[Diseases and culling of Swiss dairy cows. 2. Culling and relation between diseases and milk production parameters].

During three years (1982 to 1984) data were collected concerning diseases and reasons for culling in 612 dairy farms with Brown Swiss, Simmental and Black and White cattle. The frequency of culling increases in all three breeds with increasing age, from 20% at the first lactation up to 33% from the 4th lactation on. The main reasons for disposal are insufficient production, reproductive problems or udder diseases. After treatment for reproductive problems, mastitis or acetonemia, the risk for culling within the same lactation period is increased. Reproductive problems (no heat symptoms, repeat breeder, ovarian cysts) and acetonemia increase with increasing milk production in all three breeds. In cows with high 100-day-performance they are also more frequent. The occurrence of acute mastitis shows no general trend with increasing milk production or with high 100-day-performance. No systematic relationship is found between reproductive disorders or acute mastitis and persistency of milk production. On the other hand, acetonemia is somewhat more frequent in cows showing higher persistency.