Behavioral and physiological responses of dairy goats to isolation

Eight Nubian and eight Alpine dairy goat does were used in a crossover experimental design to determine the effect of 30 min of isolation on behavior and plasma concentrations of thyroxine (T4), triiodothyronine (T3), cortisol, norepinephrine (NOR), and epinephrine (EPI). Isolation was hypothesized to produce an emotional state analogous to fear. Focal animal behavior was recorded for the initial five min of isolation. Blood samples were obtained via jugular cannulae at 0 (immediately prior), 10, 20, 30 (during isolation), 40, 50 and 60 min (after return to their group). Response to isolation was characterized physiologically by increased plasma concentrations of NOR (p less than 0.01), but not T3, T4, cortisol or EPI, indicating a sympathetic discharge. Isolated goats also vocalized more frequently (p less than 0.01) and spent a greater amount of time sniffing, trotting and rearing (p less than 0.05). The Nubian does reacted more strongly (elevated NOR, trotting and rearing, p less than 0.01) to isolation than the Apline does.