researched problem. The number of articles where the disorders of reproduction are researched is increasing. The reasons can be the big attention from EU to the development of agriculture, the fact that competitiveness makes the farmers to spend quite a lot of money on researches where the problems of reproduction are being explained and the ways to eliminate it are proposed. The researches are done all over the world and separate results are systemized, various hypotheses are being formed. Farm related problems are being solved with the help of architects to plan the farm, as well as the specialists of air ventilation and conditioning, illumination and other fields. But even if we try to avoid problems they occur. Among the highlighted factors influencing the reproduction capacities of sow, factor of seasons is almost the most important element, and the disorders related with it raise a lot of discussions. The light regime virtually doesn’t affect the reproduction capacities under the high temperature, so the heat stays the main reason of summer time infertility. Talking about the influence of seasons to the interval of weaning until the rutting it can be stated that in the optimal combination of air temperature and photoperiod, the reproduction capacities can be stimulated; however each factor separately can inhibit the reproduction. The results of this research shows that... [to full text]
9

Genominės DNR metilinti regionai / Genomic DNA methylation region

Stacevičius, Domas 07 April 2008 (has links)
Darbo tikslas: Apžvelgti ir apibendrinti ankstesnius tyrimus apie genominės DNR metilinimą bei šio biocheminio proceso svarbą gyvam organizmui. Darbo uždaviniai: Išanalizuoti ir apibendrinti esamą mokslinę literatūrą apie:1. DNR metilinimo bazinius aspektus. 2. DNR metilinimo procesų eigą. 3. DNR metilinimo biologinę esmę ir reikšmę. 4. DNR metilinimo procesus eukariotuose ir prokariotuose. 5. DNR metilinimo tyrimo metodus. 6. DNR metilinimo duomenų bazes. Darbas paremtas įvairių autorių anksčiau publikuotais duomenimis apie DNR metilinimą ir jo biologinę reikšmę. Surinkta, išnagrinėta ir apibendrinta literatūra apie DNR metilinimą leidžia geriau suprasti ir papildyti žinias apie DNR metilinimo reikšmę ląstelių diferenciacijai, apsaugai, genų represijai ir indukcijai, nukleotidų pasikeitimui genome bei organizmų evoliucijai. Išvados: 1. Metilinimas yra svarbi DNR modifikacija., nuo kurios priklauso svarbūs genetiniai reiškiniai – genomo imprintingas ir apsauga, chromatino sandara, ląstelės ciklo ir genų veiklos valdymas. Metilinimo procesas labai svarbus embriogenezės ir organizmo vystymosi metu, nes nuo jo priklauso genų ekspresija. 2. Citozino likučių metilinimas katalizuojamas fermentais - DNR metiltransferazėmis, kurie randami prokariotuose ir eukariotuose. 3. Metilinimas atlieka ir kitas funkcijas: dalyvauja replikacijos tikslumo kontrolėje, de novo metilinime, taip pat demetilinimo procesuose. / To view and generalize previous analysis about genomic DNA methylation and stress out of this biochemical process to the alive organism. Fit up, analyse and generalize scientific literature about: DNR methylation fundamental dimensions, DNR methylation process, DNR methylation biological point and consideration, DNR methylation process in eukariotics and prokaryotics, DNR methylation exploratory methods, DNR methylation databases. Methylation is an essential DNA modification, whose over depend important genetic expressions – genomic inprinting and conservancy, chromatin structure, cell cycle and repression of genes activity. Methylation process is very important during embryogenesis and organism evolution, because its over depend gene expression. There are three DNA methylation conditions: non-methylated site, methylated site and hemi-methylated site. Methylation investigation was navigate in germ. Parent methylation function in germ is a mechanism, which protects a cell from extraneous DNA institution.
10

Veršelių skirtingo girdymo ir laikymo įtaka jų augimo spartumui / The influence of the different watering and keeping of the calves to the quickness of their growth

Anužienė, Aušra 30 June 2008 (has links)
Darbo tikslas: Išsiaiškinti koks augimo spartumas pasiekiamas girdant veislines telyčaites pienu ir pieno pakaitalu, nustatyti jų kūno išsivystymo skirtumus ir išsiaiškinti, individualaus ir grupinio laikymo įtaką telyčaitėms. Bandymas buvo atliktas 2006 m. spalio–gruodžio mėnesiais, ŽŪB “Bernatoniai“ Kauno rajone. Bandymui buvo atrinkta 20 holšteinų veislės telyčaičių, kurios susirtytos į keturios grupės po 5 telyčaites. Dvi telyčaičių grupės laikytos individualiuose gardeliuose, kos dvi grupės – grupėmis. Iš kiekvienos grupių poros viena telyčaičių grupė buvo girdoma natūraliu šviežiu pienu, o kita – CELTILAIT FITMILK pieno pakaitalu. Pirmomis amžiaus dienomis visos telyčaitės gavo krekenų ir Hokostar vitaminų. Nuo 4 amžiaus dienos visos telyčaitės gavo neribotai, AB “Kretingos grūdai“ veršelių startinio kombinuotojo koncentruotojo pašaro ir šieno. Telyčaičių kūno masės ir išsivystymo kitimas buvo nustatomas jas sveriant ir matuojant atelyčaičių suvartotų pašarų apskaita. Telyčaičių priaugimas buvo nustatomas jas sveriant gimus, o vėliau kas dvi savaites. Tuo pat metu jos buvo matuojamos ir nustatomas jų išsivystymo kitimas. Bandymo metu gauti rezultatai parodė, kad telyčaičių laikomų grupėmis ir individualiuose gardeliuose vystymasis buvo skirtingas, įtakos turėjo ir girdomas produktas. Sparčiausiai augo ir geriau vystėsi grupėje laikytos ir natūraliu pienu girdytos telyčaitės. Jų prieaugis per bandomąjį laikotarpį buvo vidutiniškai 0,486 g (pakaitalu girdytų – 0,465 g)... [toliau žr. visą tekstą] / Goal of the paper: To clarify how quick growth can be achieved watering calves with pedigree heifer milk and milk substitute, to determine the differences in their body development and to find out the influence of individual and group keeping to heifers. This experiment was performed during October-December 2006, at UAB “Bernatoniai”, Kaunas region. 20 heifers of Holstein pedigree were selected for this experiment; they were divided into four groups of five heifers. Heifers from two groups were kept in separate stalls and the other two groups were kept in groups. One of these two groups of heifers was watered with natural fresh milk, and the other group – with milk substitute “CELTILAIT FITMILK”. During the first day of their lives, heifers received first milk and “Hokostar” vitamins. Starting from the forth day of their lives, all heifers were given starting combined concentrated feed of AB “Kretingos grūdai” and hay without any restrictions. The alteration of the heifers’ body mass and development was determined by weighting them and performing the accounting of the feed, consumed by heifers. The gain of heifers was determined by weighting them when they were born and every two weeks. At the same time they were measured and the alteration of their development was determined. The results, achieved during this experiment, showed that development of heifers kept in separate stalls and in groups differed; also it was influenced by the watered product. The most rapid... [to full text]

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