THE EFFECT OF MILK PERFORMANCE OF DAIRY-COWS ON THE GROWTH, EARLY MATURITY AND MILK-YIELD OF THEIR DAUGHTERS

An analysis of the effect of dam's maximum lactation and dam's lactation before the birth, or lactation after the birth of her daughter, revealed that in none of the cases were the statistically significant differences found out in the growth rate and early maturity of breeding cows of the Improved Bohemian Pied breed. As to milk performance, a positive trend was observed in all three evaluated lactations although there were statistically significant differences in milk yield (11.9%) and in milk fat content (11.42%); they were revealed by an evaluation of lactation after parturition. The data were collected at the milk yield of daughters - first-calvers reaching 4200 kg. Ensuing from the overall evaluation, lactation after parturition seems to be the most suitable characteristic for an estimation of the mother-daughter relationship; but there is one disadvantage because this value is known only at the daughter's age of about one year.