Experimental zinc deficiency in guinea-pigs: clinical signs and some haematological studies.

Thirty-three male, weanling guinea-pigs were divided into two groups. One group was fed on a zinc-deficient (ZnD) diet (1.25 mg Zn/kg diet) for 45 d and then divided into two subgroups: subgroup 1 continued on diet ZnD while subgroup 2 was fed on a Zn-repleted diet (100 mg Zn/kg diet) for 15 d. The second group was fed on a Zn-adequate diet (50 mg Zn/kg diet) for 60 d. Zn deficiency could be produced within 21 d as evidenced by clinical signs and reduction in serum Zn concentration. Clinical signs exhibited were listlessness, scabby lesions on skin near the foot pads, mild alopecia and a reduction in body-weight gain. No effect was observed on food intake. Significant decreases in packed cell volume and total leucocyte count from 48 d onwards accompanied by absolute lymphocytopenia and relative neutrophilia were observed. Supplementation of Zn in the Zn-repleted group resulted in marked, through incomplete, improvement with regard to serum Zn concentration, clinical signs and haematological changes.