Effects of treadmill exercise on sweating in three breeds of goats

To compare the sweating responses of three breeds of goats to exercise at 30 degrees C.

Factorial experiment with two goats of each of three breeds exercised for 60 min at 3 km/h and 30 degrees C on 6 days.

Two mature females of the Anglo-Nubian, Saanen and Toggenburg breeds were used. Rectal temperature, respiration rate and sweating rate at three sites were recorded every 20 min during six replicates of exercise at 48 h intervals on a treadmill.

Respiration rate varied with time and breed (P < 0.01) and increased from 20 +/- 2 breaths/min to 135, 195 and 260/min after 60 min exercise in Anglo-Nubian, Saanen and Tottenburg goats, respectively. Bread differences in rectal temperature were small but significant (P < 0.001), and mean values increased from 38.9 degrees C before exercise to 39.7 degrees C after 1 h exercise. The breed x sites interaction for sweating was significant (P < 0.01). On the rump breed differences in sweating rate were not significant. On the loin, Toggenburg goats started to sweat most rapidly and reached maximal values of 80.2 +/- 10.6 g/m2/h after 20 min and then decreased to 70.0 +/- 4.3 g/m2/h at 60 min. Sweating rate on the ear was highest in Toggenburg goats, followed by those of Saanen and Anglo-Nubian goats (P < 0.05), but the differences were small (7 g/m2/h); peak values of 67.3 to 76.1 g/m2/h were recorded after 20 min.

Respiration and sweating rates increased significantly during exercise in all three breeds of goats, but breed differences were marked only for respiration rate. The goats sweated more on the rump than on the loin on ear, with peak values after 40 min of exercise.