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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.
1

Zhodnocení reprodukčních ukazatelů ve stádě skotu / Evaluation of reproductive parameters in a herd of cattle

Blatský, Jaroslav January 2016 (has links)
The aim was to evaluate the reproductive performance of the dairy herd. Data were obtained on the farm ZZN Strakonice center Sousedovice from cows culled during 2015. The center treats an average of 250 cows that are kept free of manure and farm milked at four milking robots Lely - Astronaut. The most important reproduction traits were summarized and subsequently statistically processed. Monitored were fertility parameters, milk yield and lifetime production, which were derived from a zootechnical records and monthly reports from milk recording system on 100 dairy cows. With increasing milk yields were deteriorating reproduction parameters such as artificial insemination index, insemination interval and number of days open. For the entire group of cows was monitored milk productivity and reproduction parameters related to parity. The average milk yield in the selected cows was 8579 kg of milk per lactation. With parity increased milk yield per lactation. As well as the average daily milk production and average milk production per day of calving interval. Insemination index and days open length were significantly longer for 2nd lactation where a large increase in milk yield negatively affected these parameters. Furthermore, we evaluated the lifetime milk production. The highest average yield per lactation reached cows cullet later than on 4th lactation. In these cows was detected milk production per lactation for 1000 kg higher than in cows that finished only 2 or 3 lactations. The lowest average yield per lactation was in cows that finished only two lactation. Furthermore, cows were evaluated according to the lactation curve. It was found that with increasing lactation persistence increases milk production but deteriorate the reproduction traits as a days open, insemination interval and insemination index. It was also found that with increasing lactation persistence decreases the longevity. Furthermore, we observed the level of milk productivity according to insemination index and found, that with increasing milk production increase insemination index.

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