Effect of genetic and environmental factors on lifetime milk and fat production of Holstein-Friesian cows
1997
Markovic, M. (Biotehnicki institut, Podgorica (Yugoslavia))
The lifetime performance traits (milk and fat yield, milk per day in milking, milk yield per day of productive and per day of lifetime) of Holstein-Friesian cows were investigated. The obtained results showed that varying of these traits was significantly influenced by genotype, system of housing, birth year of cows, number of lactations and by sires. Estimates of heritabilities, obtained by using REML methodology, were very low for all traits and ranged from 0.11 to 0.17, except for the fat percentage (0.39). Genetic and phenotypic correlations between lifetime milk yield and milk yield per day in milking, per day of productive and total life of cows were very high.
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