EFFECTS OF STAGE OF LACTATION, PRODUCTION, PARITY AND SEASON ON SOMATIC-CELL COUNTS IN INFECTED AND UNINFECTED DAIRY GOATS

A commercial, dairy goat farm with 380 Alpine milking does maintained monthly records of milk production and somatic cell counts (SCC). Comp osite milk samples from all lactating does were cultured for mastitis pathogens every 6 months. Dairy Herd Improvement Association records w ere combined with culture results. Goats' SCC increased with intramamm ary infection (IMI). Increasing stage of lactation was also associated with increased SCC in goats with or without diagnosis of IMI. Lower m ature equivalent milk production and increased parity were also associ ated with higher cell counts. Goats lactating during October, December and January (months with highest mean DIM) had increased SCC. Non-inf ected goats frequently had SCC greater than 1 000 000 ml(-1). Much (ap proximately 90%) of the difference in goats' SCC was not due to IMI. O f the variation in SCC among does, 77% was unexplained. Alternative te sts for goat milk quality would be beneficial for the industry.