Acute effect of 9 -fluoroprednisolone acetate (9 FFA) on blood leukocytes and somatic cell content of milk

Lactating Holstein cows received 0 (saline), 5, or 10 mg 9α FFA immediately following morning milking. Thereafter blood samples were collected hourly until completion of the evening milking 10 hours later. Treatment with 9α FFA resulted in a linear increase in plasma glucose during post-treatment (P 0.10). Direct microscopic measurements of somatic cell content of fore, primary and residual milk revealed no significant (P > 0.10) effect of 9α FFA on number of total somatic cells, granulocytes, agranulocytes, or epithelial cells. These results suggest that corticoid-induced leukocytosis of blood is not reflected by increased somatic cell numbers in milk.