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

Jankowska M. 2002. DOUBLE INSEMINATION OF COWS DURING ONE OESTRUS, EJPAU 5(1), #02.
Available Online: http://www.ejpau.media.pl/volume5/issue1/animal/abs-02.html

ABSTRACT

Data on insemination and reinsemination were collected from 1 643 Black and White (BW) cows with varied share of Holstein–Friesian (HF) genes, which belonged to the active population managed in five large–scale production farms in the Kujawsko–Pomorskie Province, Poland. A total number of 351 repeated inseminations were recorded, which amounted to 7.71% of all inseminations. The rates of non–return to oestrus after reinseminations were by 2.05% better in relation to single inseminations, however, an economical analysis led to a conclusion that double insemination does not produce economical benefits and can only be recommended in specific cases, e.g. with prolonged oestrus. Highly significant effect on non–return rates after inseminating once or twice was demonstrated for the factors of HF genes share, farm, milk yield, age at first calving, subsequent calving, and season of insemination.

Key words: cattle, dairy cows, insemination, reinsemination.

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