Mean plasma cortisol concentration in Bos taurus cows.

Cows were lactating (L, ──■──; n = 8) or non-lactating (NL, ‒ ‒ □ ‒ ‒; n = 10). Head restraint start time and duration are indicated by the black bar. The pooled SEM was 4.0. An effect of lactation (P = 0.02) was detected, however there was no interaction between lactational status and intra-nasal treatment (P = 0.55).