RELATIONSHIP BETWEEN INDIVIDUAL COW UDDER HEALTH-STATUS IN EARLY LACTATION AND DAIRY-COW CHARACTERISTICS IN BRITTANY, FRANCE

Data from a 4-year ecopathological survey involving 47 dairy farms in Brittany (France) were used to determine the individual animal charact eristics associated with the udder health profiles of clinical and sub clinical mastitis, and the presence of minor or major pathogens in mil k during early lactation. Herd effect was taken into account and a wit hin-herd analysis using factorial correspondence analysis and a decomp osition of chi-square distance was performed. In primiparous cows, the main association observed was between milk production and intramammar y infections with major pathogens. The dirtiness score showed contradi ctory relationships with udder health profiles. The indoor/outdoor tra nsition period was unfavourable for udder health status; since the fre quency rate of subclinical and clinical mastitis increased during this period. In multiparous cows, intramammary infections by minor or majo r pathogens were closely associated with non-infectious udder diseases , but the main effect was due to parity. Old cows were generally affec ted by higher somatic cell counts than younger cows regardless of whet her the SCC were associated with clinical mastitis or not. (C) Inra/El sevier, Paris.