Les indicateurs de reproduction en élevage allaitant

Résumé

Seasonal calving system, the most common in beef cow-calf herds, is characterized by a limited breeding period to 3 or 4 cycles of 21 days (63 or 84 days) which is the same every year. The collection of reproduction monitoring data in seasonal calving system is made possible by the precise dating of the gestation by ultrasound examination. Different key performances indicators can be calculated from data and reproduction patterns indicating the pregnancy distribution per cycle of 21 days after the beginning of the mating period as well as the rate of non-pregnant cows can be represented. The pattern is a first step of analysis of reproductive performance. If degraded performances appeared during a breeding season, the type of pattern observed makes it possible to identify directly the possible primary cause(s) of this degraded fertility. The indicators in a year-round calving system as well as the indicators of peripartum disorders are also presented.