The Development Changes and Correlations of Some Blood Hormone Levels and Immune Indexes during the Postnatal Period in Neonatal Calves

Abstract

The developmental changes and correlations of some hormone levels and immune parameters in six spontaneously delivered Holstein calves with a birth weight of 40-50 kg were studied for a postnatal period of 1-15 days after birth. The mean levels of insulin (I), glucagon (Gc), cortisol (C) and growth hormone (GH) before feeding on day 1 were 9.68 +/- 3.27 muu/ml, 685.39 +/- 95.42 pg/ml, 14.27 +/- 5.58 micrograms/dl and 0.85 +/- 0.10 ng/ml respectively. I and GH increased on day 2 and then decreased to a steady level. Gc and C fell fluctuantly within week 1 and remained at a stable level after then. WBC, neutrophil percentage, B-lymphocyte percentage, albumin percentage decreased with day of age in 1st week and lymphocyte percentage, T-lymphocyte percentage, T-G (total globulin) percentage and gamma-G percentage increased with day of age in 1st week and then reached a steady level. The correlations between some hormone levels and immune parameters indicated that C and Gc have significantly negative correlations with gamma-G (%), T-G (%) and T-lymphocyte (%) respectively. WBC is positively correlated to C and Gc significantly. The correlations of I and GH with some immune parameters have no significance.