Effect of copper on growth and serum constituents of immunized and non-immunized rabbits infected with Trypanosoma brucei.

Seventy-two five-week-old New Zealand White rabbits were divided into three groups and fed a basal diet containing 0, 125 or 250 ppm supplemental Cu for 4 weeks before each Cu-group was further subdivided into three lots of 8 rabbits each. One subgroup was immunized with Trypanosoma brucei before being infected with the same parasite, another subgroup was infected without immunization while the third subgroup was neither immunized nor infected. Parasitemia slightly depressed growth and efficiency of feed utilization while supplemental Cu at 125 and 250 ppm improved both parameters in rabbits. Immunization conferred slight protection on body weight losses by the infected rabbits while supplemental Cu at 250 ppm alone or in combination with immunization completely obliterated the effects of infection on growth performance. Infection depressed haematocrit, haemoglobin, and serum glucose, while the alkaline phosphatase activity was increased. Supplemental Cu significantly increased both haemoglobin and serum glucose levels. Supplemental Cu reversed the effects of parasite infection on blood constituents. The study indicates that Cu may not only promote growth but will also suppress the effects of parasitemia on performance and serum profile of rabbits infected with trypanosomes.