43 

 and pancreas of the ZnLys treated animals. The other organic 

 source (ZnMet) was not different than ZnS0 4 . There is a 

 possibility that if the ZnLys treatment had been omitted there 

 would be differences between the ZnMet and ZnS0 4 groups 

 compared to the ZnO and control groups, due to the high values 

 of the ZnLys group particularly for liver and kidney Zn and MT 

 levels, which might imply different variances for the 

 different means. No differences were observed in the bone Zn 

 deposition for the various treatments. This is unlike the 

 work of Wedekind and Baker (1990) which showed increased bone 

 Zn deposition in chicks fed ZnMet relative to ZnO and ZnS0 4 . 

 Wedekind et al . (1992) also suggested that bone Zn levels 

 increased when ZnMet was used compared to ZnS0 4 or ZnO in 

 chicks, however, they did not use fat-free bone in their 

 study. Results reported herein (no differences) also agree 

 with those of Medeiros et al . (1989) who found that ZnMet did 

 not influence muscle (longissimus or biceps femoris) Zn 

 content . 



Metallothionein determination was valuable in assessing 

 the differences among Zn sources. Mean liver, kidney and 

 pancreas MT levels from the ZnLys treatment ranged anywhere 

 from about 3 to 40 times greater than the other treatments. 

 The closest values were those for ZnMet and ZnS0 4 and the 

 lowest values were usually those of the negative control group 

 which was expected. These MT determinations confirm the poor 

 biological value of ZnO, with tissue concentrations associated 



