Nauka Przyroda Technologie

The aim of the study was to determine daily milk yields from individual udder quarters in cows and their susceptibility to mastitis established on the basis of electric conductivity of milk. Analyses were conducted in the period from 1.09.2010 to 31.12.2011 in a herd (137 head) of black-and-white Holstein-Friesian cows. Data for analyses were obtained from the DelPro programme operating milking robots by DeLaval. The analyses showed that hind quarters are characterised by greater daily milk yields in comparison to fore quarters. In terms of hind quarters more advantageous daily milk yields were recorded for left quarters. When analysing electric conductivity of milk collected from individual udder quarters the most advantageous value of this parameter was found in milk coming from left hind quarters. In terms of peak and mean milk flow during milking the worst results were found for left fore quarters. Statistical analysis showed a significant effect of lactation rank and its phase on investigated traits of individual udder quarters. When analysing health status of the mammary glands based on electric conductivity of milk collected from individual udder quarters it was found that fore mammary glands were more susceptible to inflammation in comparison to hind glands. The breeding work should seek to align the lists in terms of conformation and production traits.