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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.
21

Untersuchungen zum Energie- und Proteinstoffwechsel sowie zur Fruchtbarkeit bei Milchrindern in Tirol

Andratsch, Magdalena 03 March 2009 (has links)
In der vorliegenden Studie wurde bei Tiroler Milchkühen verschiedener Rassen [Braunvieh (BV), Red Friesian (RF), Holstein Frisian (HF), Grauvieh (GV), Fleckvieh (FV)] hinterfragt in welcher Beziehung Energie- und Proteinstoffwechsel zur Fruchtbarkeit stehen und ob sich signifikante Unterschiede zwischen den Rassen und den verschiedenen peripartalen Entnahmezeitpunkten aufzeigen lassen. Die Untersuchungen erfolgten in 27 Tiroler Milchviehbetrieben an insgesamt 252 Milchrindern (154 BV, 42 RF, 14 HF, 15 FV, 27 GV). Bei allen Betrieben kann eine durchschnittliche Stallfütterungsperiode von 200 Tagen festgehalten werden. Das restliche Jahr verbringen die Kühe auf stallnahen Weiden oder Almen. Insgesamt wurde den Kühen fünfmal Blut aus der Vena jugularis externa entnommen. Die erste Blutprobenentnahme erfolgte im Herbst bei der Einstallung, die zweite 1-2 ante partum (Wo a.p.), dann 2-5 Tage post partum (d p.p.), danach 4-7 Wo p.p. und die fünfte Probe wurde im Frühjahr vor dem Weideaustrieb entnommen. Bei jeder Probe wurde der allgemeine Untersuchungsgang nach BAUMGARTNER (2005) durchgeführt sowie der BCS, und dabei bestehende Krankheiten gegebenenfalls protokolliert. Klinisch-chemisch wurden bei jedem Tier die Parameter freie Fettsäuren (FFS), Betahydroxybutyrat (BHB), Bilirubin (BILI), Cholesterol (CHOL), Gesamtprotein (PROT), Albumin (ALB), Harnstoff (HST), Kreatinin (CREA), Aspartat-Amino-Transferase (AST), Gamma-Glutamyl-Transferase (GGT), Glutamat-Dehydrogenase (GLDH), alkalische Phosphatase (AP) und Kreatinkinase (CK) analysiert (HITACHI 911). Die Tiere wurden für die Auswertung in die unterschiedlichen Rassen und zudem noch in zwei Gruppen eingeteilt, ohne die Rassen zu berücksichtigen, d.h., in „gesund“ und „krank“. Die FFS,- BHB,- BILI,- PROT,- ALB,- HST- und CREA-Konzentrationen sowie AST,- GGT,- GLDH,- und AP-Aktivitäten zeigten zu keiner Zeit signifikante Differenzen bei den verschiedenen Probenentnahmen zwischen gesunden und kranken Kühen. Die CHOL- Konzentration zeigte zum Entnahmezeitpunkt Herbst und 4-7 Wo p.p. signifikante 82 Zusammenfassung Differenzen zwischen gesunden und kranken Kühen. Bei der CK-Aktivität bestanden bei der Probenentnahme Frühjahr zwischen gesunden und kranken Kühen signifikante Unterschiede. Bei den verschiedenen Rassen haben nur die FFS- und BHB-Konzentrationen signifikante Unterschiede gezeigt. Die BHB-Serumkonzentrationen von Milchrindern verschiedener Rasse weisen bei allen Entnahmen, außer bei der Entnahme 1-2 Wo a.p., signifikante Differenzen zwischen den Rassen auf. Bei der Probe Herbst gibt es zwischen HF und den anderen Rassen, außer dem BV, und bei der Entnahme 2-5 d p.p. zwischen BV und RF geringfügige, aber statistisch gesicherte Differenzen. Zum Probezeitpunkt 4-7 Wo p.p. konnte eine deutliche Signifikanz (p≤ 0,05) zwischen RF und GV nachgewiesen werden. Bei der Entnahme Frühjahr weisen GV und BV eine geringfügige, aber statistisch gesicherte Differenzen auf und GV und RF eine deutliche, statistisch ebenfalls gesicherte Differenz. Zwischen den Entnahmezeitpunkten konnten für alle Rassen, außer HF teilweise signifikante Unterschiede nachgewiesen werden. Zwischen den einzelnen Rassen wurde bei der Entnahme Herbst eine deutliche Signifikanz (p≤ 0,05) zwischen den Red Friesiankühen und den restliche Rassen berechnet. Zum Entnahmezeitpunkt Frühjahr zeigen sich signifikante Unterschiede zwischen RF und BV bzw. GV. Zwischen den einzelnen Entnahmezeitpunkten konnten bei allen Rassen Signifikanzen (p≤ 0,05) festgestellt werden. Die BHB- und FFS-Serumkonzentrationen zeigen in Beziehung zu unterschiedlichen Geburtsverläufen, p.p. Erkrankungen, Fruchtbarkeitsstatus und Trächtigkeitsstatus keine signifikanten Differenzen auf. ZTZ und Milchleistung zeigen bei Rindern mit verschiedenen Geburtsverläufen und solchen mit Fruchtbarkeitsstörungen keine signifikanten Differenzen auf. Die ZTZ weist zwischen Rindern ohne Fruchtbarkeitsstörungen und denen mit Stillbrunst, Ovarzysten und C.l. persistens signifikante Unterschiede auf. Außerdem haben Rinder mit Endometritis eine signifikante Differenz (p≤ 0,05) zu Rindern mit Ovarzysten oder C.l. persistens. Die Milchleistung weist signifikante Unterschiede zwischen Rindern ohne Fruchtbarkeitsstörungen und Rindern mit Ovarzysten auf. Generell zeigen die untersuchten Kühe etwas unerwartete Ergebnisse mit fast ausschließlich fehlenden gesicherten Unterschieden zwischen gesunden und kranken Kühen. Ursache könnte der durch die gegebenen Fütterungsbedingungen weniger belastete Energiestoffwechsel sein im Vergleich zu HF-Kühen mit dominanter Maissilagefütterung. Zudem enthält die Gruppe „krank“ auch Störungen, die bekannterweise kaum mit Stoffwechselabweichungen verbunden sind. Weiterhin deuten sich rassebedingte Unterschiede gegenüber den HF-Kühen an.
22

The effect of Fleckvieh crossbreeding in dairy cattle on the conjugated linoleic acid content of milk produced in intensive and pasture-fed systems

Sasanti, Babalwa January 2015 (has links)
Thesis submitted in fulfilment of the requirements for the degree of Magister Technologiae: Agriculture in the Faculty of Applied Sciences at the Cape Peninsula University of Technology / Conjugated linoleic acid (CLA), a fatty acid (FA) present in the meat and milk of ruminant animals, is considered a functional nutrient for humans. The interest in CLA is attributed to its many health benefits, such as having anti-carcinogenic, anti-atherogenic, anti-diabetic and anti-adipogenic effects. Dairy products are a rich natural source of CLA, and preliminary research indicates that the levels in milk can vary based on cattle breed and feeding system. The Fleckvieh is a popular dual-purpose breed recently introduced to the Western Cape. It is used in crossbreeding programs with Holstein and Jersey herds to increase fertility and beef production. Holstein and Jersey cattle are the two most common South African dairy breeds, but little information is available on the effect of crossbreeding on FA content and CLA levels in the milk. The primary objective of this study was to compare milk FA composition and CLA content of these two dairy breeds and their respective Fleckvieh crosses. A second objective was to investigate the effect of lactation stage on CLA levels. Jersey (J) and Fleckvieh x Jersey (F×J) cows were kept in a pasture-based system (PBS) for the duration of the study. Holstein (H) and Fleckvieh x Holstein (F×H) cows were housed in a feedlot system and fed a total mixed ration (TMR) for the duration of the study. The FA and CLA content of feeds from these two feeding systems were also analysed and compared. All cows used in the study were housed at the Elsenburg Research Farm of the Western Cape Department of Agriculture. Milk samples were collected every 35 days from the cows in each feeding group, starting 10 days after calving. Samples were kept in a freezer at -20 °C until laboratory analyses. The total number of milk samples collected was 1044. The milk FA composition and CLA in particular were determined by gas chromatography. Differences between groups were statistically analysed by two-way repeated measures of analysis of variance (ANOVA). Results show that milk CLA levels are higher in Fleckvieh-crossbred cows when compared to purebred cows. The higher CLA content of milk from Fleckvieh crossbred cows demonstrates the feasibility of using Fleckvieh bulls in South African crossbreeding programs, and are also an indication that genetic selection for increased CLA content is possible. The analysis of lactation stage showed that milk CLA is higher during late lactation. A comparison of feed samples from the two feeding systems revealed that pasture feeding resulted in higher omega-3 FA in milk. Key words: Conjugated linoleic acid, milk fatty acids profile, diet, breed, health benefits, Fleckvieh, Holstein, Jersey, diet, pasture based system, total mixed ration system,
23

Vybrané vlivy na mléčnou užitkovost dojnic u českého strakatého skotu

POKORNÁ, Lucie January 2019 (has links)
The diploma thesis "Selected factors on milk utility of Czech Fleckvieh dairy cows" deals with certains effects on selected cattle herd, which are detected from milk utility control. The author compares dairy cows within first and third lactations in all cases. Overview of used literature is selected into specific chapters, in first part the Czech Fleckvieh is defined with its history, characteristics, related breeds and breed utility. Another comprehensive chapter is devoted to milk utility, lactation and selected factors on animal utility. Last part of literature overview is devoted to reproduction and reproductive indicators. Second main part, which is called material and methodology, author deals with cattle herd in Jasanka s.r.o. company, judging and assessing selected factors with help of milk utility control results. Collective results are assessed through statistics.
24

Vliv vybraných faktorů na užitkovost a dlouhověkost dojnic u stáda českého strakatého skotu

KŮSOVÁ, Hedvika January 2015 (has links)
The aim of this study was to evaluate of selected factors on milking yeild and longevity of Czech Fleckvieh cattle. There were monitored the indicators of the amount of milk for the first lactation in kg, the lifetime performance in kg, the age at the first calving, the functional longevity in days, the lenght of the service period, the lenght of the meantime days, the live weight in kg, the elimination of the causes from the breed. 273 culled cows were included. The relationship between some of the observed factors were signifiant such as the amount of milk yeild on the first lactation and the lifetime performance. In the opposite, there was no signifiant relationship between the age at the first calving and the functional longevity. The milk performance at first calving has been increasing with the age.
25

Vliv úrovně odchovu a věku při prvním otelení na výkonnost a dlouhověkost dojnic českého strakatého skotu

VAFEK, Jan January 2016 (has links)
The set includes 1782 heads of culling Czech fleckvieh cattle eliminated from 1 January 2012 to 1 September 2015. Influences on the first calving age, calving interval and lifetime milk yield were detected for data in the set. The following items were integrated among selected lifetime milk yield influences : genotype, herd, first calving age and first calving month. It was also tested whether the age of the first calving of milking cows is influenced by genotype and a herd. The last tested hypothesis was related to the influence of genotype and a herd on the length of the carving interval. The influence of genotype, lactation and the age of first calving cows on the way of elimination was investigated in the set as well. Multi-factor analysis of variance were used for the calculation of differences among the individual tested groups . With respect to statistical significance there was a statistically significant effect (p <0.05)of the herd and genotype on the age of the first calving cows found out. From the set it is evident that cows calved earlier reached better lifetime milk yield than cows calved at the older age (p <0.05). Another statistically significant difference (p <0.05) was found out within the first month of calving. Milking cows calved during colder periods of the year reached the higher lifetime milk yield. The influence of genotype on milk yield was not proved in this set. This also holds to reproductive parametres, there was no influence of genotype and the age of first calving on calving interval. When observing the outcome in terms of how we can positively evaluate the elimination of voluntarily culled milking cows, which is 34% .This situation is significantly lower than it is stated in literature and shows a good zootechnical care of the herds. In terms of elimination method there were the most dairy cows culled because of fertility - 31%. This fact shows that fertility is one of the main factors influencing the managament and profitability of dairy herds of cattle.
26

Ekonomická analýza produkce mléka u dvou užitkových typů skotu

DAŇHELOVÁ, Lenka January 2016 (has links)
The aim of thesis was to conduct evaluation of milk yield and fertility indicators of Czech Flecvieh cattle and Holstein cattle breed which were kept in chosen agriculture company and to determinate a possible difference of milk production costs between individual productive types of the cattle. Data used to create this thesis was from agriculture company STAGRA, spol. s r.o. which breeds dairy cattle. According to specified thesis goals dairy performance indicators (kilograms of milk, % and kg of fat, % and kg of proteins) and fertility indicators (first calving age, calving interval duration) were assessed separately in Heřmaneč cowshed (H2 Holstein cows, 210 pcs.) and Skrýchov cowshed (H1 Holstein cows, 24 pcs. And C1 Czech Fleckvieh cows, 59 pcs.). Milk performance and fertility indicators were evaluated for control year 2014/2015. Cost items of dairy cattle breeding were obtained from accouting of the calendar year 2014. Due to operational reasons only two cowsheds were observed Heřmaneč with Holstein breed (H2) husbandry and Skrýchov were Czech Fleckvieh cows (C1) were dominant. Data files were processed by relevant statistical methods. It was found that H2 group dairy cows reached the highest milk yield (10 395.17 kg) with average calving interval of 369 days. On the other hand Czech Fleckvieh cows reached the highest protein (3.64 %) and fat (4.16 %) content in milk. H1 group dairy cows reached lowest calving age (25 month and 18 days). The milk production cost comparison within observed productive types showed that costs per 1 l of milk were higher in the Skrýchov cowshed, on the contrary feeding day costs were higher in Heřmaneč cowshed.
27

Vliv genotypů pro gen leptin na vybrané kvalitní ukazatele hovězího masa

BENEŠ, Karel January 2017 (has links)
The dissertation "The Influence of Genotype of Leptin Gene on Qualitative Characteristics of Beef" describes the effect of polymorphisms of gene of leptin on selected qualitative, morphometric and weight indicators of beef and carcass. The analysis was carried out on 333 bulls of Czech Fleckvieh, which were genotyped (by PCR/RFLP method) of chosen locus. This locus is associated with qualitative changes in beef according to previous foreign studies. The weight of carcass, fore and hind quarter of the right half of the carcass, the weight of the individual tissues (meat, bone, and fat) and the weight of main meaty parts from the right half of carcass were measured. Before the dissection chosen morphometric indicators were measured. After the dissection, a sample of the musculus longissimus lumborum et thoracis was taken and then analysed in the laboratory. Basic chemical composition (dry matter, fat content, protein, and ash), muscle fibers diameter and fatty acid profile was determined. In addition, pH, added water holding capacity, colour (CIE Lab colour coordinates) were analysed both for one-day post-mortem and after 14 days of ageing. The shear force (using the Warner-Bratzler probe) was evaluated at the same time intervals as for both raw and heat-treated samples by grilling. The studied LEP polymorphism had a statistically significant effect on the weight of the hot carcass, the weight of right half of carcass and fore and hind quarter. LEP polymorphism significantly affected the proportion of meat on the right half of carcass, the weight of the bones and total weight of the I. class meat, and the weight of the I. class meat in the fore quarter. Further, the effect of LEP polymorphism on the weight of boneless round, boneless chuck, plate, flank, rib, hind shank, and meat trimmings of fore quarter was found. In a group of morphometric indicators, the effect was significant on lengths of round, fullness of round and round circumference. In the case of chemical composition, the effect of LEP polymorphism on the intramuscular fat content was significant. From the qualitative indicators, the effect was significant on the pH value and added water holding capacity, both one-day post-mortem and after 14 days of ageing. In the case of tenderness, the effect on shear force of heat treated, non-aged meat was significant. From the indicators describing colour, a statistically significant effect on the indicator of lightness was found in the case of unconditioned meat and after 14 days of ageing the effect was significant on the indicator characterising yellow colour and the colour saturation. Determination of fatty acid profile was carried out by gas chromatography. The effects of studied polymorphism and differences between LEP genotypes were found in myristic, palmitic, palmitoleic, linoleic, -linolenic, -linolenic, conjugated linoleic, eisocapentaenoic, docosatetraenoic, docosapentaenoic both n-6 and n-3 and docosahexaenoic acids. From aggregated indicators, the statistical significant effect of LEP polymorphims on PUFA content, omega-3 fatty acids content, and omega-6/omega-3 fatty acids ratio was found. In connection with other candidate gene loci influencing the quality of beef, the results of dissertation can be used in the preparation of breeding schemes aimed at the production of quality breeding animals, highlighting the higher quality standards of the produced meat.
28

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.
29

Ableitung der Wirtschaftlichkeitskoeffizienten und optimalen Indexgewichte des Gesamtzuchtwertes für die deutschen Milch- und Zweinutzungsrassen unter Berücksichtigung aktueller und erwarteter zukünftiger Rahmenbedingungen / Economic values and index weights for German and Austrian dairy cattle under current and expected future conditions

Lind, Bianca 19 July 2007 (has links)
No description available.
30

Analýza reprodukce a mléčné užitkovosti vybraného stáda mléčného skotu / Analysis of reproduction and milk yield of dairy cattle

STEJSKAL, Petr January 2016 (has links)
The diploma thesis is focused on reproduction and milk yield of a herd of Czech Fleckvieh and Red Holstein cattle on Velká Chyška farm. Milk yield together with the reproduction makes a basement of every breeding and its analysing is very useful for the breeder. The aim of the thesis was to split the herd according to the lactation into four groups (1, 2, 3, 4 and more lactations) and according to the percentage of blood of Czech Fleckvieh and Red Holstein cattle into three groups (C1- C 75-100 %, C2- C 51-74 % and R- R 51-100 %). To observe the indicators of milk yield and especially to observe yield in standardized lactation, index of persistence of the lactation line and whole-life yield of these cows. Next, to focus on the reproductive indicators: the insemination interval, the service period and the interval itself. Gathered information was recorded into tables and then statistically evaluated. Also, all groups were mutually compared. Needed information was gathered from GEA Dairy plan program and the milk cow cards. Milk cows, which started the lactation in period from 10. 10. 2014 to 30. 2. 2015, were included into the analyzed group. Generally, 155 pieces of livestock participated here. The milk yield indicators were evaluated as excellent. The groups of cows C1 and C2 cows with dominant percentage of blood of Czech Fleckvieh breed, showed significantly better-than-average results when compared with the yield check. The group with dominant percentage of blood of Red Holstein breed (R) exceeded the results from the yield check of the Czech republic as well, but not as in such extent as in case of C1 and C2 groups. In comparison of the groups together, no statistically important results were found. Statistically, only influence of lactation order to the yield in standardized lactation and also influence of lactation order to the index of persistence of lactation line was proved. Reproductive indicators were different in comparison from the yield; they were on very low levels. The service period and the period itself were evaluated as unsatisfactory in all groups and a problem with reproductive management was proved. In comparison of the groups together, no statistically important differences were found as well. Based on the found results and their analysis, conclusions for the breeding practice came about.

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