Effect of Salmonella gallinarum Infection on Zinc Metabolism in Chicks

The effect of Salmonella gallinarum infection in chicks on serum, liver, and kidney zinc concentrations was studied. Within 48 h after intraperitoneal administration of the organism, serum zinc declined to approximately one-half the control value. In one experiment, the serum zinc concentration remained low for the 12 days of the experiment, whereas in a second experiment, the concentration gradually increased after 6 days postinoculation but never returned to the control value. Feeding as much as 500 ppm supplemental zinc did not prevent the infection-induced decline in the serum zinc concentration. The infection resulted in a sequestering of zinc in the liver; the kidney remained relatively unresponsive in this system. Fractionation of liver homogenates by gel filtration column chromatography revealed that the zinc in the livers of the infected animals eluted in a volume characteristic of metallothionein, whereas that of control animals was associated with high molecular weight proteins. Increasing the zinc content of the serum by repeated subcutaneous injections of zinc had no effect on mortality from this infection. Restricting feed consumption of uninfected chicks to that of infected animals did mimic the influence of infection of serum zinc and hepatic metallothionein concentrations.