These phenomena were apparently related to the induction of mastitic responses by rbIL-8, such as the extensive infiltration of PMNL and clot formation in mammary secretions, because one of the four cows given the high dose of rbIL-8 did not develop clinical mastitis or secrete elastase, LDP, or IL-8, and this was also true of the four cows given the low dose (10 μg/quarter/head) of rbIL-8. Here, CPQ is linked to mastitis.