Estimation of genetic parameters in the dairy cattle population of Saxonia

Population-genetic parameters of the dairy cattle population of Saxonia hav e been examined. The estimated heritabilities for milk quantity range betwe en 0.35 and 0.42, for fat content between 0.48 and 0.55 and for protein con tent between 0.52 and 0.57. Higher heritabilities were found for I st than for subsequent lactations. The genetic correlations between milk quantity a nd the fat and protein contents were significantly negative for all lactati ons, likewise between protein content and the protein quantity. The correla tion between fat content and fat quantity has been slightly positive (r(g) = 0.08), The analysis of genetic trends revealed a substantial increase in quantity traits, whereas a negative trend has been observed for the milk co ntent merits.