Effect of high dietary copper on the ceca of chicks

Including 120 to 250 mg./kg. additional copper in practical broiler rations significantly affected the cecal appearance. The ceca were distended and the contents were darker in color and more pasty in consistency, compared to controls. Adding monensin sodium, gentian violet, or ferrous sulfate alone or in combination with copper to the ration did not significantly change the appearance of the ceca. Copper concentrations in the cecal contents reached levels above 5000 mg./kg., suggesting that the mechanism of action of copper in changing the appearance of the ceca may be related to an inhibition of normal fermentation that occurs in this part of the gastrointestinal tract. Sulfate, chloride and carbonate forms of copper all significantly changed cecal appearance, but the oxide did not, nor did a non-copper containing sulfate source. Macroscopic appearance of the gizzard lining and the proventriculus was also significantly changed by adding 240 mg./kg. copper to the diet, and liver weight and lipid content of liver dry matter were significantly increased.