FACTORS INFLUENCING THE SOMATIC MILK-CELL-COUNT IN DAIRY-COWS - 1 - INFLUENCE OF BACTERIOLOGICAL FINDINGS, STAGE AND NUMBER OF LACTATION

When examining weekly the quarter milk samples of 200 cows bacteriolog ically and cytologically, more than 20% of the samples were bacteriolo gically positive. These positive quarters proved to have a 3-5 fold hi gher SCC than the negative ones. This difference could also be demonst rated in the comparison between bacteriologically positive and negativ e quarters of individual cows. But some cows even developed very high SCC without isolation of bacteria at any time. It could be proved agai n, that non-hemolytic staphylococci cause a moderate SCC rise and that the SCC increases in a statistically significant manner with the stag e and number of lactations. The seasonal SCC rise could mainly be attr ibuted to the high number of cows in late stages of lactation in some months of the year.