Heterospermic insemination of cattle using three bulls of the same breed
Revell, S.G.
Veterinary Record 133(1): 20
1993
ISSN/ISBN: 0042-4900 PMID: 8362486 Document Number: 411754
Oestrus was synchronized in 12 groups of 16-34 cows (3 dairy, 9 beef suckler herds) in North Wales and Northern England using norgestomet (Crestar) ear implants. 48 and 72 h after removal of the implants cows were artificially inseminated, half with semen from 1 bull, half with mixed semen from 3 bulls of the same breed (Limousin or Charolais; 20 million sperm doses). Mean conception rate for cows receiving mixed semen was 59.2%, which was 2.1% higher (non-significant) than for cows inseminated with semen from a single bull.