Fertility and fertility problems in some beef herds in Sweden
Einarsson, S.; Olsson, B.; Bane, A.; Gustafsson, B.
Nordisk Veterinaermedicin 27(9): 411-428
1975
ISSN/ISBN: 0029-1579 PMID: 1178439 Document Number: 92999
Data on 703 Hereford, Charolais, Aberdeen-Angus (AA), Limousin and crossbred cows and heifers in 31 herds in central and southern Sweden were analysed. In the 5 groups, the number of calves surviving >24 h after parturition, as a percentage of females mated, averaged 76.4, 83.2, 90.7, 61.5 and 90.2 resp. Most calvings occurred in Feb.-May (74.7%); only 6.1% occurred in Sep.-Dec. Length of service period averaged 80.3, 92.3, 83.4 and 85.6 days resp. for Hereford, Charolais, AA and crossbred cows, and the frequency of twinning was 0.9, 6.0, 3.7 and 0.6%. The percentage of calf mortality within 24 h of parturition was 7.2, 13.4, 7.8, 0 and 5.2 resp. for Hereford, Charolais, AA, Limousin and crossbred females , and the percentage of difficult parturitions was 5.5, 10.8, 3.7, 25.0 and 5.8. Of cows calving in Jan.-Mar., Apr.-June, July-Sep. and Oct.-Dec., 93.9, 84.6, 81.4 and 95.8% resp. conceived during the next mating period. The calving percentage for females mated with Hereford, Charolais and AA bulls of lower than average fertility averaged 62.9, 72.4 and 33.3 resp. v 90.3, 95.4 and 91.6 for females mated with bulls of higher than average fertility. Approximately one third of bulls serving at least 10 females achieved calving rates of <80%. Most of these bulls were aged 12-15 mth.