The Effects of Nor-adrenalin Administration on Blood Characteristics in Different Fattening Conditions of Holstein Steers

The effects of nor-adrenalin (NA) administration at normal feeding time and after fasting for 48 hours on hematocrit value (Ht value), concentration of plasma glucose, free fatty acid (FFA), insulin and creatine phosphokinase (CPK) were studied for high finishing weight lot (H lot: average body weight was 675kg for three heads) and low finishing weight lot (L lot: average body weight was 611kg for three heads) of Holstein steers. Ht value increased extremely 5min after the administration of NA in both lots. There was no significant difference between the H and L lot in basal glucose level before NA administration. 5min after NA administration, the glucose level increased rapidly in both lots, especially in H lot at normal feeding, but after fasting for 48 hours, this effect was not remarkable compared with that of the normal feeding time. FFA concentration was observed to have an extremely high elevation at fasting time; furthermore NA administration made this elevation higher. The basal level of plasma insulin and its degree of elevation after NA administration were significantly higher in H lot than in L lot. Fasting for 48 hours caused a decrease of insulin level at the basal level and after NA administration, and this tendency was more remarkable in L lot. Plasma CPK value was not influenced by fattening conditions and NA administration.