RESPONSES OF YOUNG CALVES, ON 2 LEVELS OF FEEDING, TO TRANSPORTATION

The effect of transportation on energy metabolism in young calves was assessed at two feeding levels by indirect calorimetry during 5.5-day experimental period. Twenty-six Holstein-Friesian male calves were ass igned in a 2 X 2 factorial arrangement of treatments. Calves were fed below or near the maintenance requirements (270 or 420 kJ metabolizabl e energy per kg M(0.75) per day). At 5 days of age, 13 calves were tra nsported. The applied transportation procedure was aimed to mimic comm on transport of young calves. The other 13 calves were controls. Metab olizability of dietary energy was low (0.808), but similar for control and transported calves. Despite the similar salivary cortisol concent rations after transportation, heat production was higher by 23 kJ/kg M (0.75) per day in transported than in control calves. Calves were not in a steady-state regarding their energy metabolism. Heat production d ecreased with time. Both transportation and feeding level influenced t he decline in heat production with time. Both transportation and feedi ng level influenced the decline in heat production with time. Only dur ing the first 3 days after transportation was heat production enhanced , suggesting a relatively short-term effect of transportation in young calves. The impact of transportation on heat production and time rela ted alterations in heat production were not related to the calf's acti vity.