Adrenal Response to Adrenocorticotropin in Holstein Heifers Exposed to a Cool Environment

Abstract
Ten Holstein heifers acclimated to -2.7 or 19.1.degree. C were used to determine glucocorticoid concentrations in plasma following injection of ACTH (200 IU). Environmental treatments did not change glucocorticoids following ACTH. ACTH injection elevated mean glucocorticoids to 41.6 ng/ml plasma at 2.7.degree. C and 42.8 ng/ml at 19.1.degree. C. Adrenal response to ACTH in Holstein heifers was not altered by low environmental temperature.