Factors responsible for post parturient metritis in dairy cattle.

Factors associated with retained placenta and post parturient metritis in Israeli-Friesian dairy cattle are examined. The overall incidence rate, in a total of 2017 calvings on seven farms, was 16.1 per cent for retained placenta and 37.3 per cent for primary metritis. Risk factors associated with retained placenta include rising parity, short gestations, induction of parturition, multiple births, summer calvings, left displacement of the abomasum and ketosis. Risk factors associated with metritis include declining parity, long gestations, induction of parturition, stillbirth, multiple births, low milk yield before drying off, left displacement of the abomasum, ketosis and winter calvings. A proposed aetiology of metritis is presented and the various possible factors involved are discussed.