Effect of dietary zinc deficiency on hematological and biochemical parameters and concentrations of zinc, copper, and iron in growing rats

Zinc has a wide spectrum of biological activities and its deficiency has be en related to various dysfunctions and alterations of normal cell metabolis m. The effects of adequate Zn level (38 mg/kg diet, control) and two low le vels that create Zn deficiencies (19 mg/kg diet, 1/2 of control and 3.8 mg/ kg diet, 1/10 of control) were investigated in growing male and female rats for 10 weeks. This allowed for evaluation of the effects these Zn levels m ay have on body weight gain, specific organ weights, blood parameters, and serum concentrations of Zn, Cu and Fe. Rats fed Zn-deficient diets gained l ess (P < 0.05) than the control groups. There was increase (P < 0.05) in li ver and spleen weights, and a decrease (P < 0.05) in testes weight. However , brain, kidney, heart, and lung weights were not affected (P < 0.05). Hema tological parameters that were decreased (P < 0.05) by Zn deficiency includ ed hemoglobin (Hb), total erythrocyte count (TEC) and packed cell volume (P CV) with the magnitude being dose-dependent. Serum concentrations of total protein, globulin, glucose, and high density lipoprotein (HDL) also decreas ed (P < 0.05) in a dose-dependent manner. Zn deficiency increased (P < 0.05 ) total leukocyte count (TLC) and concentrations of serum albumin, total li pids, cholesterol, triglycerides and low density lipoprotein (LDL) in a dos e-dependent manner. Serum concentrations of urea and creatinine were, howev er, not affected (P < 0.05) by zinc deficiency. Zn-deficient rats had lower serum concentrations of Zn, Cu and Fe. These results showed that Zn defici ency has negative effects on growth rate, specific organ weights, hematolog ical parameters, and serum levels of Zn, Cu and Fe, especially in rats fed the lowest Zn level. (C) 2001 Elsevier Science Ireland Ltd. All rights rese rved.