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Sledování vnitřních vlivů na produkci a kvalitu mléka / Monitoring internal factors on milk production and quality

The aim of this thesis was to evaluate the influence of internal influences on the production and milk quality on selected farm. Data for preparation of this thesis were obtained on a farm in Skalica in Frydek-Mistek belonging to the joint-stock company Beskyd Agro. Data used in this thesis were evaluated for two years (1.10.2013-30.9.2014, 1.10.2014-30.9.2015). Data were analyzed and statistically processed using Microsoft Excel software. Evaluation of milk production and reproductive performance were based on the results obtained from regular inspections. For milk yield parameters were evaluated milk yield (kg) Fat (%, kg) Protein (%, kg) of milk somatic cell count (SB) depending upon reproduction and lactation. Evaluated herd were divided into 2 groups: I. lactation, II. lactation and the next lactation. Hypothesis: Worsening indicators of reproduction have negative impact on the level of milk production and its components.
The final evaluation of the data were used, comprising 280 cows of Holstein cattle, which were included in monitoring performance period. The results show that the average length of the interim period was around 416 days in average.Milk yield was 10,062 kg of milk with fat contents of 4.21%, 3.37% proportion of protein and somatic cell count 477.75 thousand / ml. The difference in milk yield of heifers at first (9 326.38 kg) and second lactation (9 901.47 kg) reached 575.09 kg. Maximum milk production was achieved on 4th lactation, when milk yield reached 10 432.16 kg per lactation.
Positive effect was demonstrated between the % fat content and protein content in%. With the increase in the% fat content, and increased protein content in%. The highest value of the average amount of fat has been statistically proven at 5th lactation and values of 4.18%. For proteins the highest number was reached during the lactation no. 6 with values of 3.40%.
The best values were obtained in lactation number 4., where the rate reached the following parameters:
milk yield per lactation 10,432, 16 kg
daily milk yield: 34.20 kg
fat: 4.08%
protein: 3.35%.
It was determined that the amount of milk yield per lactation in kg was positively affected by the value of the daily milk yield in kg, with the value (r = 1st) verified at a significance level (P <0.001). Increased milk yield per lactation kg should result in an increase daily milk yield. The negative impact was demonstrated in representating % fat content of milk (r = -0.653) and protein (r = -0.442) at the level of significance (P <0.001). Increased milk yield per lactation in kg was negatively effected and reduced the component of fat and protein. Milk yield per lactation had a positive effect on service period. Positive effect on milk yield heifers was demonstrated in service period and with a positive value (r = 0.327) with evidential significance level (P <0.05). Effect of milk yield per lactation, age at first calving was not demonstrated.
Effect of daily milk yield in kg of milk, had a negative effect on the proportion of components in % fat (r = -0.653) and protein (r = -0.442). Conclusive came to the level of significance (P <0.001). Increase in daily milk yield will reduce the content of components of protein and fat milk. The positive impact of the daily milk yield was demonstrated in connection with the service period (r = 0.247) at a level of significance (P <0.05). Increasing daily milk yield, this will extend the service period.
From the resulting data, negative effect on lactation representation% protein content (r = -0.288) and fat (r = -0.052) with evidential significance level (P <0.001) was determined . Effect of lactation on milk yield per lactation, daily milk yield, calving interval and service period has been shown.
Daily milk yield in kg of milk is affected by the amount of milk yield per lactation in kg (r = 1). Conclusive came to the level of significance (P <0.001). Increased milk yield per lactation is proportional to increase of daily milk yield. Milk yield per lactation negatively affected% of fat content (r = -0.187) and% representation of protein (r = -0, 208). Conclusive came to the level of significance (P <0.05). Increasing milk yield per lactation kg reduces% fat and protein. The relationship between milk yield per lactation in kg, service period, and interim periods has not been demonstrated.
Effect of daily milk yield in kg, had a negative effect on the% fat content (r = -0, 187) and protein (r = -0.208) with evidential significance level (P <0.05). Reduced% protein content and milk fat is a result of increased daily milk yield in kg. Effect of daily milk yield on service period and the interim has not been demonstrated.
Fat content in% and the protein in% (r = 0.603) were demonstrated at a level of significance (P <0.001). Increased if the% fat content, increased the% protein content.
The positive effect was demonstrated between service period and interim periods (r = 0.266) with evidential significance level (P <0.001). The longer the period of service increases the length meantime.
It was confirmed that with increasing lactation milk yield as per lactation, daily milk yield and milk components content.

Identiferoai:union.ndltd.org:nusl.cz/oai:invenio.nusl.cz:256932
Date January 2016
CreatorsKrálová, Alena
ContributorsToušová, Renata, Jan, Jan
PublisherČeská zemědělská univerzita v Praze
Source SetsCzech ETDs
LanguageCzech
Detected LanguageEnglish
Typeinfo:eu-repo/semantics/masterThesis
Rightsinfo:eu-repo/semantics/restrictedAccess

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