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Vliv tělesné kondice dojnic na hladinu ketolátek v krvi
BEŇASOVÁ, Veronika
The aim of this diploma thesis is to evaluate the data about holstein dairy cow body condition at calving and to review its effect on ketones blood level and its relation to incidence of ketosis. The monitoring took place in a selected dairy farm from October 2017 to February 2019. Body condition of 280 cows was evaluated on the day of calving by assessing the body condition score (BCS) and later on 10 days in milk the blood level of B-hydroxybutyrate was measured. Furthermore, parity, body weight in calving day, body weight on 10 days in milk, content of milk fat and protein on 10 days in milk and milk yield on 10 days in milk were monitored. Average BCS of the herd was 3,7, the maximum measured BCS value was 5, the minimum was 2. Total incidence of ketosis on herd level was 21,07 % considering ketosis if BHB 1,0 mmol.l-1. 62,7 % of that was a subclinical form of ketosis while the remaining 37,3 % was the clinical form of ketosis. Correlation analysis of the relation between parity and level of BHB in blood showed positive correlation (r=0,15, p=0,00), when cows on higher lactation had higher level of blood BHB. Positive correlation between fat/protein ratio in milk and level of BHB in blood was evaluated by correlation analysis (r=0,31 , p=0,00). The BCS at calving and BHB level on 10 days in milk showed positive correlation (r=0,14 , p=0,02). As far as negative energy balance is taken into account, the positive correlation between BCS at calving and body weight loss was confirmed (r=0,17 , p=0,00). The fact that heavier cows and cows with higher BCS mobilise more body fat reserves was confirmed by positive correlation between the body weight at calving and the body weight loss (r=0,47, p=0,00) and between the body weight at calving and the fat/protein ratio in milk (r=0,27, p=0,00). Body weight at calving had provable positive impact on the milk yield (r=0,19, p=0,00).
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Vliv tělesné kondice na kvalitu reprodukce a mléčnou užitkovost krav
BRŮŽKOVÁ, Monika
The aim of the thesis was to evaluate the data about body condition of cows and assess the relationship between changes of health status of the mammary gland, milk production and quality of cow´s milk. The monitoring took place in a selected company from October 2015 to September 2016 with the Czech spotted cattle. The body condition scoring was monitored within the herd, with the monthly evaluation of data, during the milking in the morning, together with the production performance control. The data values, received out of production performance control, were used for milk production performance (amount of milked milk, % fat, % protein, % lactose, SCC). Then the data about reproduction of the monitored herd were used, so as the order of lactation, date of the last calving and age. Total of 482 cows were monitored. During evaluation of the condition score, the average level of cows body condition was detected with value of 2, 18. Minimal body condition, during the monitored period, was 1.25, the maximum was 3.75. Correlation analysis of the relationship between the form and amount of the milked milk showed a negative correlation (-0.21). Furthermore the quality of milk was monitored. The amount of fat in milk, within the monitored herd, was 4.16% and 3.63% of protein. The fat was found to be the component, which the cow´s form had the effect on, with value: r = 0.14. The most affected component by the form was protein (0.28). A slight influence of pregnancy with Rf value = 0.06 arose too. Next evaluated indicator of milk quality was somatic cell count (SSC). The influence of the form, on SSC, was moderately significant (-0.05). The average somatic cell count, during the monitored period, was 287.75 thousand per milliliter. The prolificacy within the herd appears to be inconvenient. Within the population of the herd, the herd showed to be better at pregnancy rate after the first insemination (46.7%), however after all inseminations it proved to be weaker (44%). Subsequently the effect of three factors was evaluated: the day of pregnancy, the day of calving and the age in days at form. For dairy cows, at first lactation, there was found one significant influence the age, with the value of the correlation coefficient 0.23, while the cows at higher lactation showed to be influenced by all three of these factors. The dependence between the pregnancy day and the BCS is expressed as a negative (-0.06) but very weak. Higher absolute value of the correlation coefficient was observed between the age, in days, and BCS (-0.14). BCS value was directly proportional to days, since calving (0.16). This thesis was carried out with the support of the project Gaju 019/2016 / Z Nutrition and breeding technology as a way to animal welfare and the product quality.
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