Effect of Marginal Dietary Zinc on Blood Fractions of Rats

This study investigated the effects of marginal dietary zinc on blood fractions in rats. Two groups of rats were fed either a low zinc diet (6 ppm) or a zinc-adequate diet (30 ppm) for 8 weeks. The study found that rats on the low zinc diet had decreased food intake, failed to gain weight, and 29% showed hair loss and/or scaly paws. While RBC count, hemoglobin, and hematocrit increased over time in both groups, there were no significant differences in RBC zinc values between or within groups. The most notable difference occurred at week 2, with significant body weight differences and initial signs of hair loss in the low zinc group. However, the study did not find convincing evidence of changes in blood fractions due to marginal dietary zinc intake, despite other signs of zinc deficiency in the low zinc group.