Effects of stage of lactation, production, parityand 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). Composite milk samples from all lactating does were cultured for mastitis pathogens every 6 months. Dairy Herd Improvement Association records were combined with culture results. Goats' SCC increased with intramammary infection (IMI). Increasing stage of lactation was also associated with increased SCC in goats with or without diagnosis of IMI. Lower mature equivalent milk production and increased parity were also associated with higher cell counts. Goats lactating during October, December and January (months with highest mean DIM) had increased SCC. Non-infected goats frequently had SCC greater than 1 000 000 ml−1. Much (approximately 90%) of the difference in goats' SCC was not due to IMI. Of the variation in SCC among does, 77% was unexplained. Alternative tests for goat milk quality would be beneficial for the industry.
Wilson DJ, Stewart KN, Sears PM: Effects of stage of lactation, production, parity and season on somatic cell counts in infected and uninfected dairy goats. Sm Rum Res 16:165-169, 1995.