80 

 the supplemented treatments when compared to controls. It was 

 concluded that, at adequate levels of dietary Zn, 

 bioavailability of supplemental Zn source may be of less 

 importance than when added to low Zn diets or at higher 

 supplemental levels. 



Experiment 2 was conducted to compare supplemental ZnLys, 

 ZnMet, ZnS0 4 , and ZnO on Zn, Cu and MT concentrations in 

 various fluids and tissues of 40 wether lambs. Supplemental 

 Zn (3 60 mg/kg) was fed for 3 wks , withdrawn for 4 wks and then 

 resumed for another wk . Mineral (Zn and Cu) concentrations 

 were determined in serum, liver, pancreas, kidney, bone, bone 

 marrow, hoof, and leg muscle and only Zn was determined in 

 skin and cornea. Metallothionein content was determined in 

 liver, pancreas and kidney. By d 49 serum Zn had increased 

 less (P < .05) for controls than all but ZnMet, and by d 55 

 had increased more (P < .05) for ZnLys than all but ZnS0 4 . 

 There were no treatment effects in serum Cu content, but 

 overall Cu content fell slightly. The ZnLys treatment 

 produced the highest (P < .05) Zn accumulation in kidney, 

 liver and pancreas. Both ZnS0 4 and ZnMet treatments produced 

 higher (P < .05) liver Zn concentrations than the control 

 treatment. Mean Zn content of bone, bone marrow, cornea, 

 skin, hoof and muscle was not different (P > .05) among 

 treatments. The ZnLys treatment produced the highest (P < 

 .05) MT levels for liver, kidney, and pancreas. Mean muscle 

 Cu concentration was highest (P < .05) for controls (10 



