Využití bazénového vzorku mléka jako ukazatele chovatelského prostředí dojnic holštýnského plemene skotu. =:The analysis of utilizing the bulk milk sample as a demonstration of the stable environment of the Holstein cows /

The subject of the dissertations thesis has been the analysis of utilizing the bulk milk sample as a indicator of the stable environment of cattle of the Holstein. The monitoring was carried out in the Czech Republic in the ŠPZ Žabčice in 55 weeks (between January 2013 and February 2014). Bulk milk samples can be taken as indicators of the quality of the stable environment. We have found out that the average temperature in the stable had a significant influence on the average morning milk yield, on the content of fat, solids non-fat, minerals, active and titration acidities, freezing point of milk (BMM), density, rennet coagulation time, chloride-lactose ratio. The average relative humidity (RH) in the stable conclusively proved the average morning milk yield, content of fat and minerals, active and titration acidity and rennet coagulation time. During the evaluation of the influence of the average THI in a stable on milk composition and milk properties was evaluated as a significant effect on the average morning milk yield, content of fat, minerals, the value of active acidity and titration acidity, freezing point of milk, rennet coagulation time, quality curd and the number of somatic cells counts. The statistically significant effect of the light intensity in the stable was influence on the average morning milk yield and on the value of the titration acidity. When monitoring the influence of the refrigeration value on the composition and properties of milk, we found out its conclusive influence on the average morning milk yield, value of titration acidity and BMM. We have found out that the air velocity in the stable had the conclusive influence on the content of magnesium in the milk. Parameters of stable environment were ranked in terms of their impact on the composition and properties of bulk tank milk samples (from the highest correlation to the lowest): average temperature, average THI, average RH, refrigeration value, light intensity and air velocity. Number of chewing movements can be considered as indicators of quality breeding environments