|
|
Effect of internal factors on milk production and quality
Šťásek, Jan ; Toušová, Renata (advisor) ; Jan, Jan (referee)
The aim of this thesis was to monitor and evaluate the impact of internal factors on the production and quality of milk in a herd of montbeliarde cattle. The hypothesis was that worse results of reproduction adversely affect milk production. Data collection took place on a farm Osičky agricultural company Agrodružstvo Lhota pod Libčany for the period from 1.1.2010 to 31.12.2015. The file was obtained 1 849 standard lactations completed in this period. The source of data for evaluation of milk production, milk quality and reproductive performance of cows were cards, program Farmsoft from Farmtec used to herd management and output data from the inspections carried out by the utility Chovservis Inc. residing in Hradec Kralove.
A statistically highly significant difference (P<0,01) between the first and all other amounts lactation in milk, fat and protein kg per lactation and fat in % and between 1st and 5th and more lactations in % protein. Was a positive effect of length of service period and the length of the intervening period the quantity of milk, fat and protein in kg per lactation at significance level P<0,001 and the negative influence of the length meantime to protein content in % (P<0,001). He was also found at least P<0,001 positive effect on lactation length produced kilograms of milk, fat and protein. Fat and protein also positively influenced the amount of milked milk (P<0,001). It was statistically insignificant effect on the incidence of mastitis production and milk quality (P>0,05), based on correlations may have an adverse effect on the percentage of fat and protein at a higher incidence of mastitis expected. The influence of the proportion of blood Montbeliarde breed was statistically proven only on the amount of milk and protein in kg per lactation, but still pure-bred animals came out the best in all of the indicators except for milk production fat percentage.
From comparison of the calving showed that his herd performance increases every year, the quality of milk as the fat content in % but conversely decreases. For the month of calving has been shown to influence the percentage of fat and protein at a significance level of P<0,001, the quantity of milked milk (P<0,01) and the amount of produced protein in kg per lactation (P<0,05).
The hypothesis that impaired reproduction results negatively affecting milk production has not been confirmed. It was found to influence reproduction indicators on production and quality of milk, but this influence in a positive direction. The negative effect was demonstrated only for the length of the interim influence on protein content in %.
Overall, the level of flock assessed as very good, but there are many indicators of production and reproduction that is necessary with respect to the potential of improving the breed.
|
guest ::
