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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.
41

Vliv vybraných faktorů na masnou užitkovost býků zjišťovanou ve stanici kontroly výkrmnosti skotu Želeč / Influence of selected factors on the fattening capacity and carcass values of bulls in the control station Želeč

PUFR, Josef January 2014 (has links)
Cattle breeding is one of the part of traditional Czech agriculture. It is a vital part of economy consisting of two main branches - milk and beef production. Beef is one of the main products of cattle breeding sometimes provided by fattening of heifers, cows and bulls. Producing meat with the highest quality with low costs is the main goal of fattening the cattles. I have tested the influence of selected fators on the fattening capacity and carcass values of Czech Fleckvieh bulls in the control station as well as the economic requirements of the fattening period. I have compared the test period of 530 ? 10 days with period of 610 ? 10 days of fattening using the old and new technology of supplementation. Further fattening was provided by results of growing Charolais, Limousin and Czech Fleckvies x Simmental bulls. The results suggest that the increase of the period of fattening for 80 days had a positive effect on carcass yield (p < 0.001), assigning in the classification according to SEUROP and profitability of farming. The positiv relationships between breeding value of fathers and carcass yield of their sons was observed. Finally, the positive influence of new technology of fattening on the classification acording to SEUROP was shown.
42

Užitkovost a plodnost u plemenic holštýnského skotu / Performance and reproduction of Holstein cattle

KAMENÍKOVÁ, Jana January 2011 (has links)
The aim of thesis was to analyze the milk efficiency and fertility of dairy cows of Holstein cattle breeding under intensive conditions. The examinations were made in the agricultural company ZDV Krchleby, a.s. during the year of 2007 to 2009. In total, 147 dairy cows were used for observation including 35 Holstein dairy cows (100% H, R 100%), in a group called - H1, 70 Holstein cows crossed with Czech spotted cattle (H 75 - 87%, R 75 - 87%) in group - H3 and 42 Holstein cows crossed with Czech spotted cattle (H 50 - 74%, R 50 - 74%), in group - H4. Furthermore, the basic data set was divided according to lactation into four groups: 1st lactation, 2nd lactations, 3rd lactations, 4th and more lactations. The main indicators for evaluation of the milk efficiency were the: milk quantity (kg), amount of fat in the milk (%), production of the fat in the milk (kg), amount of protein in the milk (%), production of protein in the milk (kg), content of lactose in the milk (%), persistency of lactation and lactation duration (in days). In terms of fertility, the following factors were evaluated: the cow?s age at first birth (in days), insemination interval (in days), service period (in days) and the periods between births (in days). The cows in the first group milked on average of 8945.03 kg of milk, the amount of fat was 3.66%, the content of protein was 3.32%. Cows in the second group milked an average amount of 8186.55 kg of milk, the content of fat was 3.77%, the amount of protein was 3.33%. The third group milked an average amount of the milk 8649.05 kg, the content of fat was 3.58% and the amount of protein was 3.26%. Differences between these groups were not statistically significant. From the reproductive indicators, statistically, the only most significant difference was the time in between births. The longest period in between births was measured in the first group - 576.22 days, in the second group - 487.38 days and in the third group - 480.95 days.
43

Vyhodnocení reprodukčních ukazatelů ve vybraném chovu dojnic v ZOD "Podhradí" Choustník

NEZBEDOVÁ, Marie January 2017 (has links)
The aim of this thesis is to evaluate chosen influences on the extent of reproduction of randomly chosen milk cows that are bred in the same conditions. The chosen influences such as breed, age of the first calving, time of year of calving and level of yield were observed within breeds of Czech Fleckvieh and Holstein cattle. Evaluation was carried out in ZOD "Podhradí" Choustník company, specifically in Budislav farm. 191 cows were chosen for the basic sample. 95 of them were Holstein cattle and 96 were Czech mottled cattle. Chosen influences were evaluated according to data gained from the set of milk yield inspections. A statistically significant difference was observed between Czech ticks and Holstein cows in the length of service period per second and first lactation where Holstein cows have a second lactation period longer than 44 days (P <0.001). Evaluation of first calving age did not show any influence on the level of reproduction neither within Czech Fleckvieh nor within Holstein cattle. During the annual evaluation, it emerged that Holstein cows calved in spring and winter have significantly bigger insemination interval compared to cows that were calved during summer or autumn. This fact was also proven by correlation analysis. This analysis also confirmed the relation between annual period and insemination interval Rxy=0,21(P<0,05). The correlation analysis also proved the relation between annual period and service period as well as interim of Czech Fleckvieh cattle Rxy= 0,327 (P<0,01). Statistically significant influence was not proven within Holstein cattle. Correlation analysis only pointed out the relation between yield and service period Rxy=0,213 (P<0,05). Unlike Holstein cattle, gradual increase of service period figures and interim depending on yield was noticed. Breeding cows milking more that 7,5 thousand kg of milk per lactation had service period of 132 days (P<0,01) and interim 407 days (P<0,01). Economical losses caused by prolonged interim during monitored herd of cattle reached 400.490 CZK in year of 2016.

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