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Metody reprodukce využitelné v chovu masného skotu
Střecha, Filip
This thesis entitled "reproduction methods usable in breed of beef cattle" describes the most commonly used reproductive techniques at herds of beef cattle. Breeders implement the bovine reproduction mostly through natural breeding and insemination. The first part of this thesis is devoted to the breeding of bulls, their selection and bonitation. Further, the effect of a bull in a herd is introduced, its classification and the main principles of bull breeding. In the second part the thesis deals insemination. It describes the creation of an insemination dose, its consequent long-term storage and the insemination of cows. The possibilities of influencing the gender and correct timing of insemination are have briefly summarized. The third section introduces the technique of embryo transfer. It describes a stimulation of superovulation, preparation of donors and recipients, flushing of embryos, long-term preservation of embryos and their subsequent transfer. In the fourth section bull catalogues of the Czech Republic, France and Ireland are compared. The individual parts of the cataloques and differences between them are described there. The last part is the assessment of the individual reproductive indicators published in the Czech Republic. The six largest breeds is compared here, and in some consideration beef cattle is compared across all breeds. We evaluates the length of the interim period with respect to the age of a cow, its age at first calving, the percentage of live born of calves and the part of various systems used during ensuring the the reproduction in the herd.
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Vyhodnocení úrovně zabřezávání skotu na farmě využívající řízené reprodukce stáda
Střecha, Filip
The aim of this thesis was to evaluate the level of mating on the farm using controlled herd reproduction. The evaluation of the level of pregnancy was carried out in dependence on the individual month of observation, the monitored parameters of milk from the performance control of individual lactations and the lines of fathers of cows. Performance data for January 2017 - April 2018 were used for the assessment. Based on the result, it can be concluded that the seasonal percentage is affected by the season. It has been shown that the percentage of pregnancy has decreased in the summer month. The significant decrease in the rate of mating was occurred with the increasing age of cows. The percentage of lactation, regardless of the order of lactation and the line of bulls, is negatively influenced by the milk yield and by the positive effect of the number of lactation days when embedded. To confirm the negative effect of milking yield on the breeding, the NEB breeders showed the highest milk yield and the lowest percentage of pregnancy. Significant fluctuation were occurred in value when evaluating individual indicator depending on the reference month. In the middle of the reporting period, the amount of urea in the milk had a positive effect on pregnancy. A similar result was obtained for the T / B ratio.
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