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Reprodukční a užitkové vlastnosti dojnic holštýnského skotu v chovech s rozdílným typem dojení
JEŠETOVÁ, Kateřina
This study focuses on the reproductive and productive traits on two dairy farms of Holstein cattle with different types of milking. The aim of the study was to evaluate and compare the productive and reproductive parameters of Holstein cattle in herringbone and robotic milking parlours for the year 2023. On the farm A, there is milking caried out in a herringbone parlour twice a day. Cows are milked by machine in the groups (2×10). On the farm B, milking is carried out by using automatic milking robots twice a day. It is obvious from the milk yield results that the farm B achieved a higher average milk yield by almost 4 liters per cow (3,86 l) compared to the farm A. Cows from both farms achieved higher milk yields with increasing order of lactation. On the other hand, higher milk component content (fat and protein content) was achieved within farm A. There was not a significant difference in the average protein content in the milk between the farms (0,08 %). However, the average milk fat content was higher in the farm A by 0,41 % compared to the farm B. The average somatic cell count was twice as high in the farm with robotic milking (342 000 SB/ml) compared to the farm A (170 000 SB/ml). The largest differences between these farms with herringbone and robotic milking enterprises were in milk yield, milk fat content, somatic cell count, lactation days and percentage of stillborn calves. Other indicators, such as service period, age at first calving, dry period length, intercalving interval and insemination index were similar or almost identical in both farms.
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Výskyt ketóz ve vybraném chovu dojených krav v letech 2020-2022
ŠTĚCHOVÁ, Petra
Ketosis is a disorder of energy metabolism characterised by reduced milk yield, inappetence and weight loss. Ketosis also affects milk composition. The aim of this thesis was to evaluate the incidence of ketosis in a selected dairy cow herd. The incidence of ketosis was evaluated in lactating Holstein cows over a period of three years (2020-2022) in the dairy farm in Žákava. Ketosis was detected on the basis of beta-hydroxybutyrate (BHB) content in the blood of the cows using the FreeStyle Optium NEO device. A BHB value of 1.0 mmol/l or higher was considered as an individual affected by ketosis. A total of 1740 dairy cows were included in the study. Ketosis ocurred at a relatively stable level of 20 %. There were fluctuations in the frequency of ketosis across seasons, as well as fluctuations in the average blood BHB content. The effect of the treatment procedure and the effect of prevention on the incidence of ketosis were also investigated. The treatment success rate was 80.41 % for the study period. Treatment with monopropylene glycol and prodigestane was largely successful. Intravenous glucose administration had a slightly lower success rate. Preventive measures had a positive effect on both the frequency of ketosis and the average blood BHB content. In addition, the presence of ketones bodies in milk, the relation of ketone bodies in blood to ketone bodies in milk and the effect of elevated blood BHB on milk composition were determined according to performance monitoring protocols. Both acetone and BHB contents were increased in milk from sick cows. The levels of ketone bodies in milk are positively correlated with the level of BHB in blood. Increased blood BHB content results in a change of content of individual milk components. The highest difference was found in the fat content, an increase of 4,89 %. Further, the citric acid content increased with the BHB content of the blood and the protein, lactose, non-fat dry matter and urea content decrease.
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Předpoklady realizace reprodukční schopnosti skotu z hlediska podmínek chovu
VACHOUŠKOVÁ, Jana
The objective of this thesis is a creation of an overview of different factors affecting reproduction performance of dairy cattle, obtaining data concerning reproduction performance of dairy cattle and reviewing reproduction performance in the year 2019. Data used in this thesis was gathered in Úněšovský statek, a.s. at farms in Pernarec and Chrančovice. Zootechnological archive and the records of Českomoravský Svaz Chovatelů were used to process the data and the information about the company was provided by Úněšovský statek, a.s. The main focus of the work is observation of the way in which a heat stress affects reproduction performance of dairy cows at Pernarec farm with milk utility of 11 877 kg and dairy cows at Chrančovice farm with milk utility of 12 103 kg. A THI-Cooper meter was installed in stables of mentioned farms in order to monitori temperature and humidity and produce temperature-humidity index values from 10.6.2019 to 14.9.2019. These values showed if/when the stabled cattle experienced heat stress. Results of this observation were later divided into three categories by severity of heat sress. Pernarec farm showed highest pregnancy rate (60%) during the time without heat stress. Chrančovice farm showed highest pregnancy rate (58%) during the time with medium heat sress. The overall results of the measuring imply that high pregancy rate was kept in Pernarec and Chrančovice farms even during high heat stress periods because of synchronization program used.
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The influence of calf mortality on economic efficiency of cattle breeding
SVOBODNÁ, Hedvika
The purpose of this thesis was to analyse mortality in calf rearing.I found out that the most important causes of the calf mortality are: course of calving, order of calving, seasonal character and climatic conditions.The casualties in calf rearing were about 24 %. Economic loss which was evoked by calf death affected trading income in whole cattle breeding. The main aim of the both farms is to achieve high level in calf rearing which essentially decides about profitability and efficiency of cattle breeding.
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