Abstract: Bactrian camels in Haizi, Gansu, China are affected by an ailment characterized by pica, emaciation, dyskinesia, deprived appetites and anemia. Researchers found that concentrations of Cu in soil and forage from affected areas and unaffected areas were similar and within the normal ranges but the concentrations of S in soil and forage were significantly higher (p<0.01) in affected than in unaffected areas. Concentrations of Cu in blood, hair and liver from the affected camels were significantly lower (p<0.01) than those in unaffected camels. Fifty affected Bactrian camels grazed on affected pastures consumed an average of 136 mg of Cu/day for 60 days by a free-choice, salt-based trace mineral supplement. Average liver Cu concentration was and 37.9±5.5 μg g^-1 and at the end of the study. On the 62nd day, ten Bactrian camels and were removed from the affected pastures and allocated to one of two treatments for 80 days consisting of supplement providing 125 mg day^-1 of either Cu sulfate or Availa-Cu. Liver Cu increased over time in all camels regardless of treatment, however, camels supplemented with Availa-Cu have higher mean liver Cu contents than those receiving Cu sulfate (163.6±13.5 and 228.9±26.7 μg g^-1 for Cu sulfate and Availa-Cu, respectively) at the end of the study. Mean Cu content in the liver of Bactrian camels received Availa-Cu was significantly higher than that in supplemented camels with Cu sulfate. Thus, it is reasonable to conclude that ailments of Bactrian camels in the Haizi area are caused by a secondary Cu deficiency mainly due to high sulfur content in soil and forage.