1. Liver samples were taken from 95 mature zebu cattle and buffalo in Malaya for determinations of copper. A larger proportion were from Perak than from other States but whether the Perak samples were considered alone or with the remainder about 80% had liver copper values below 20 p.p.m.
2. Among Perak animals (all cattle) almost all those with low copper values were in moderate to poor condition but among the remainder about 50% of these with low copper values were in good condition.
3. In 12 Perak animals the numbers of parasites of the gastro-intestinal tract and of pancreatic and liver flukes were determined as well as the concentrations of liver copper. There were very few parasites other than pancreatic and liver flukes. Liver flukes may have caused low copper values in some animals but in general there was little evidence for a relationship between parasites and a low copper status. Anaemia did not accompany low liver copper values in these animals.