Studies on copper metabolism in the cotton rat Sigmondon hispidus texianus

Graduation date: 1965The effects of different levels of copper in the diet on growth\ud rates, blood and liver copper concentrations, hemoglobin levels,\ud and cytochrome c oxidase activities were determined in the cotton\ud rat. The response of the cotton rat to different levels of copper was\ud analagous to that of the common laboratory rat. The blood and liver\ud copper patterns followed a course similar to that of most species\ud fed different levels of copper. Six and one half parts per million\ud copper were assumed to approximate "normal" copper levels, while\ud the 1.5 ppm level was definitely subnormal. The 50 ppm copper\ud level appeared to approach the toxic level, even though some copper\ud dependent functions were stimulated in this latter group. Copper in\ud concentrations of over 1.5 ppm was needed for better growth, hemoglobin\ud formation, and normal pigmentation. When the cotton rat\ud was given excessive amounts of copper, these functions, with the\ud exception of hair pigmentation, were depressed slightly. The\ud cytochrome oxidase activity in cotton rats was not demonstrated to\ud be significantly influenced by different levels of copper in the diet