반추가축영향 : Holstein 수소와 거세우 및 Zeranol 투여 거세우의 성장 단계별 혈액상과 혈청 대사물질 및 호르몬 농도의 변화 = Ruminant Nutrition : Changes in Hematological Values and Concentrations of Serum Metabolites and Hormones During the Growth of Holstein Bulls , Steers and Steers with Zeranol Injection

다국어 초록 (Multilingual Abstract)

This experiment was conducted to investigate changes in hematological values and concentrations of serum metabolites and hormones during the growth of Holstein bulls, steers and steers with Zeranol injection. Animals were assigned into 3 groups, bull group (n=8), steer group (n=8) and zeranol group (n=8, injected with zeranol from 80㎏ to 450㎏ BW). Sixteen Halstein steers in steer group and Zeranol group were castrated at 2 month after birth and zeranol group was injected hypodermically with 36㎎/head of zeranol on the tail side at every 90 day. RBC, Hb, HCT values of zeranol group at the final stage of 650㎏ were significantly decreased and MCHC value was increased compared with steer group (P$lt;.OS), but WBC, MCV and MCH values remained same. Serum glucose concentrations of animals at 300㎏ BW were higher compared with those at different growing stages. Although all chemical values in serum at 500㎏ were not different between the treatment groups, SUN, albumin, cholesterol, triglyceride and calcium concentrations of zeranol group at the final stage (650㎏) were higher than those of other groups. Serum IGF-I concentration at the start of the experiment was not different among the treatments ranging from 5.24 to 8.29ng/㎖ and started to increase afterhood until animals reached 300㎏ of body weight. At 300㎏ BW, serum IGF-1 concentration of bull group was higher than that of steer group (350.2 vs 266.2ng/㎖, P$lt;.05). At 500㎏ BW, IGF-I concentrations of bull group and zeranol group were 525.6 and 504.6ng/㎖ respectively which are higher (P$lt;.05) than that of steer group (398.7ng/㎖). Similarly, serum insulin concentration was not different between treatments until animals reached 300㎏ BW ranging from 5.65 to 7.81ng/㎖. However, at 500㎏ BW bull group showed significantly lower (17.35ng/㎖) insulin concentration than that (24.76ng/㎖) of steer group (P$lt;.05).