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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.
101

Vliv polymorfismu kandidátního lokusu na technologické vlastnosti mléka

VAŇKOVÁ, Adéla January 2019 (has links)
The aim of this diploma thesis was to investigate the influence of milk betacasein locus (CSN2) polymorfic variants on production characteristics and milk technological qualities in Czech Simmental cattle and Holstein cattle. DNA extracted from milk of 702 cows was genotyped using PCR and RFLP methods. The genotypes A1A1, A1A2, and A2A2 had the following distribution within the population studied: A1A1 in 11,40 %, A1A2 in 8,46 %, and A2A2 in 50,14 % cows. The studied milk parameters were the milk yield (kg), protein and fat percentage and protein and fat yield (kg). The statistical evaluation was made STATISTICA 12 program. We found no statisticaly significant influence of CSN2 genotype on the selected milk yields. The results might be biased by the relatively low amount of individuals studied. Research will continue within the QJ1510339 and GAJU028/2019/ Z grant.
102

Polymorfismus vybraných enzymů jako faktor ovlivňující složení mléčného tuku / Polymorphism of some enzymes as factor affecting milk fat composition

KLOJDA, Martin January 2019 (has links)
The aim of this diploma thesis was to determine allele and genotype frequencies for g.10329C>T (A293V) polymorphism in the SCD1 gene in dairy cow populations, establish effects of this locus on milk production traits and fatty acids composition. At first, allele and genotype frequencies were determined. Subsequently the effect of this polymorphism on milk production traits was proved and effects of this polymorphism were demonstrated as well. For the determination allele and genotype frequencies the PCR/RFLP technique was applied. In this diploma thesis the effect of polymorphism g.10329C>T (A293V) on milk production traits was demonstrated as well as the effects of this polymorphism on fatty acids composition. The findings following from this diploma thesis show economical and health benefits of this SCD1 locus.
103

Vliv teploty vzduchu ve vazné stelivové stáji na chování dojnic

Hladíková, Michala January 2014 (has links)
This thesis deals with the behavior of dairy cows in the stable binding litter depending on the internal temperature of the stable order of lactation , milk production and udder . At the time of observation was recorded every hour position cows - standing , lying on the left or right side . When observations were also measured air temperature , as a major influence on the behavior of dairy cows. The observations took place in 2013 from the month of July to December , twice each month. A total of 12 observations took place . Observation was carried out in the same place as when undergraduate work, four-row barn type K174 breeding cows of Holstein cattle in the farm production cooperative Mezilesí Krakovany. The observed values were then processed with the measured temperature data from monitoring performance , with data on the state of the mammary gland and evaluated in Excel 2007, and the 10th Statictica cz During the evaluation , there were no significant value , which would affect the behavior of dairy cows . The cows were found is in the range of optimum temperature . The effect of lactation on standing and lying cows , showed only performing more frequent lying down and getting up in dairy cows at first lactation. Udder on dairy cow behavior was demonstrated. Show only the preference of the left side while lying down.
104

Chovatelská analýza úrovně chovu skotu ve vybraném zemědělském podniku / The analyse of cattle breeding in an enterprise - case study

HORA, Ondřej January 2014 (has links)
This work deals with an analysis of breeding cattle in the agricultural cooperative Agra Březnice u Bechyně. Data on milk production and reproduction was obtained from records of performance tests and livestock records. The results of performance and reproduction in the years 2010 to 2012 shows that the monitored breeding achieved when compared to the average population of Czech Pied cattle bred in the Czech Republic, above-average values. The efficiency of milk production in the reporting period increased by an average of 394 kg. Milk composition is at the population level. The fat content was in the period, on average, 0.02% lower and the protein content was about 0.01% lower than the values of the population in the Czech Republic. The reproduction of purebred breeding is used in a closed herd turnover. The reproductive performance achieves significantly less value than the population average length of service period. The other reproductive indicators, with the exception of insemination index reached in the period better values than the average of these values achieved in the Czech Republic. The results showed that the most common reason for withdrawal from dairy herds are problems with disease of the legs and udder disease. These problems need to be addressed in the short term better approach to monitoring and prevention in the long term appears to be the most important completion of a new barn. The breeding value of bulls used in reproduction was satisfactory level.
105

Analýza vybraných vlivů na reprodukci dojnic u stáda holštýnského skotu / Analysis of selected effects on reproduction of dairy cows in the herd Holsteins

JEŘÁBKOVÁ, Vendulka January 2014 (has links)
This work shows that the level of reproduction is influenced primarily by management reproduction. Selected indicators reproductions reached cows of the Holstein breed below-average values u (service period, pregnancy after first insemination and insemination index) to average values (interim) and achieve the goals set out indicators breeding Holstein cattle in lactation. Recommendations for breeders is to improve search říjících the cows. Further improve the diagnosis of pregnancy in cows inseminated. Improve the overall management of the herd reproduction.
106

Ukazatele užitkovosti a plodnosti pastevně odchovaných jalovic / INDICATORS OF MILK PRODUCTION AND FERTILITY BY GRAZING REARED HEIFERS

PALČISKOVÁ, Barbara January 2015 (has links)
The aim of this thesis was to evaluate the parameters of the milk performance, reproduction indicators and health of Holstein cows that were raised on pasture at ŠZP (School agriculture company) Haklovy Dvory. Monitoring is carried out in the years 2011 - 2013. The work involved two groups bred cows grazed in total 56. In 2012 it was 27 cows and in 2013 29 cows. The control group which was represented by 20 heifer which had been reared in stable in years 2010-2011 the number 20 Holstein cows. The evaluation of parameters was set on the first standardized lactation in the range of 240 to 305 days. Into observation of reproductive indicators was included the age of the first calving (days), insemination interval (days) and servis period (days). From the productive indicators there was the quantity of milk (kg), the content of fat in the milk (%), quantity of fat in the milk (kg), and the content of proteins.
107

Analýza užitkových vlastností pomalu rostoucího kuřecího hybrida / Analysis of use characteristics of slow growing chicken hybrid

DUPAL, Jan January 2015 (has links)
The main aim of the diploma thesis was to analyze the use characteristics of chicken hybrids with slow growth rate. Following hybrids were analyzed: combination of JA 757, who were fed until 49 days of their age and combination of Pac JA with feed length of 56 days. The average live weight of hybrid combination JA 757 was 2 169 g, the feed consumption per kg of weight gain averaged at 2 119 g and the selection rate reached 0.5%. The combination Pac JA reached live weight at slaughter date of 2 109 g, the feed consumption was 2 366 g and 0.88% chickens was selected. The value of Production Efficiency Factor was higher for the hybrid JA 757 (208) compared with the hybrid Pac JA (158). It was found out that the carcass yield of the hybrid JA 757 was about 3.8% higher (74.7% vs. 70.9%) compared to the hybrid Pac JA. Similarly the weight of the breast muscles reached the weight of 405 g in case of the JA 757 which was 53 g more than in case of the Pac JA (352 g). The leg muscle difference was 132 g in favor of the JA 757 (499 g vs. 367 g) while the weight of abdominal fat was lower by 5.5 g (44 vs. 49.5 g). Therefore it can be stated that the difference was statistically highly significant. Furthermore it was found out that cocks reached higher breast and leg muscle weight than hens of both hybrids. The difference was 33 g and 106 g for JA 757 hybrids and 57 g and 79 g for Pac JA hybrids respectively. Also here the difference was statistically highly significant and statistically significant respectively. Overall the hybrid JA 757 proved to have higher genetic potential in intensity growth and also in carcass utility.
108

Vliv vybraných faktorů na plodnost a dlouhověkost dojnic holštýnského skotu / Influence of selected factors on fertility and longevity of cows of Holstein cattle

KAUTSKÁ, Jitka January 2015 (has links)
This thesis deals with the influence of level of yield, causes putting out dairy cows from the breed and age at first calving on fertility and longevity of dairy cows of Holstein cattle in the agribusiness Agropodnik Košetice, a.s. Monitored indicators of dairy cows of Holstein cattle were the amount of milk in the first lactation in kg, functional longevity in kg of milk, functional longevity in days and the causes of elimination of dairy cows from the breed. From the results of monitored herd it can be concluded that prolongation of age at first calving will increase functional longevity in days statistically significantly. In contrast, there was not found statistically significant effect of age at first calving on functional longevity in kg of milk. Ascertained results of the monitored dairy herd did not confirm that increasing milk yields deteriorated reproductive indicators. The length of the service period was shortened statistically significantly with increasing the yield of milk in kg per one hundred days ((P 0,05), with the yield for the first entire lactation (P 0,001) and the order of lactation (P 0,001). In the monitored herd the dairy cows that were eliminated due to postpartum paresis (2570.70 days) reached the highest longevity and also reached the highest milk production for functional longevity in kg of milk (49,919.95 kg).
109

Posouzení úrovně výživy ve vztahu k produkci mléka u dojnic / Assessment of the Level of Nutrition and its Relationship to Milk Production in Milk Cows

HORKÝ, Jan January 2015 (has links)
In the ZD Kojčice cooperative farm, a stable in Krasíkovice was studied in 2013 and 2014. The farm's production technology and the quality of the ensiled feed, feeding techniques, composition of the feed portions and selected milk production indicators were examined. The economy of milk production was also assessed. The production of ensilage ensured quality feed that was the basis for the milk cows' feed portions. The results show that the feed portions were well balanced in comparison to the recommended nutritional values for milk cows. The average yield in 2014, unlike 2013, decreased by 146 l to 5 960 l per milk cow per year. The costs per feed day were established at 138,2 Kč. The average costs for one liter of milk were 8,75 Kč/l.
110

Dynamika růstu králíků vybraných plemen / Growth dynamics in selected rabbit breeds

POUSTKA, Milan January 2015 (has links)
The aim of the thesis was performance comparison of selected populations of three breeds of rabbits, the Moravian Blue (Mm), the Viennese Blue (Vm) and the Dutch rabbit (Ho), that is a large, a medium-sized and a small breed. The monitored aspects were the production characteristics (gain weight and carcass yield) and the reproductive characteristics (the average number of kits born, the number of all kits born, the number of live born and stillborn and successfully weaned kits, the rate of successful pregnancies, the milkness of the doe). The population of each of the breeds was monitored in a selected base of 68 litters of the Mm, 65 litters of the Vm and 84 litters of the Ho. The weight gain of rabbits was monitored in regular intervals from birth until the end of fattening, i. e. until 8 months of age in the Mm and the Vm and until 6 months of age in the Ho. The results were compared with the weight gain required by the breed standard. Based on the observed weight gain, a growth curve has been created using the Richards function in Excel and Statistica 12.0. The monthly weight gain of the monitored breeds was compared. The highest average gain in weight for the Mm was 693 g, for the Ho 480g and for the Vm 539 g. The results show a significantly higher gain in weight throughout the growth period of the Dutch rabbit than is required by the breed standard. The Moravian Blue showed a lower average increase in weight during the first five months of age than is required by the breed standard. High statistical dependence (R = 0,94, p < 0.01) between weight gain and the number of kits per litter was observed during the first month. From the second month dependence get lower. Since the third month of age, this dependence could not be proven. Based on the parameters of the growth curve, the inflection point of growth was established at 59.8 days and weight 1 528 g for the Mm, at 43.2 days and weight 895 g for the Ho and at 67.7 days and weight 1512 g for the Vm. The average number of kits per litter was 6.3 for the Mm, 6.48 for the Ho and 6.23 for the Vm. The milkness was calculated according to the weight of the litter at 2 and 21 days of age. The milkness for the Mm was 3 985 g, for the Ho 2 582 g and 3 176 g for the Ho. A significant statistical dependence (R = 0.97 0.98) between the number of kits in the litter and the milkness was found. The mortality rate was at a low level for all monitored breeds, with the highest (5 per cent) for the Vm , followed by 2.9 per cent forthe Ho and 1.4 per cent forthe Mm. Analysis showed the highest carcass yield for the Dutch rabbit (62.4 per cent), but a lower live weight gain. The carcass yield was 59 per cent for the Vm and only 56.1 per cent for the Mm. Overall, the results of the thesis show a bigger live weight gain in case of the Moravian Blue rabbit provided there are higher demands for housing and feeding. Its progeny shows a greater growth potential and, in some aspects, also better reproductive characteristics. On the other hand, the Dutch rabbit paradoxically reached a higher number of kits per litter and better carcass yield, giving meat of greater quality. The Viennese Blue rabbit had a slightly higher mortality rate than the other breeds but also a relatively large weight gain and carcass yield approaching other medium-sized meat breeds. The results of the thesis can be beneficial for novice breeders in helping them choose the right breed, as well as for existing breeders in helping them improve the strengths and eliminate the weaknesses of these breeds.

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