Experimental zinc deficiency in guinea-pigs: biochemical changes

Abstract

1. Zinc deficiency was produced experimentally in guinea-pigs fed on a diet containing 1.25 mg Zn/kg diet over a period of 60 d. In addition, the response of the Zn-deficient (ZnD) animals to Zn supplementation was studied for 15 d.2. In the ZnD group a significant reduction was found in serum Zn and protein concentrations and in alkaline phosphatase (EC 3. 1. 3. 1; AP) activity from day 24 onwards.3. Paper electrophoretic studies on serum revealed a significant decrease in relative values, as well as absolute values, of albumin and γ-globulin and an increase in β-globulin.4. Albumin:globulin increased on day 24 but decreased significantly from day 48 onwards.5. The kidney and testis of the ZnD group showed a reduction in Zn and protein contents, and AP activity.6. Zn supplementation of the previously ZnD group resulted in marked although incomplete improvement in the biochemical indices studied.

Effect of Zinc Supplementation on the Status of Thyroid Hormones and Na, K, and Ca Levels in Blood Following Ethanol Feeding

“…Other studies have also demonstrated that zinc supplementation in the diet could improve thyroid function as indicated by the reduction in TSH values [31]. Reduced serum zinc concentrations upon ethanol feeding in the present study are in agreement with the observations of other workers [32,33]. These lowered serum zinc levels may be due to an increased ethanol-induced urinary zinc excretion.…”

Effect of Experimental Zinc Deficiency on Thyroid Gland in Guinea-Pigs

“…Serum Zn con centrations in the present study are in agree ment with the observations of other workers [9,11,12] who have also reported reduction in serum Zn concentrations in ZnD guineapigs. Growth retardation due to Zn deficiency in guinea-pigs as observed in the present study has also been reported in other species of animals [14], This might be due to impair ment of DNA synthesis since during Zn defi ciency the enzymes (thymidine kinase and DNA polymerase) and a hormone, somato medin C, required for DNA synthesis have been reported to be decreased [14,15], Sec ondly, hypothyroidism might have also con tributed to growth retardation [14], Lower values of serum T3 and T4 observed in ZnD guinea-pigs of the present study have also been found to be associated with Zn defi ciency in rats [2,3,5,16,17] and human beings [ 18].…”

“…However, in guinea-pigs, no pair feeding is required since Zn deficiency in guinea-pigs does not cause anorexia. In our previous experimental studies [9,10], we did not observe anorexia due to Zn deficiency in guinea-pigs. Similarly, other workers [11][12][13] also did not notice any significant effect of Zn deficiency on food intake in guinea-pigs and thus they did not use pair-feeding.…”