26 

 |ll of Cd solution (2 |ig Cd and .5 |iCi 109 Cd per ml of 10 mM 

 Tris-HCl buffer, pH 7.4) were added to a 200 [ll aliquot of the 

 supernatant and the mixture was incubated (10 min; room 

 temperature) . Finally, 100 |J.l of 2% hemoglobin were added. 

 The sample was then heated (100°C; 2 min) and centrifuged 



(10,000 x g; 5 min) . This step was then repeated and 100 (il 

 of the supernatant and standard solutions were placed in a 

 Gamma Spectrometer Model 4000 (Beckman Instruments, Inc.) to 

 measure 10y Cd levels. These levels were then used to assess MT 

 concentrations . 



The experiment was designed as a 4 x 4 factorial in a 

 completely randomized experiment. There were four Zn 

 treatments, three sources of Zn and one negative control, and 

 four levels of vitamin E. All data were analyzed using SAS 



(SAS, 1988) . Repeated measures ANOVA was performed using the 

 general linear model (GLM) procedure on changes (increase or 

 decrease from d 1) in Zn and Cu concentrations in serum, and 

 on changes in Zn concentrations in erythrocytes. Tissue Zn 

 and Cu data were analyzed using GLM. In case of significance 



(P < .05) in serum or tissue data, Waller-Duncan's K-ratio T 

 test was used for multiple comparisons. 



Results 



Since no zinc x vitamin E interaction was found the 

 statistical evaluation was based on main effects. The vitamin 

 E data were discussed by Njeru et al . (1993) . Weight gains 



