Out of 5970 calvings, 4.29% had an abnormal course (dystocia). The occurrence of stillbirths was 6.98% of all births and 4.15% of normal course births. Stillbirths occurred in 70.31% of dystocias. The highest frequency of stillbirths was in Blonde d´Aquitaine (8.59%) and the lowest in Gasconne (3.96%) cows. A narrow pelvis and an oversized foetus were the causes of more than 50% cases of dystocia. In Charolaise, an extremely high occurrence of oversized foetus, while in Blonde d´Aquitaine uterine inertia were found. A narrow pelvis was especially frequent as the cause of dystocia in the Aberdeen Angus and Limousine breeds. On analysis of stillbirths the most important effect was of the calving course with 24.47% impact on variability. Difficult calving increased the odds of stillbirth by 76 compared to normal calving. The heritability of stillbirth was estimated as 7.80%. It is recommended to restrict the use of sires with a higher incidence of dystocia or stillbirth in the offspring. As genetically determined variability is very low, other systematic measures are necessary to control stillbirth and dystocia. These are: supervision of the herd, obstetrical assistance, appropriate heifer rearing, mating cows at the proper live weight and proper nutrition during the pregnancy.
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