[Continuing eco-pathological survey: 11. Development of pathological frequency in dairy cow stock as a function of the stage of lactation].

The study of disease distribution observed during lactation shows that three patterns of pathology may be described: diseases for which critical period is post-partum time: we observed during the first month of lactation 32.2% of cases of clinical mastitis, 43.9% of cases of metritis, 37.9% of digestive disorders, 59.6% of appetite troubles, 23.1% of treat lesions and 52.9% of udder edema. The monthly curve squares with asymptotic function. foot disorders for which the high milk yield production period is the more sensible time (three first month of lactation). The monthly curve, near a linear decreasing, squares with a quadratic or square-root function. ovarian pathology for which frequencies depends more acute attention from breeders or clinicians to reproductive disorders than objective observation of ovarian dysfunction.