Results of dairy cows´ conception rate according to type of heat detection

The aim of this work was to elaborate literature review on the issue of cattle reproduction, factors influencing fertility and describe the various types of heat detection. The work also includes practical observations, which was based on comparing the results of its own conception of cows depending on the type of heat detection. The hypothesis was that the results of visual observation will have lower levels of reproduction than heat detection using measuring physical activity. The comparison was carried out within the company ZOD Roztoky Kruh, which is located in Roztoky u Jilemnice and enterprise Zetka Strážník, a.s. in Studenec u Horek. Information about the results of reproduction and performance were collecte in the two companies taken from their Analysis of herds registered in the stud book of Czech Fleckvieh and the Results of milk recording system during the period 2012 to 2015. Consequently, the results of reproduction were evaluated graphically for each business separately and then they were compared for both companies between themselves and within the whole population. As selected reproduction indicators for comparison, I selected the number of pregnant cows after all inseminations, insemination interval, service period, insemination index and length of the calving period. The comparison showed that the two companies is different in nearly all indicators of reproduction, except calving period, the length of which was in both companies almost the same, on average from 394 to 396 days. In ZOD Enterprise Roztoky Kruh faced with increasing length of calving period, which varies in length averaging about 99.9 days, which is considered inconvenient. In contrast, the length of insemination interval was shorted by an average of 8.5 days from the start of monitoring. The number of pregnant cows after insemination was on average around 52.6%, which is 4.7% less than in the enterprise Zetka Strážník, a.s., where it achieved 57.3%. The index of insemination for cows was an average of 1.75. The enterprise Zetka Strážník had an average length of calving period 94.9 days. Insemination interval was prolonged by an average of 5.6 since 2012. The index of insemination for cows had an average value 1.55. This indicator is not influenced by the type of heat detection. The hypothesis was confirmed even though the difference was not too great. Enterprise, which used measurements of physical activity to detect estrus, had better results in terms of reproduction. We can see that heat detection using visual observation is not as effective as using the detectors that detect physical activity in a stable all day