Electronic Journal of Polish Agricultural Universities (EJPAU) founded by all Polish Agriculture Universities presents original papers and review articles relevant to all aspects of agricultural sciences. It is target for persons working both in science and industry,regulatory agencies or teaching in agricultural sector. Covered by IFIS Publishing (Food Science and Technology Abstracts), ELSEVIER Science - Food Science and Technology Program, CAS USA (Chemical Abstracts), CABI Publishing UK and ALPSP (Association of Learned and Professional Society Publisher - full membership). Presented in the Master List of Thomson ISI.

Copyright © Wydawnictwo Akademii Rolniczej we Wroclawiu, ISSN 1505-0297

Kuczaj M. 2002. MILK PERFORMANCE ANALYSIS OF DAIRY COWS OF DIFFERENT COLOURS SIRED BY HOLSTEIN–FRIESIAN RED–FACTOR BULLS, EJPAU 5(1), #05.
Available Online: http://www.ejpau.media.pl/volume5/issue1/animal/abs-05.html

ABSTRACT

The analysis was carried out on 67 primiparous cows of different colour sired by black–white red–factor (RF) bulls, kept in a modern dairy farm in south–west Poland. The aim of this study was to confirm or reject the hypothesis that the daughters with different colours obtained from red–white mothers and black–white RF bulls may also differ in their milk yield during the first 305–day lactation corrected on age and calving season. The cows with different colour were statistically similar with regard to the investigated milk performance traits. Average corrected yield of RF bulls’ daughters with black–white or red–white colour was respectively 10 300 and 10 112 kg of milk with 4.31 and 4.32% of fat, and 3.08 and 3.13% of protein. The observed relative differences in the range of the investigated milk traits of cows with different colour were not higher than 2%, except for the FPD index. The greatest relative difference between cows with different genotype (below 75.0 and above 75.1

Key words: colour of cows and bulls, red factor, genotype, milk yield, milk composition.

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